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Deebel NA, Bradshaw AW, Sadri-Ardekani H. Infertility considerations in klinefelter syndrome: From origin to management. Best Pract Res Clin Endocrinol Metab 2020; 34:101480. [PMID: 33358481 DOI: 10.1016/j.beem.2020.101480] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Klinefelter syndrome (KS) is defined as the presence of one or more extra "X" chromosome in a male patient. It affects approximately 1 in 600 newborn males and the most common chromosomal abnormality, leading to male hypogonadism and infertility. There is a lack of data supporting best practices for KS patients' care. In this paper we review controversial issues in KS research ranging from mechanisms of variation in KS phenotype to abnormalities resulting in reduced sperm production to successful sperm retrieval disparities after testicular sperm extraction (TESE). Translation to live birth and offspring health is also examined. Finally, medical therapies used to optimize the hormonal status and chances of fertility in KS patients are reviewed. We will also discuss the experimental spermatogonial stem cell (SSC) treatments, which are considered the future for TESE negative patients.
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Affiliation(s)
- Nicholas A Deebel
- Department of Urology, Wake Forest University School of Medicine, Winston-Salem, NC, USA; Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Aaron W Bradshaw
- Department of Urology, Wake Forest University School of Medicine, Winston-Salem, NC, USA; Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Hooman Sadri-Ardekani
- Department of Urology, Wake Forest University School of Medicine, Winston-Salem, NC, USA; Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA.
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2
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Huo P, Luo Q, Li J, Jiao B, Rong L, Zhang J, Wu X. High accuracy of quantitative fluorescence polymerase chain reaction combined with non-invasive pre-natal testing for mid-pregnancy diagnosis of common fetal aneuploidies: A single-center experience in China. Exp Ther Med 2019; 18:711-721. [PMID: 31281451 DOI: 10.3892/etm.2019.7625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 03/12/2019] [Indexed: 10/26/2022] Open
Abstract
Quantitative fluorescence polymerase chain reaction (QF-PCR) may be used as a mid-pregnancy test to confirm the diagnosis of common fetal aneuploidies, but its use is controversial. The present study aimed to determine the value of QF-PCR for diagnostic confirmation of karyotyping and the impact of parental origin and meiosis stage on the detected aneuploidy. The present prospective cohort study included pregnant women (age, 21-45 years; gestational age, 17-25 weeks) who consulted between May 2015 and December 2016. Women were screened and only consecutive high-risk individuals were included (n=428). QF-PCR analysis of amniocytes was performed. Karyotype analysis was considered the gold standard. Parental karyotyping was performed if the embryo exhibited any aneuploidy. GeneMapper 3.2 was used for data analysis. There were no false-negative or false-positive QF-PCR results, with 100% concordance with the karyotype. The aneuploidy distribution (n=105) was 68.6% for trisomy 21, 19.0% for trisomy 18, 7.6% for sex chromosome aneuploidy, 3.8% for trisomy 13 and 1.0% for 48,XXX,+18. Regarding trisomy 21, most cases (86.1%) were of maternal origin, 8.3% paternal and 6.5% undefined. Trisomy 18 was 88.2% maternal and 11.8% paternal. Maternal meiosis stage errors in trisomy 21 mainly occurred in meiosis I, while the origin of trisomy 18 exhibited similar proportions between meiosis I and II. The combination of non-invasive pre-natal testing and QF-PCR may become a rapid and effective method for fetal aneuploidy detection. QF-PCR may provide more genetic information for clinical diagnosis and treatment than karyotyping alone.
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Affiliation(s)
- Ping Huo
- Department of Reproductive Genetics, Hebei General Hospital, Shijiazhuang, Hebei 050051, P.R. China
| | - Qiuyan Luo
- Department of Reproductive Medicine, Tianjin Amcare Women and Children's Hospital, Tianjin 300381, P.R. China
| | - Juan Li
- Department of Reproductive Genetics, Hebei General Hospital, Shijiazhuang, Hebei 050051, P.R. China
| | - Baoquan Jiao
- Department of Reproductive Genetics, Bethune International Peace Hospital of The People's Liberation Army, Shijiazhuang, Hebei 050082, P.R. China
| | - Limin Rong
- Department of Reproductive Genetics, Hebei General Hospital, Shijiazhuang, Hebei 050051, P.R. China
| | - Jie Zhang
- Department of Reproductive Genetics, Bethune International Peace Hospital of The People's Liberation Army, Shijiazhuang, Hebei 050082, P.R. China
| | - Xiaohua Wu
- Department of Obstetrics and Gynecology Teaching and Research, Hebei Medical University, Shijiazhuang, Hebei 050017, P.R. China
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3
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Simard M, Laprise C, Girard SL. Impact of Paternal Age at Conception on Human Health. Clin Chem 2019; 65:146-152. [DOI: 10.1373/clinchem.2018.294421] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 11/05/2018] [Indexed: 12/14/2022]
Abstract
Abstract
BACKGROUND
The effect of maternal age at conception on various aspects of offspring health is well documented and often discussed. We seldom hear about the paternal age effect on offspring health, although the link is now almost as solid as with maternal age. The causes behind this, however, are drastically different between males and females.
CONTENT
In this review article, we will first examine documented physiological changes linked to paternal age effect. We will start with all morphological aspects of the testis that have been shown to be altered with aging. We will then move on to all the parameters of spermatogenesis that are linked with paternal age at conception. The biggest part of this review will focus on genetic changes associated with paternal age effects. Several studies that have established a strong link between paternal age at conception and the rate of de novo mutations will be reviewed. We will next discuss paternal age effects associated with telomere length and try to better understand the seemingly contradictory results. Finally, severe diseases that affect brain functions and normal development have been associated with older paternal age at conception. In this context, we will discuss the cases of autism spectrum disorder and schizophrenia, as well as several childhood cancers.
SUMMARY
In many Western civilizations, the age at which parents have their first child has increased substantially in recent decades. It is important to summarize major health issues associated with an increased paternal age at conception to better model public health systems.
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Affiliation(s)
- Mathieu Simard
- Centre Intersectoriel en Santé Durable, Université du Québec à Chicoutimi, Chicoutimi, Canada
| | - Catherine Laprise
- Centre Intersectoriel en Santé Durable, Université du Québec à Chicoutimi, Chicoutimi, Canada
| | - Simon L Girard
- Centre Intersectoriel en Santé Durable, Université du Québec à Chicoutimi, Chicoutimi, Canada
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4
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Bonomi M, Rochira V, Pasquali D, Balercia G, Jannini EA, Ferlin A. Klinefelter syndrome (KS): genetics, clinical phenotype and hypogonadism. J Endocrinol Invest 2017; 40:123-134. [PMID: 27644703 PMCID: PMC5269463 DOI: 10.1007/s40618-016-0541-6] [Citation(s) in RCA: 150] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 08/25/2016] [Indexed: 01/29/2023]
Abstract
Klinefelter Syndrome (KS) is characterized by an extreme heterogeneity in its clinical and genetic presentation. The relationship between clinical phenotype and genetic background has been partially disclosed; nevertheless, physicians are aware that several aspects concerning this issue are far to be fully understood. By improving our knowledge on the role of some genetic aspects as well as on the KS, patients' interindividual differences in terms of health status will result in a better management of this chromosomal disease. The aim of this review is to provide an update on both genetic and clinical phenotype and their interrelationships.
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Affiliation(s)
- M Bonomi
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Division of Endocrine and Metabolic Diseases & Laboratory of Endocrine and Metabolic Research, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - V Rochira
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via P. Giardini 1355, 41126, Modena, Italy.
- Azienda USL of Modena, NOCSAE, Via P. Giardini 1355, 41126, Modena, Italy.
| | - D Pasquali
- Department of Cardiothoracic and Respiratory Science, Second University of Naples, Naples, Italy
| | - G Balercia
- Division of Endocrinology, Department of Clinical and Molecular Sciences, Umberto I Hospital, Polytechnic University of Marche, Via Conca 71, 60126, Ancona, Italy
| | - E A Jannini
- Department of Systems Medicine, Tor Vergata University of Rome, Rome, Italy
| | - A Ferlin
- Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Padova, Italy
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5
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Bird RJ, Hurren BJ. Anatomical and clinical aspects of Klinefelter's syndrome. Clin Anat 2016; 29:606-19. [PMID: 26823086 DOI: 10.1002/ca.22695] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 01/07/2016] [Accepted: 01/15/2016] [Indexed: 12/29/2022]
Abstract
Klinefelter's syndrome, the most common sex disorder associated with chromosomal aberrations, is characterized by a plethora of clinical features. Parameters for diagnosis of the syndrome are constantly expanding as new anatomical and hormonal abnormalities are noted, yet Klinefelter's remains underdiagnosed and underreported. This review outlines the key anatomical characteristics associated with the syndrome, which are currently used for clinical diagnosis, or may provide means for improving diagnosis in the future. Clin. Anat. 29:606-619, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Rebecca J Bird
- Department of Anatomy, University of Otago, Dunedin, 9016, New Zealand
| | - Bradley J Hurren
- Department of Anatomy, University of Otago, Dunedin, 9016, New Zealand
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Sharma R, Agarwal A, Rohra VK, Assidi M, Abu-Elmagd M, Turki RF. Effects of increased paternal age on sperm quality, reproductive outcome and associated epigenetic risks to offspring. Reprod Biol Endocrinol 2015; 13:35. [PMID: 25928123 PMCID: PMC4455614 DOI: 10.1186/s12958-015-0028-x] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/09/2015] [Indexed: 12/14/2022] Open
Abstract
Over the last decade, there has been a significant increase in average paternal age when the first child is conceived, either due to increased life expectancy, widespread use of contraception, late marriages and other factors. While the effect of maternal ageing on fertilization and reproduction is well known and several studies have shown that women over 35 years have a higher risk of infertility, pregnancy complications, spontaneous abortion, congenital anomalies, and perinatal complications. The effect of paternal age on semen quality and reproductive function is controversial for several reasons. First, there is no universal definition for advanced paternal ageing. Secondly, the literature is full of studies with conflicting results, especially for the most common parameters tested. Advancing paternal age also has been associated with increased risk of genetic disease. Our exhaustive literature review has demonstrated negative effects on sperm quality and testicular functions with increasing paternal age. Epigenetics changes, DNA mutations along with chromosomal aneuploidies have been associated with increasing paternal age. In addition to increased risk of male infertility, paternal age has also been demonstrated to impact reproductive and fertility outcomes including a decrease in IVF/ICSI success rate and increasing rate of preterm birth. Increasing paternal age has shown to increase the incidence of different types of disorders like autism, schizophrenia, bipolar disorders, and childhood leukemia in the progeny. It is thereby essential to educate the infertile couples on the disturbing links between increased paternal age and rising disorders in their offspring, to better counsel them during their reproductive years.
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Affiliation(s)
- Rakesh Sharma
- Center for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA.
| | - Ashok Agarwal
- Center for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA.
| | - Vikram K Rohra
- Center for Reproductive Medicine, Cleveland Clinic, Cleveland, OH, USA.
| | - Mourad Assidi
- Center of Excellence in Genomic Medicine Research, King AbdulAziz University, Jeddah, Saudi Arabia.
- KACST Technology Innovation Center in Personalized Medicine at King AbdulAziz University, Jeddah, Saudi Arabia.
| | - Muhammad Abu-Elmagd
- Center of Excellence in Genomic Medicine Research, King AbdulAziz University, Jeddah, Saudi Arabia.
- KACST Technology Innovation Center in Personalized Medicine at King AbdulAziz University, Jeddah, Saudi Arabia.
| | - Rola F Turki
- KACST Technology Innovation Center in Personalized Medicine at King AbdulAziz University, Jeddah, Saudi Arabia.
- Obstetrics and Gynecology Department, King Abdulaziz University Hospital, Jeddah, Saudi Arabia.
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7
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Hanley AP, Blumenthal JD, Raitano Lee N, Baker EH, Clasen LS, Giedd JN. Brain and behavior in 48, XXYY syndrome. Neuroimage Clin 2015; 8:133-9. [PMID: 26106537 PMCID: PMC4473812 DOI: 10.1016/j.nicl.2015.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/23/2015] [Accepted: 04/08/2015] [Indexed: 11/14/2022]
Abstract
The phenotype of 48, XXYY syndrome (referred to as XXYY) is associated with characteristic but variable developmental, cognitive, behavioral and physical abnormalities. To discern the neuroanatomical phenotype of the syndrome, we conducted quantitative and qualitative analyses on MRI brain scans from 25 males with XXYY and 92 age and SES matched typically developing XY males. Quantitatively, males in the XXYY group had smaller gray and white matter volumes of the frontal and temporal lobes. Conversely, both gray and white matter volumes of the parietal lobe as well as lateral ventricular volume were larger in the XXYY group. Qualitatively, males in the XXYY group had a higher incidence of colpocephaly (84% vs. 34%, p ≤ 0.001), white matter lesions (25% vs. 5%, p = 0.007), and thin posterior body of the corpus callosum (28% vs. 3%, p = 0.001). The specificity of these findings may shed light on the role of the X and Y chromosomes in typical and atypical brain development and help provide direction for future studies of brain-behavior relationships in males with XXYY syndrome.
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Affiliation(s)
- Alli P. Hanley
- Child Psychiatry Branch, National Institute of Mental Health, NIH, DHHS, USA
| | | | | | - Eva H. Baker
- Department of Radiology and Imaging Sciences, Clinical Center, NIH, DHHS, USA
| | - Liv S. Clasen
- Child Psychiatry Branch, National Institute of Mental Health, NIH, DHHS, USA
| | - Jay N. Giedd
- Department of Psychiatry, University of California San Diego, USA
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8
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Skakkebaek A, Bojesen A, Kristensen MK, Cohen A, Hougaard DM, Hertz JM, Fedder J, Laurberg P, Wallentin M, Østergaard JR, Pedersen AD, Gravholt CH. Neuropsychology and brain morphology in Klinefelter syndrome - the impact of genetics. Andrology 2014; 2:632-40. [DOI: 10.1111/j.2047-2927.2014.00229.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/24/2014] [Accepted: 05/03/2014] [Indexed: 11/28/2022]
Affiliation(s)
- A. Skakkebaek
- Department of Endocrinology and Internal Medicine (MEA); Aarhus University Hospital; Aarhus Denmark
| | - A. Bojesen
- Department of Clinical Genetics; Vejle Hospital; Sygehus Lillebaelt; Vejle Denmark
| | - M. K. Kristensen
- Department of Mental Health; Odense University Clinic; Odense Denmark
| | - A. Cohen
- Section of Neonatal Screening and Hormones; Department of Clinical Biochemistry, Immunology and Genetics; Statens Serum Institute; Copenhagen Denmark
| | - D. M. Hougaard
- Section of Neonatal Screening and Hormones; Department of Clinical Biochemistry, Immunology and Genetics; Statens Serum Institute; Copenhagen Denmark
| | - J. M. Hertz
- Department of Clinical Genetics; Odense University Hospital; Odense Denmark
| | - J. Fedder
- Fertility Clinic; Department of Gynecology and Obstetrics; Odense University Hospital; Odense Denmark
| | - P. Laurberg
- Department of Endocrinology; Aalborg University Hospital; Aalborg Denmark
| | - M. Wallentin
- Center of Functionally Integrative Neuroscience; Aarhus University Hospital; Aarhus Denmark
- Center for Semiotics; Aarhus University; Aarhus Denmark
| | - J. R. Østergaard
- Centre for Rare Diseases; Department of Pediatrics; Aarhus University Hospital; Aarhus Denmark
| | - A. D. Pedersen
- Vejleford Rehabilitation Center; Stouby Denmark
- Department of Psychology and Behavioral Sciences; Aarhus University; Aarhus Denmark
| | - C. H. Gravholt
- Department of Endocrinology and Internal Medicine (MEA); Aarhus University Hospital; Aarhus Denmark
- Department of Molecular Medicine; Aarhus University Hospital; Aarhus Denmark
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9
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Giltay JC, Maiburg MC. Klinefelter syndrome: clinical and molecular aspects. Expert Rev Mol Diagn 2014; 10:765-76. [DOI: 10.1586/erm.10.63] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Maiburg M, Repping S, Giltay J. The genetic origin of Klinefelter syndrome and its effect on spermatogenesis. Fertil Steril 2012; 98:253-60. [PMID: 22749222 DOI: 10.1016/j.fertnstert.2012.06.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 06/10/2012] [Accepted: 06/12/2012] [Indexed: 01/18/2023]
Abstract
Klinefelter syndrome is the most prevalent chromosome abnormality and genetic cause of azoospermia in males. The availability of assisted reproductive technology (ART) has allowed men with Klinefelter syndrome to father their own genetic offspring. When providing ART to men with Klinefelter syndrome, it is important to be able to counsel them properly on both the chance of finding sperm and the potential effects on their offspring. The aim of this review is twofold: [1] to describe the genetic etiology of Klinefelter syndrome and [2] to describe how spermatogenesis occurs in men with Klinefelter syndrome and the consequences this has for children born from men with Klinefelter syndrome.
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Affiliation(s)
- Merel Maiburg
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands.
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11
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Uroz L, Templado C. Meiotic non-disjunction mechanisms in human fertile males. Hum Reprod 2012; 27:1518-24. [DOI: 10.1093/humrep/des051] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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12
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Copy number variants for schizophrenia and related psychotic disorders in Oceanic Palau: risk and transmission in extended pedigrees. Biol Psychiatry 2011; 70:1115-21. [PMID: 21982423 PMCID: PMC3224197 DOI: 10.1016/j.biopsych.2011.08.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 07/08/2011] [Accepted: 08/02/2011] [Indexed: 12/31/2022]
Abstract
BACKGROUND We report on copy number variants (CNVs) found in Palauan subjects ascertained for schizophrenia and related psychotic disorders in extended pedigrees in Palau. We compare CNVs found in this Oceanic population with those seen in other samples, typically of European ancestry. Assessing CNVs in Palauan extended pedigrees yields insight into the evolution of risk CNVs, such as how they arise, are transmitted, and are lost from populations by stochastic or selective processes, none of which are easily measured from case-control samples. METHODS DNA samples from 197 subjects affected with schizophrenia and related psychotic disorders, 185 of their relatives, and 159 control subjects were successfully characterized for CNVs using Affymetrix Genomewide Human SNP Array 5.0. RESULTS Copy number variants thought to be associated with risk for schizophrenia and related disorders also occur in affected individuals in Palau, specifically 15q11.2 and 1q21.1 deletions, partial duplication of IL1RAPL1 (Xp21.3), and chromosome X duplications (Klinefelter's syndrome). Partial duplication within A2BP1 appears to convey an eightfold increased risk in male subjects (95% confidence interval, .8-84.4) but not female subjects (odds ratio = .4, 95% confidence interval, .03-4.9). Affected-only linkage analysis using this variant yields a logarithm of the odds score of 3.5. CONCLUSIONS This study reveals CNVs that confer risk to schizophrenia and related psychotic disorders in Palau, most of which have been previously observed in samples of European ancestry. Only a few of these CNVs show evidence that they have existed for many generations, consistent with risk variants diminishing reproductive success.
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Duan T, Yang QL, Wang L, Shi QH, Yu DX. [Correlation analysis between meiotic recombination frequencies and age in human spermatocyte]. YI CHUAN = HEREDITAS 2011; 33:725-30. [PMID: 22049685 DOI: 10.3724/sp.j.1005.2011.00725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Faithful meiotic recombination is essential for the segregation of homologous chromosomes and the formation of normal haploid gametes. Little is known about the mechanism of meiotic recombination in human germ cells. MLHl (a DNA mismatch repair protein) foci on synaptonemal complexes (SCs) at prophase I of meiosis can be used to examine recombination frequency. In 10 fertile men, the mean number of MLH1 foci per cell in all donors was 49.4 with a range from 33 to 63. There was significant variation in the recombination frequency found among 10 normal individuals: the mean frequencies of chromosomal recombination foci ranged from 47 to 52.7. The bivalents without recombination focus were rare, with a frequency of only 0.4%. Thus, achiasmate chromosomes appeared to be rare in human male meiosis. Spearman correlation analysis between age and the frequencies of recombination foci failed to get any significantly statistical correlation, suggesting that aging contributes nothing to the variation among individuals.
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Affiliation(s)
- Tao Duan
- Department of Urology, First Affiliated Hospital, Anhui Medial University, Hefei 230022, China
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14
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XCI in preimplantation mouse and human embryos: first there is remodelling…. Hum Genet 2011; 130:203-15. [PMID: 21647603 PMCID: PMC3132436 DOI: 10.1007/s00439-011-1014-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 05/19/2011] [Indexed: 12/21/2022]
Abstract
Female eutherians silence one of their X chromosomes to accomplish an equal dose of X-linked gene expression compared with males. The mouse is the most widely used animal model in XCI research and has proven to be of great significance for understanding the complex mechanism of X-linked dosage compensation. Although the basic principles of XCI are similar in mouse and humans, differences exist in the timing of XCI initiation, the genetic elements involved in XCI regulation and the form of XCI in specific tissues. Therefore, the mouse has its limitations as a model to understand early human XCI and analysis of human tissues is required. In this review, we describe these differences with respect to initiation of XCI in human and mouse preimplantation embryos, the extra-embryonic tissues and the in vitro model of the epiblast: the embryonic stem cells.
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Abstract
Childhood overweight and obesity is highly prevalent within society. In the majority of individuals, weight gain is the result of exposure to an 'obesogenic' environment, superimposed on a background of genetic susceptibility brought about by evolutionary adaptation. These individuals tend to be tall in childhood with a normal final adult height, as opposed to those who have an underlying monogenic cause where short stature is more common (although not universal). Identifying genetic causes of weight gain, or tall stature and overgrowth, within this setting can be extremely problematic and yet it is imperative that clinicians remain alert, as identification of a genetic diagnosis has major implications for the individual, family and potential offspring. Alongside this, the recognition of new genetic mutations in this area is furthering our knowledge on the important mechanisms that regulate childhood growth and body composition. This review describes the genetic syndromes associated with obesity and overgrowth.
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Affiliation(s)
- Matthew A Sabin
- Murdoch Childrens Research Institute, Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia.
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16
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Fonseka K, Griffin D. Is There a Paternal Age Effect for Aneuploidy? Cytogenet Genome Res 2011; 133:280-91. [DOI: 10.1159/000322816] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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17
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Ioannou D, Griffin DK. Male fertility, chromosome abnormalities, and nuclear organization. Cytogenet Genome Res 2010; 133:269-79. [PMID: 21088381 DOI: 10.1159/000322060] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Numerous studies have implicated the role of gross genomic rearrangements in male infertility, e.g., constitutional aneuploidy, translocations, inversions, Y chromosome deletions, elevated sperm disomy, and DNA damage. The primary purpose of this paper is to review male fertility studies associated with such abnormalities. In addition, we speculate whether altered nuclear organization, another chromosomal/whole genome-associated phenomenon, is also concomitant with male factor infertility. Nuclear organization has been studied in a range of systems and implicated in several diseases. For many applications the measurement of the relative position of chromosome territories is sufficient to determine patterns of nuclear organization. Initial evidence has suggested that, unlike in the more usual 'size-related' or 'gene density-related' models, mammalian (including human) sperm heads display a highly organized pattern including a chromocenter with the centromeres located to the center of the nucleus and the telomeres near the periphery. More recent evidence, however, suggests there may be size- and gene density-related components to nuclear organization in sperm. It seems reasonable to hypothesize therefore that alterations in this pattern may be associated with male factor infertility. A small handful of studies have addressed this issue; however, to date it remains an exciting avenue for future research with possible implications for diagnosis and therapy.
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Affiliation(s)
- D Ioannou
- School of Biosciences, University of Kent, Canterbury, UK
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18
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Tuttelmann F, Gromoll J. Novel genetic aspects of Klinefelter's syndrome. Mol Hum Reprod 2010; 16:386-95. [DOI: 10.1093/molehr/gaq019] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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19
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Abstract
Chromosome anomalies are extraordinarily common in human gametes, with approximately 21% of oocytes and 9% of spermatozoa abnormal. The types of abnormalities are quite different since most abnormal oocytes are aneuploid, whereas the majority of abnormalities in spermatozoa are structural. Chromosomes 21 and 22 (the smallest chromosomes) are over-represented in aneuploid gametes in both oocytes and sperm. Chromosome 16 is also frequently observed in aneuploid oocytes, whereas the sex chromosomes are particularly predisposed to non-disjunction in human sperm. Maternal age is clearly the most significant factor in the aetiology of aneuploidy; theories about the cause of the maternal age effect are discussed. Paternal age does not have a dramatic effect on the frequency of aneuploid sperm; there is some evidence for a modest increase in the frequency of sex chromosomal aneuploidy. Meiotic recombination has a significant effect on the genesis of aneuploidy in both females and males. New techniques, which allow the analysis of recombination along the synaptonemal complex, have yielded interesting new information in healthy and infertile individuals. There is a link between infertility and the genesis of chromosome abnormalities. Future studies will unravel more of the underlying causal factors.
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Affiliation(s)
- Renée H Martin
- University of Calgary, Department of Medical Genetics, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1.
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Martin RH. Cytogenetic determinants of male fertility. Hum Reprod Update 2008; 14:379-90. [PMID: 18535003 PMCID: PMC2423221 DOI: 10.1093/humupd/dmn017] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 04/18/2008] [Accepted: 04/29/2008] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Cytogenetic abnormalities have been known to be important causes of male infertility for decades. METHODS Research publications from 1978 to 2008, from PubMed, have been reviewed. RESULTS These studies have greatly improved our information on somatic chromosomal abnormalities such as translocations, inversions and sex chromosomal anomalies, and their consequences to the cytogenetic make-up of human sperm. Also, we have learned that infertile men with a normal somatic karyotype have an increased risk of chromosomally abnormal sperm and children. New techniques such as single sperm typing and synaptonemal complex analysis have provided valuable insight into the association between meiotic recombination and the production of aneuploid sperm. These meiotic studies have also unveiled errors of chromosome pairing and synapsis, which are more common in infertile men. CONCLUSIONS These studies allow us to provide more precise information to infertile patients, and further our basic knowledge in the causes of male infertility.
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Affiliation(s)
- R H Martin
- Department of Medical Genetics, University of Calgary, Room 287, Heritage Medical Research Building, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1.
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Sun F, Mikhaail-Philips M, Oliver-Bonet M, Ko E, Rademaker A, Turek P, Martin R. The relationship between meiotic recombination in human spermatocytes and aneuploidy in sperm. Hum Reprod 2008; 23:1691-7. [DOI: 10.1093/humrep/den027] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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Boks MPM, de Vette MHT, Sommer IE, van Rijn S, Giltay JC, Swaab H, Kahn RS. Psychiatric morbidity and X-chromosomal origin in a Klinefelter sample. Schizophr Res 2007; 93:399-402. [PMID: 17459660 DOI: 10.1016/j.schres.2007.03.015] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Revised: 03/13/2007] [Accepted: 03/17/2007] [Indexed: 11/29/2022]
Abstract
The presence of an additional X-chromosome in Klinefelter patients provides an opportunity to study the influence of this chromosome on psychiatric disorders. Previous studies have reported an excess of Klinefelter patients in psychiatric patient groups. We report an increased prevalence of psychiatric disorders including psychotic disorders in a sample of Klinefelter patients but could not find evidence of an effect of the parental origin of the extra X-chromosome on the psychiatric phenotype. Nevertheless, these findings provide further support for the role of the X-chromosome in the susceptibility to psychiatric disorders in general and psychotic disorders in particular.
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Affiliation(s)
- Marco P M Boks
- Rudolf Magnus Institute of Neuroscience, Department of Psychiatry, Utrecht, The Netherlands.
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Stemkens D, Roza T, Verrij L, Swaab H, van Werkhoven MK, Alizadeh BZ, Sinke RJ, Giltay JC. Is there an influence of X-chromosomal imprinting on the phenotype in Klinefelter syndrome? A clinical and molecular genetic study of 61 cases. Clin Genet 2006; 70:43-8. [PMID: 16813603 DOI: 10.1111/j.1399-0004.2006.00635.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Studies on Turner syndrome suggested the presence of X-chromosomal-imprinted genes involved in social and verbal cognition. Imprinted genes on autosomes were shown to affect growth. Could imprinting of such genes on the X chromosome also influence psychomotor development and growth in men with Klinefelter syndrome (KS), who have a supernumerary X? We recorded anthropometric and psychomotor development parameters for 61 males with KS (age range 2-56 years). In 54 cases, we were able to assess intelligence quotient (IQ) and found that impaired speech - and motor developmental problems were reported significantly more often in the paternal X - than in the maternal X group (P = 0.02). We found some significant (P < 0.05) increased body size parameters in the paternal X group, which concurs with data reporting a growth promoting influence of paternally derived genes. Our results suggest X-chromosomal imprinting occurs in males with KS.
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Affiliation(s)
- D Stemkens
- Department of Biomedical Genetics, University Medical Center, Utrecht, The Netherlands
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24
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Buwe A, Guttenbach M, Schmid M. Effect of paternal age on the frequency of cytogenetic abnormalities in human spermatozoa. Cytogenet Genome Res 2006; 111:213-28. [PMID: 16192697 DOI: 10.1159/000086892] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Accepted: 05/17/2005] [Indexed: 11/19/2022] Open
Abstract
Many surveys have been performed to find etiological relationships between pregnancy outcome and specific risk factors, such as exposure to chemicals and radiation or parental age. Advanced maternal age is a strong risk factor for trisomic pregnancies, albeit there are considerable variations among the different chromosomes. The definite incidence of the various structural and numerical chromosome aberrations in spontaneous abortions and liveborns is well known, as well as the rate of maternally and paternally derived rearrangements. Nevertheless studies have failed to assert an age-dependent risk for men fathering chromosomally abnormal children. New techniques using fluorescence in situ hybridization render it possible to analyze spermatozoa directly for numerical and, to some extent, for structural aberrations. This article compiles the findings of studies on human spermatozoa over the last few years.
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Affiliation(s)
- A Buwe
- Department of Human Genetics, Biozentrum, University of Würzburg, Würzburg, Germany
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25
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Martin RH. Mechanisms of nondisjunction in human spermatogenesis. Cytogenet Genome Res 2006; 111:245-9. [PMID: 16192700 DOI: 10.1159/000086895] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 02/16/2005] [Indexed: 11/19/2022] Open
Abstract
A reduction in recombination in the pseudoautosomal region is associated with an increased frequency of aneuploid 24,XY human sperm. Similarly, individuals with paternally derived Klinefelter syndrome (47,XXY) also have a paucity of recombination in the chromosomes that have undergone nondisjunction. Meiotic studies using newly developed immunocytogenetic techniques have demonstrated errors of chromosome synapsis and significantly reduced recombination in infertile men with nonobstructive azoospermia. These men have an increased risk of aneuploidy in sperm that have been surgically removed from the testes. Thus, evidence is starting to accumulate that reduced recombination has a marked effect on the generation of aneuploid sperm.
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Affiliation(s)
- R H Martin
- Department of Medical Genetics, University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Canada.
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26
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Arnedo N, Templado C, Sánchez-Blanque Y, Rajmil O, Nogués C. Sperm aneuploidy in fathers of Klinefelter's syndrome offspring assessed by multicolour fluorescent in situ hybridization using probes for chromosomes 6, 13, 18, 21, 22, X and Y. Hum Reprod 2005; 21:524-8. [PMID: 16199425 DOI: 10.1093/humrep/dei321] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND It is still unclear if a recurrence risk would exist in fathers of an aneuploid offspring of paternal origin. We have studied disomy frequencies in spermatozoa from fathers having Klinefelter syndrome (KS) offspring or miscarriages. The effect of paternal age on sperm disomy percentages is also analysed. METHODS Parental origin of 17 KS patients was carried out by amplification of X chromosome polymorphisms. Spermatozoa from their fathers were studied by multicolour fluorescent in situ hybridisation (FISH) using probes for chromosomes 6, 13, 18, 21, 22, X and Y. RESULTS In 53% of KS cases studied the additional X chromosome was of paternal origin. The paternally transmitted KS group of fathers showed significantly higher frequencies for XY disomy sperm as compared to fathers of the maternal-origin group. A correlation between paternal age and XY disomy frequencies was only found in the paternally derived cases. In contrast, similar disomy frequencies for all autosomes analysed were found in both groups of fathers. CONCLUSIONS XY disomy frequencies increase with advancing paternal age only in fathers with paternally inherited KS offspring.
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Affiliation(s)
- Núria Arnedo
- Departament de Biologia Cellular, Fisiologia i Immunologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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Miharu N. Chromosome abnormalities in sperm from infertile men with normal somatic karyotypes: oligozoospermia. Cytogenet Genome Res 2005; 111:347-51. [PMID: 16192714 DOI: 10.1159/000086909] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Accepted: 01/19/2005] [Indexed: 11/19/2022] Open
Abstract
Recently, intracytoplasmic sperm injection (ICSI) has been extremely successful for the treatment of male infertility. However, transmission of cytogenetic defects to offspring is a great concern. There are two types of cytogenetic problems in patients seeking ICSI; one is the transmission of genetic defects from patients with constitutional chromosomal abnormalities and the second is the generation of de novo defects in infertile men. Generally about 5.1% of infertile men have chromosomal abnormalities. Among such infertile men, men with severe spermatogenesis defects, including oligozoospermia and azoospermia, are subjects for ICSI. Therefore it is very important to obtain cytogenetic information in these infertile patients. Furthermore, oligozoospermic men with a normal somatic karyotype also have increased frequencies of sperm chromosome abnormalities. Oligozoospermia is usually associated with other sperm alterations, for example oligoasthenozoospermia, oligoteratozoospemia and oligoasthenoteratozoospermia. In this review, the relationship between sperm concentration and sperm aneuploidy frequencies has been analyzed. The inverse correlation between the frequency of sperm aneuploidy and concentration has been reported in extensive studies. Especially in severe oligozoospermia, a significantly higher frequency of sex chromosome aneuploidy has been observed and this has been corroborated in recent clinical outcome data of ICSI.
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Affiliation(s)
- N Miharu
- Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
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Kovaleva NV, Mutton DE. Epidemiology of double aneuploidies involving chromosome 21 and the sex chromosomes. Am J Med Genet A 2005; 134A:24-32. [PMID: 15704133 DOI: 10.1002/ajmg.a.30306] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The chance of two chromosome abnormalities occurring in one conceptus is very small. However, some authors have suggested that double aneuplodies (DAs) might be more common than the product of their individual frequencies. The nonrandomness of such DA events was considered to be evidence that nondisjunction (NDJ) may be genetically determined. Data collected from the National Down syndrome Cytogenetic Register (NDSCR) in England and Wales and from the literature indicate that the frequencies of all nonmosaic DAs, except for 48,XXY,+21, are lower than expected, probably because of strong intrauterine selection against such pregnancies. Collectively, we identified 52 cases of nonmosaic 48,XXY,+21; 28 cases of 48,XYY,+21; and 14 cases of 48,XXX,+21 in liveborns and 13 cases of 48,XXY,+21; four cases of 48,XYY,+21; and two cases of 48,XXX,+21 after prenatal diagnoses. Among these cases, analysis of the published unbiased cytogenetic surveys of liveborn DS revealed 24 cases of 48,XXY,+21; nine cases of 48,XYY,+21; and seven cases of 48,XXX,+21. These figures are different from the expected proportion of 1:1:1 (P < 0.001), with carriers of XXY overrepresented in the group of carriers of DA. Mechanisms put forth to account for the higher occurrence of 48,XXY,+21 may include greater accessibility of disomic ovum to Y-carrying sperm, and promotion of NDJ in ovum by Y-bearing sperm. 48,XXY,+21 DA was found to be age-dependent, as the proportion of mothers over age 35 (x = 33.0) was increased over the general population. This is in contrast to the apparently age-independent 48,XYY,+21 DA, with a mean maternal age of 24.7 (P < 0.001). Paternal ages were also remarkably different between the groups, with a mean age of 37.9 in 48,XXY,+21 cases and a mean age of 27.9 in 48,XYY,+21 cases (P < 0.01). Maternal age-related factors, rather than genetic predisposition, may play a more important role in the etiology of the most common DA, 48,XXY,+21.
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Affiliation(s)
- Natalia V Kovaleva
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.
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Smith JL, Garry VF, Rademaker AW, Martin RH. Human sperm aneuploidy after exposure to pesticides. Mol Reprod Dev 2004; 67:353-9. [PMID: 14735496 DOI: 10.1002/mrd.20022] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study examined the effect of paternal environmental exposure to pesticides on the frequency of aneuploidy in human sperm. To determine if the chromosome number in germ cells was altered by paternal exposure, multicolor fluorescence in situ hybridization (FISH) analysis was utilized to measure aneuploidy frequencies in the sperm of 40 men (20 exposed, 20 controls). Samples were coded for "blind analysis" to eliminate scorer bias. Aneuploidy and diploidy frequencies were assessed for chromosomes 13, 21, X, and Y. A minimum of 10,000 sperm was scored per donor per chromosome probe with a total of 809,935 sperm scored. Hybridization efficiency was 99%. There were no significant differences in aneuploidy or diploidy frequencies between exposed and control groups, suggesting that the pesticides did not increase the risk of numerical chromosomal abnormalities in these men.
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Affiliation(s)
- Jena L Smith
- Department of Medical Genetics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Sloter E, Nath J, Eskenazi B, Wyrobek AJ. Effects of male age on the frequencies of germinal and heritable chromosomal abnormalities in humans and rodents. Fertil Steril 2004; 81:925-43. [PMID: 15066442 DOI: 10.1016/j.fertnstert.2003.07.043] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2003] [Revised: 07/09/2003] [Accepted: 07/09/2003] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To review evidence regarding the effects of male age on germinal and heritable chromosomal abnormalities using available human and rodent studies and to evaluate possible underlying mechanisms. DESIGN Review of English language-published research using MEDLINE database, excluding case reports and anecdotal data. RESULT(S) There was little evidence from offspring or germ cell studies for a generalized male age effect on autosomal aneuploidy, except in rodents. Sex chromosomal nondisjunction increased with age in both human and rodent male germ cells. Both human and rodent data showed age-related increases in the number of sperm with chromosomal breaks and fragments and suggest that postmeiotic cells are particularly vulnerable to the effects of aging. Translocation frequencies increased with age in murine spermatocytes, at rates comparable to mouse and human somatic cells. Age-related mechanisms of induction may include accumulation of environmental damage, reduced efficiency of DNA repair, increased genomic instability, genetic factors, hormonal influences, suppressed apoptosis, or decreased effectiveness of antioxidants and micronutrients. CONCLUSION(S) The weight of evidence suggests that the increasing trend toward fathering at older ages may have significant effects on the viability and genetic health of human pregnancies and offspring, primarily as a result of structural chromosomal aberrations in sperm.
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Affiliation(s)
- Eddie Sloter
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Schneider M, Forrester S, Crain V, Kimonis V. A further case of coincidental Prader-Willi and Klinefelter syndromes. ACTA ACUST UNITED AC 2004; 126A:213-4. [PMID: 15057989 DOI: 10.1002/ajmg.a.20462] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
Genetic risks related to paternal age should be of interest to clinical andrologists counselling older men who wish to father a child. Theoretically, the number of (pre-meiotic) mitotic cell divisions during spermatogenesis and their remarkable increase with ageing compared with oogenesis would be in favour of genetic risks for the offspring of older men. But for numerical and structural chromosomal anomalies, such an influence of paternal age has not been found. However, in several autosomal dominant disorders affecting three specific genes (fibroblast growth factor receptor 2 and 3, RET proto-oncogene) the risk for a child to be affected increases with paternal age at time of birth. For other autosomal dominant -X chromosomal dominant or recessive disorders, the available data are sufficient to support the concept of a positive relationship between paternal age and de novo gene mutations. Studies analysing gene sequences of affected children and their parents would allow further evaluation of this topic. The impact of paternal age on disorders with a complex genetic background, however, is a matter of debate. A significant effect of paternal age could not be shown for nonfamilial Alzheimer's disease, congenital heart defects, nonfamilial schizophrenia, acute lymphoblastic leukaemia or prostate cancer.
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Affiliation(s)
- A Jung
- Centre of Dermatology and Andrology, Justus Liebig University, Giessen, Germany.
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33
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Shi Q, Spriggs E, Field LL, Rademaker A, Ko E, Barclay L, Martin RH. Absence of age effect on meiotic recombination between human X and Y chromosomes. Am J Hum Genet 2002; 71:254-61. [PMID: 12046006 PMCID: PMC379158 DOI: 10.1086/341559] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2002] [Accepted: 05/01/2002] [Indexed: 11/03/2022] Open
Abstract
Recombination between the X and Y chromosomes is limited to the pseudoautosomal region and is necessary for proper segregation of the sex chromosomes during spermatogenesis. Failure of the sex chromosomes to disjoin properly during meiosis can result in individuals with a 47,XXY constitution, and approximately one-half of these result from paternal nondisjunction at meiosis I. Analysis of individuals with paternally derived 47,XXY has shown that the majority are the result of meiosis in which the X and Y chromosomes have failed to recombine. Our studies of sperm have demonstrated that aneuploid 24,XY sperm have a decreased recombination frequency, compared with that of normal sperm. Some studies have indicated a relationship of increased paternal age with 47,XXY offspring and with the production of XY disomic sperm, whereas others have failed to find such relationships. To determine whether there is a relationship between paternal age and recombination in the pseudoautosomal region, single-sperm genotyping was performed to measure the frequency of recombination between a sex-specific locus, STS/STS pseudogene, and a pseudoautosomal locus, DXYS15, in younger men (age < or =30 years) compared with older men (age > or =50 years). A total of 2,329 sperm cells were typed by single-sperm PCR in 20 men who were heterozygous for the DXYS15 locus (1,014 sperm from 10 younger men and 1,315 sperm from 10 older men). The mean recombination frequency was 39.2% in the younger men and 37.8% in the older men. There was no heterogeneity in the frequency of recombination rates. There was no significant difference between the recombination frequencies among the younger men and those among the older men, when analyzed by the clustered binomial Z test (Z=.69, P=.49). This result suggests that paternal age has no effect on the recombination frequency in the pseudoautosomal region.
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Affiliation(s)
- Qinghua Shi
- Department of Medical Genetics, Faculty of Medicine, Alberta Children's Hospital, University of Calgary, 1820 Richmond Road SW, Calgary, Alberta, Canada T2T 5C7
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Eskenazi B, Wyrobek AJ, Kidd SA, Lowe X, Moore D, Weisiger K, Aylstock M. Sperm aneuploidy in fathers of children with paternally and maternally inherited Klinefelter syndrome. Hum Reprod 2002; 17:576-83. [PMID: 11870106 DOI: 10.1093/humrep/17.3.576] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND It is unclear whether frequency of sperm aneuploidy is associated with risk of fathering children with trisomy. METHODS We recruited 36 families with a boy with Klinefelter syndrome (KS), interviewed the fathers about their exposures and medical history, received a semen sample from each father, and collected blood samples from the mother, father and child. We applied a multicolour fluorescent in-situ hybridization assay to compare the frequencies of sperm carrying XY aneuploidy and disomies X, Y and 21 in fathers of maternally and paternally inherited KS cases. RESULTS Inheritance of the extra X chromosome was paternal in 10 and maternal in 26 families. Fathers of paternal KS cases produced higher frequencies of XY sperm (P = 0.02) than fathers of maternal KS cases. After controlling for age, the major confounding variable, the difference between the two groups was no longer significant (P less-than-or-equal 0.2). Also, there were no significant differences between the parental origin groups for disomy X, Y or 21. CONCLUSIONS Men who fathered a child with a Klinefelter syndrome produced higher frequencies of XY sperm aneuploidy, which is explained, in part, by both paternal age and parent of origin.
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Affiliation(s)
- B Eskenazi
- School of Public Health, University of California, Berkeley, CA 94720, USA.
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35
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Lowe X, Eskenazi B, Nelson DO, Kidd S, Alme A, Wyrobek AJ. Frequency of XY sperm increases with age in fathers of boys with Klinefelter syndrome. Am J Hum Genet 2001; 69:1046-54. [PMID: 11582569 PMCID: PMC1274351 DOI: 10.1086/323763] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2001] [Accepted: 08/13/2001] [Indexed: 11/03/2022] Open
Abstract
With increasing availability of drugs for impotence and advanced reproductive technologies for the treatment of subfertility, more men are fathering children at advanced ages. We conducted a study of the chromosomal content of sperm of healthy men aged 24-57 years to (a) determine whether father's age was associated with increasing frequencies of aneuploid sperm including XY, disomy X, disomy Y, disomy 21, and sperm diploidy, and (b) examine the association between the frequencies of disomy 21 and sex-chromosomal aneuploidies. The study group consisted of 38 fathers of boys with Klinefelter syndrome (47, XXY) recruited nationwide, and sperm aneuploidy was assessed using multicolor X-Y-21 sperm FISH ( approximately 10,000 sperm per donor). Paternal age was significantly correlated with the sex ratio of sperm (Y/X; P=.006) and with the frequency of XY sperm (P=.02), with a clear trend with age by decades (P<.006). Compared with fathers in their 20s (who had an average frequency of 7.5 XY sperm per 10,000), the frequencies of XY sperm were 10% higher among fathers in their 30s, 31% higher among those in their 40s, and 160% higher among those in their 50s (95% CI 69%-300%). However, there was no evidence for age effects on frequencies of sperm carrying nullisomy sex; disomies X, Y, or 21; or meiosis I or II diploidies. The frequencies of disomy 21 sperm were significantly associated with sex-chromosomal aneuploidy (P=.04)-in particular, with disomy X (P=.004), but disomy 21 sperm did not preferentially carry either sex chromosome. These findings suggest that older fathers produce higher frequencies of XY sperm, which may place them at higher risk of fathering boys with Klinefelter syndrome, and that age effects on sperm aneuploidy are chromosome specific.
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Affiliation(s)
- Xiu Lowe
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
| | - Brenda Eskenazi
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
| | - David O. Nelson
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
| | - Sharon Kidd
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
| | - Angela Alme
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
| | - Andrew J. Wyrobek
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, CA, and School of Public Health, University of California, Berkeley
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36
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Bosch M, Rajmil O, Martínez-Pasarell O, Egozcue J, Templado C. Linear increase of diploidy in human sperm with age: a four-colour FISH study. Eur J Hum Genet 2001; 9:533-8. [PMID: 11464245 DOI: 10.1038/sj.ejhg.5200659] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2000] [Revised: 03/23/2001] [Accepted: 04/03/2001] [Indexed: 11/09/2022] Open
Abstract
The aim of this study was to determine if donor age is associated with an increased incidence of diploidy and of disomy for the sex chromosomes and for chromosomes 6 and 21. We used simultaneous fluorescence in situ hybridisation (FISH) for chromosomes 6, 21, X and Y in sperm from 18 healthy donors, aged 24-74 years (mean 48.8 years). A total of 194 024 sperm were analysed, with a minimum of 10 000 sperm scored for each donor. Our results indicate a significant increase of the level of diploidy (P=0.002), and a marginal significance of total sex chromosome disomy (P=0.055) with age. No increase was observed for disomies XX, YY, XY, 21 or 6. The percentages of increase for disomy and for diploidy ranged from 0.3 to 17% for each 10-year period. Chromosomes 6 and 21 did not segregate preferentially with the X or Y chromosomes. Our findings show a linear trend association between age and diploidy in human males.
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Affiliation(s)
- M Bosch
- Departament de Biologia Cel.lular, Fisiologia i Immunologia, Facultat de Medicina, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
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37
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Shi Q, Spriggs E, Field LL, Ko E, Barclay L, Martin RH. Single sperm typing demonstrates that reduced recombination is associated with the production of aneuploid 24,XY human sperm. AMERICAN JOURNAL OF MEDICAL GENETICS 2001; 99:34-8. [PMID: 11170091 DOI: 10.1002/1096-8628(20010215)99:1<34::aid-ajmg1106>3.0.co;2-d] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To account for the increased proportion of paternal nondisjunction in 47,XXY males as compared to other trisomies, it has been suggested that the XY bivalent, with its reduced region of homology, is particularly susceptible to nondisjunction. Molecular studies of liveborn Klinefelter syndrome (47,XXY) individuals have reported an association between the absence of recombination in the pseudoautosomal region and nondisjunction of the XY bivalent. In this study we examined single sperm from a normal 46,XY male to determine if there is any alteration in the recombination frequency of aneuploid disomic 24,XY sperm compared to unisomic sperm (23,X or Y). Two DNA markers STS/STS pseudogene and DXYS15 were typed in sperm from a heterozygous man to determine if recombination had occurred in the pseudoautosomal region. Individual unisomic sperm (23,X or Y) were isolated using a FACStar(Plus) flow cytometer into PCR tubes. To identify disomic 24,XY sperm, 3-colour FISH analysis was performed with probes for chromosomes X,Y and 1. The 24,XY cells were identified using fluorescence microscopy, each disomic sperm was scraped off the slide using a glass needle attached to a micromanipulator and then put into a PCR tube. Hemi-nested PCR analysis of the two markers was performed to determine the frequency of recombination. A total of 329 unisomic sperm and 150 disomic sperm have been typed. The frequency of recombination between the two DNA markers was 38.3% for the unisomic sperm, similar to frequencies previously reported. The 24,XY disomic sperm had an estimated recombination frequency of 25.3%, however, a highly significant decrease compared to the unisomic 23,X or 23,Y sperm (chi(2) = 10.7, P = 0.001). This direct analysis of human sperm indicates that lack of recombination in the pseudoautosomal region is a significant cause of XY nondisjunction and thus Klinefelter syndrome.
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Affiliation(s)
- Q Shi
- Department of Medical Genetics, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Affiliation(s)
- A Mäkinen
- University of Helsinki, Department of Animal Science, Finland
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Asada H, Sueoka K, Hashiba T, Kuroshima M, Kobayashi N, Yoshimura Y. The effects of age and abnormal sperm count on the nondisjunction of spermatozoa. J Assist Reprod Genet 2000; 17:51-9. [PMID: 10754784 PMCID: PMC3455190 DOI: 10.1023/a:1009454114973] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The effect of paternal age on the nondisjunction of sex chromosomes is controversial. Also, the prevalence of chromosomal anomalies in infertile patients is controversial, it has been reported that the sex chromosomal aneuploidy rate following treatment with intracytoplasmic sperm injection (ICSI) is higher than in naturally conceived pregnancies. We investigated the influence of paternal age and oligozoospermia on the nondisjunction of spermatozoa. METHODS We determined the rate of aneuploidy for gonosomes and autosomes, using two-color fluorescence in situ hybridization (FISH) of the X and Y chromosomes and chromosomes 12 and 18 in 10 donors under 25 years of age who had a normal sperm count (> or = 20 x 10(6)/ml), 10 donors over the age of 39 years with idiopathic infertility and normozoospermia (> or = 20 x 10(6)/ml), and 5 oligozoospermic donors (< 20 x 10(6)/ml). RESULTS There was no obvious relationship between increasing age and autosomal disomy (disomy 12 and disomy 18). Neither autosomal disomy nor diploidy was increased in any group. The frequency of X-, Y-, XX-, and YY-bearing sperm did not differ significantly among groups, but the frequency of XY-bearing sperm was significantly higher in the older infertile group than in the control donors. CONCLUSIONS The incidence of nondisjunction of paternal sex chromosome in meiosis I was higher in older men with idiopathic infertility. The present results suggest that the risk of producing XXY fetuses is higher among men > 39 years of age with idiopathic infertility.
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Affiliation(s)
- H Asada
- Department of Obstetrics & Gynecology, Keio University School of Medicine, Tokyo, Japan
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Abstract
Several molecular and clinical similarities have been detected in Alzheimer's disease (AD) and Down syndrome (DS). The most remarkable feature is abnormal accumulation of beta-amyloid in the brains of both individuals affected with AD and aging DS patients followed by dementia. In addition, AD patients exhibit dermatoglyphic patterns similar to those in DS, and late maternal age is a risk factor in both diseases. AD and DS could be related genetically because AD families exhibit a higher rate of DS cases and vice versa. Although numerous discoveries have been made in the elucidation of the etiopathogenic factors in AD and DS, little progress has been achieved in understanding the origin of the common features of the two diseases. This article reviews clinical and molecular similarities in DS and AD and also chromosome 21 studies in both diseases. A new hypothesis explaining the association between AD and DS is suggested, and this hypothesis is based on the poorly understood molecular phenomenon of aberrant meiotic recombination. Aberration in meiotic recombination has been consistently detected in chromosomal diseases including trisomy 21 and sex chromosomes. There are no studies dedicated to meiotic recombination in genetic diseases; however, evidence for disturbed recombination has been documented in several neurological diseases such as Huntington's disease, myotonic dystrophy, and fragile X syndrome. Interestingly, the rate of trisomic XXY children born to mothers transmitting fragile X mutation is higher than expected. This finding suggests that AD could be associated with DS in a similar way to which fragile X syndrome is related to trisomy of sex chromosomes. Based on analogy with fragile X syndrome, it can be predicted that AD should demonstrate aberrant meiotic recombination in chromosome 21, most likely in the region D21S1/S11-D21S16 which is linked to early onset familial AD. Based on the same rationale, different patterns of meiotic recombination in the nondisjunct chromosome 21 within DS patients grouped according to the concomitant disease are predicted.
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Affiliation(s)
- A Petronis
- Neurogenetics Section, Centre for Addiction and Mental Health, Clarke Division, 250 College Street, Toronto, Ontario, M5T 1R8, Canada.
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Salomão Schwartzman J, Zatz M, dos Reis Vasquez L, Ribeiro Gomes R, Koiffmann CP, Fridman C, Guimarães Otto P. Rett syndrome in a boy with a 47,XXY karyotype. Am J Hum Genet 1999; 64:1781-5. [PMID: 10330367 PMCID: PMC1377923 DOI: 10.1086/302424] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Baumgartner A, Van Hummelen P, Lowe XR, Adler ID, Wyrobek AJ. Numerical and structural chromosomal abnormalities detected in human sperm with a combination of multicolor FISH assays. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1999; 33:49-58. [PMID: 10037323 DOI: 10.1002/(sici)1098-2280(1999)33:1<49::aid-em6>3.0.co;2-f] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A pair of multicolor FISH assays (X-Y-21 and A-M-16) was developed for human sperm to simultaneously measure sex ratios; aneuploidies involving chromosomes 1, 16, 21, X, and Y; meiotic diploidies; and structural aberrations involving chromosome 1p. Sex ratios in sperm were not significantly different from unity among healthy men. Baseline frequencies of disomic sperm for chromosomes 1, 8, and 21 were similar (6.7 per 10(4) sperm, 95% CI of 5.6-8.1), suggesting that among these three chromosomes, chromosome 21 was not especially prone to nondisjunction. Frequencies of disomy 16 sperm were significantly lower, however (3.5 per 10(4) sperm, 95% CI of 2.0-6.2; P < 0.02). The baseline frequencies of sperm disomy by FISH for chromosomes 16 and 21 were validated against aneuploidy data obtained by the hamster-egg technique for human sperm cytogenetics. The frequencies of X-X, Y-Y, X-Y ("Klinefelter") sperm and sex-null ("Turner") sperm were 5.5, 5.1, 5.5, and 7.8 per 10(4) sperm, respectively. For chromosomes 16 and 21, the frequencies of nullisomic and disomic sperm were similar, suggesting that gain and loss events occurred symmetrically. However, more gain than loss was reported for chromosomes 1, X, and Y. The frequency of MI and MII diploid sperm (with flagella) was approximately 12 per 10(4) (range 8.3-16.7 per 10(4) sperm). Based on flagella data, the frequency of somatic cells in the semen was estimated to be approximately 1.8 per 10(4) sperm. Loss or gain of a portion of chromosome-arm 1p occurred in 5.5 per 10(4) sperm, and the percentage of sperm carrying structural aberrations within the haploid genome as calculated from FISH (1.4%), was similar to that obtained with the hamster-egg technique. These complementary sperm FISH assays have promising applications in studies of chromosomally abnormal sperm after exposure to occupational, medical, and environmental toxicants.
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Affiliation(s)
- A Baumgartner
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, California 94550, USA
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43
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Abstract
OBJECTIVES Correlations between parental age, aneuploidy in germ cells and recent findings on aetiological factors in mammalian trisomy formation are reviewed. METHODS Data from observations in human oocytes, molecular studies on the origin of extra chromosomes in trisomies, experiments in a mouse model system, and transgenic approaches are shown. RESULTS Errors in chromosome segregation are most frequent in meiosis I of oogenesis in mammals and predominantly predispose specific chromosomes and susceptible chiasmate configurations to maternal age-related nondisjunction. Studies on spindle structure, cell cycle and chromosome behaviour in oocytes of the CBA/Ca mouse used as a model for the maternal age-effect suggest that hormonal homeostasis and size of the follicle pool influence the quality, maturation competence and spindle size of the mammalian oocyte. Predisposition to errors in chromosome segregation are critically dependent on altered cell cycles. Compromised protein synthesis and mitochondrial function affect maturation kinetics and spindle formation, and cause untimely segregation of chromosomes (predivision), mimicking an aged phenotype. CONCLUSIONS Altered cell cycles and untimely resolution of chiasmata but also nondisjunction of late segregating homologues caused by asynchrony in cytoplasmic and nuclear maturation appear to be causal to errors in chromosome segregation with advanced maternal age. Oocytes appear to lack checkpoints guarding against untimely chromosome segregation. Genes and exposures affecting pool size, hormonal homeostasis and interactions between oocytes and their somatic compartment and thus quality of follicles and oocytes have the potential to critically influence chromosome distribution in female meiosis and affect fertility in humans and other mammals.
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Yenamandra A, Zhou X, Trinchitella L, Susin M, Sastry S, Mehta L. Renal cell carcinoma with X;1 translocation in a child with Klinefelter syndrome. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1096-8628(19980526)77:4<281::aid-ajmg6>3.0.co;2-q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
The following questions are addressed: (A) What are aneuploidogens and how do they act? (B) Is there any evidence that aneuploidy per se causes malformations? (C) What examples are there of abnormalities, apparently attributable to aneuploidogens acting as teratogens? (D) Do abnormalities of cell division cause both teratogenesis and aneuploidy? Considerable research has addressed question (A), but there is little which addresses the other three questions. The question of whether aneuploidy per se causes malformations remains open. Some suggestions for further research are made.
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Affiliation(s)
- J H Ford
- Genetic Consulting and Testing (G.C.A.T) Pty Ltd., Port Adelaide, Australia.
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Abstract
Constitutional chromosomal abnormalities are an important cause of miscarriage, infertility, congenital anomalies and mental retardation in humans. Most human constitutional chromosomal imbalance results from aneuploidy, a condition that appears to be much more frequent in humans than in any other species studied. Chromosomal rearrangements and segmental deletions and duplications also occur in humans, but much less often. Although treatment of human somatic cells with some environmental agents produces chromosomal damage, no measurable increase in the frequency of constitutional chromosomal abnormalities has been unequivocally demonstrated among the children of parents exposed to any agent. Recent work has provided insight into a variety of mechanisms by which chromosomal abnormalities can arise during gametogenesis and early embryogenesis. Mechanisms have also been recognized that can correct or partially compensate for chromosomal imbalance, sometimes permitting survival of conceptuses that would otherwise be lost early in gestation. This improved understanding can be used to refine future studies of the cytogenetic effects of environmental exposures.
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Affiliation(s)
- D E McFadden
- Department of Pathology, B.C. Children's Hospital, Canada.
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Eichenlaub-Ritter U. Parental age-related aneuploidy in human germ cells and offspring: a story of past and present. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1996; 28:211-236. [PMID: 8908181 DOI: 10.1002/(sici)1098-2280(1996)28:3<211::aid-em6>3.0.co;2-g] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Parental age is the most important aetiological factor in trisomy formation in humans. Cytogenetic studies on germ cells reviewed here imply that (i) 2-4% sperm are aneuploid and 8.6% oocytes from IVF are hyperploid (ii) a paternal age effect may exist, and (iii) oocytes of aged women contain precociously separated chromatids in metaphase II. Trisomy data suggest that most aneuploidy is generated during meiosis I of oogenesis and is maternal age-dependent. Trisomy 18 is unique, originating mostly from maternal meiosis II errors. The extra gonosome in 47, XXY derives mostly from a paternal meiosis I error. Trisomy of individual chromosomes may remain low, linearly rise, or exponentially increase with advanced maternal age. Maternal age related trisomies involve achiasmatic and normochiasmate chromosomes, and chromosomes with disturbed recombination and distally located chiasmata. Hypotheses on the origin of the maternal age effect are critically reviewed. One model is presented that relates to altered cell cycle and protein phosphorylation in oocytes of aged mammals and accounts for most of the observed data in humans and in experimental studies. Aneuploidy may thus involve a predetermined component but is possibly also influenced by extrinsic factors reducing oocyte quality or depleting the oocyte pool precociously. Areas of future research are proposed to elucidate (i) the significance of early disturbances in the prenatal ovary, (ii) parameters diminishing the quality of oocytes in dictyate stage, and (iii) mechanisms enabling oocytes to process all chromosomal configurations successfully during later stages of oogenesis. Studies with newly developed and existing animal models appear indispensable to identify exposures affecting chromosome disjunction during meiosis, especially in the aging female.
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Abstract
Aneuploidy, the presence of an extra or missing chromosome, is the most frequent cause of mental retardation and pregnancy loss in our species. Studies can be divided into those of incidence, origin, and etiology. Trisomy 21 is the most common aneuploidy among liveborns whereas monosomy X and trisomy 16 are the most frequent causes of pregnancy loss. Aneuploidy primarily arises by the process of nondisjunction in the first meiotic division of maternal meiosis; however, this varies among chromosomes in that some show a significant proportion of paternal and/or meiosis II errors. The most common etiological factor associated with aneuploidy is advancing maternal age and it is generally agreed that this is a result of the increasing likelihood of nondisjunction in the aging ovary. There has been intense debate as to the existence of of a paternal age effect and recent studies on human sperm suggest that there may be a small effect for the sex chromosomes. Furthermore, recent molecular studies on trisomic conceptuses have revealed a second etiological factor associated with nondisjunction, namely, reduced genetic recombination.
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Affiliation(s)
- D K Griffin
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Wyrobek AJ, Aardema M, Eichenlaub-Ritter U, Ferguson L, Marchetti F. Mechanisms and targets involved in maternal and paternal age effects on numerical aneuploidy. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 1996; 28:254-264. [PMID: 8908184 DOI: 10.1002/(sici)1098-2280(1996)28:3<254::aid-em9>3.0.co;2-d] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Trisomy in the human appears to be predominantly associated with maternal age. The maternal-age effect, however, shows considerable variability across affected chromosomes. Chromosome-specific variation has been reported in the shapes of the maternal-age-effect curves, including very small effects for the large chromosomes (groups A and B), linear increases (chromosome 16), and exponential increases (chromosome 21). There is also variation among chromosomes in whether the segregation errors occur predominantly at maternal meiosis I, meiosis II, and/or postfertilization mitotic divisions. There is also limited epidemiological evidence for a paternal-age effect, which was recently supported by the findings of age-related increases in sperm aneuploidy using fluorescence in situ hybridization methods. The paternal-age effect is considerably smaller than the maternal and is more likely to involve meiotic II errors of the sex chromosomes, whereas the maternal-age effect is more likely to arise from meiotic I errors producing autosomal trisomies. These and other differences suggest that constitutional aneuploidy arises by multiple mechanisms that may affect (1) the nature and timing of an initiating lesion affecting the oocyte or sperm; (2) the cellular physiology of the time of the nondisjunction event at meiosis I, II, or postfertilization; and (3) the selection against specific chromosomal aneuploidies during embryonic development. Multidisciplinary research is needed to understand the maternal and paternal-age effects on aneuploidy, to (1) identify and characterize the genes that control meiosis, recombination, and segregation; (2) identify the micro-environmental factors around the oocyte and mole germ cells that are involved in the age effects; (3) develop a laboratory animal model for the age effects; (4) characterize the role of genetics, physiology, and environmental toxicology for the paternal-age effects; and (5) identify cohorts of men and women of differing ages who have been exposed to high doses of candidate aneugens and conduct epidemiological investigations of aneuploidies transmitted to their offspring.
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Affiliation(s)
- A J Wyrobek
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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