Deletion of the short arm of chromosome No. 10

Clinical report of a neonate carrying a large deletion in the 10p15.3p13 region and review of the literature

Background

Terminal deletion of chromosome 10p is a rare chromosomal abnormality. We report a neonatal case with a large deletion of 10p15.3p13 diagnosed early because of severe clinical manifestations.

Case presentation

Our patient presented with specific facial features, hypoparathyroidism, sen sorineural deafness, renal abnormalities, and developmental retardation, and carried a 12.6 Mb deletion in the 10p15.3 p13 region. The terminal 10p deletion involved in our patient is the second largest reported terminal deletion reported to date, and includes the ZMYND11 and GATA3 genes and a partial critical region of the DiGeorge syndrome 2 gene (DGS2).

Conclusion

On the basis of a literature review, this terminal 10p deletion in the present case is responsible for a specific contiguous gene syndrome. This rare case may help the understanding of the genotype–phenotype spectrum of terminal deletion of chromosome 10p.

Barakat syndrome revisited

Barakat syndrome also known as HDR syndrome (Online Mendelian Inheritance in Man [OMIM] 146255), was first described by Barakat et al. in . It is a rare genetic disorder characterized by the triad of hypoparathyroidism "H," sensorineural deafness "D," and renal disease "R." The defect is caused by deletions in chromosome 10p14 or mutations in the GATA3 gene. Although the syndrome has been phenotypically defined by this triad the literature identifies cases with different components with, or without GATA3 defects making the definition of the syndrome confusing. We analyzed 180 cases and attempted to define the phenotype of the syndrome and suggest guidelines for diagnosis. We suggest that the diagnosis could be confirmed in patients who have all three components, and in those who have two components with a positive family history. GATA3 testing is optional to establish the diagnosis in these patients. The syndrome should be considered in patients with isolated "D" where other causes of "D" have been excluded and those with isolated "R," especially if there is family history of any of these components. In these instances, confirmatory GATA3 testing is indicated to confirm the diagnosis. In patients with nonsurgical "H," where "D" and "R" have been conclusively ruled out GATA3 studies are not needed as none of these patients were shown to be GATA3 haploinsufficient. Only 64.4% of patients in our review had "HDR." Some findings might have not been recognized or may could have appeared later in life, but it is evident that this syndrome is genotypically heterogeneous.

Unexplained antepartum stillbirth: a consequence of placental aging?

Unexplained antepartum stillbirth is a major obstetric health problem. Data demonstrate a rapid rise in risk per 1000 continuing pregnancies as gestation advances beyond 40 weeks. We review the evidence that such stillbirths are a consequence of aging related changes in the late gestation placenta. We suggest that the relatively small number of continuing pregnancies after 40 completed weeks means that negative effects of genes that produce aging affect so few pregnancies that polymorphisms in genes that produce these effects are retained in the population. Aging related changes likely represent a consequence of the damaging effects of oxidative stress, increased by cigarette smoking counteracted by the mitigating effects of oxidative defence pathways. The aging related changes are likely downstream from nutrient sensing units such as mTOR and include effects on production of telomerase and consequent shortening of telomere length. The late gestation changes occur in the context of increasing fetal growth and nutrient supply demands that can produce the rapid development of a mismatch between placental supply and fetal need resulting in fetal demise. Premature aging may also play an important role in antepartum stillbirth occurring earlier in pregnancy, especially in the context of growth restriction.

Infantile hypertrophic pyloric stenosis--genetics and syndromes

Infantile hypertrophic pyloric stenosis (IHPS) is a common condition in neonates that is characterized by an acquired narrowing of the pylorus. The aetiology of isolated IHPS is still largely unknown. Classic genetic studies have demonstrated an increased risk in families of affected infants. Several genetic studies in groups of individuals with isolated IHPS have identified chromosomal regions linked to the condition; however, these associations could usually not be confirmed in subsequent cohorts, suggesting considerable genetic heterogeneity. IHPS is associated with many clinical syndromes that have known causative mutations. Patients with syndromes associated with IHPS can be considered as having an extreme phenotype of IHPS and studying these patients will be instrumental in finding causes of isolated IHPS. Possible pathways in syndromic IHPS include: (neuro)muscular disorders; connective tissue disorders; metabolic disorders; intracellular signalling pathway disturbances; intercellular communication disturbances; ciliopathies; DNA-repair disturbances; transcription regulation disorders; MAPK-pathway disturbances; lymphatic abnormalities; and environmental factors. Future research should focus on linkage analysis and next-generation molecular techniques in well-defined families with multiple affected members. Studies will have an increased chance of success if detailed phenotyping is applied and if knowledge about the various possible causative pathways is used in evaluating results.

Interstitial deletion of 10p and atrial septal defect in DiGeorge 2 syndrome

We present molecular genetic investigations of a 4-year-old boy with craniofacial dysmorphism and developmental delay. Trivial mitral and tricuspid regurgitation without gross structural abnormality was diagnosed by echocardiography. High-resolution chromosome analysis revealed an interstitial deletion, del(10)(p12.1p12.32). To characterize the deletion size and breakpoints, we performed fluorescence in situ hybridization analysis using 27 BAC clones. Our data demonstrate an approximately 5.5 Mb deletion del(10)(p12.1p12.31). Surprisingly, the BAC clone RP11-56H7 that contains NEBL, an apparent downstream gene of the cardiogenic transcription factor HAND2 previously shown to be deleted in the patients with DiGeorge 2 syndrome and 10p13 deletion, was deleted in our patient with 10p12.1-p12.31 deletion. In addition, we provide clinical data and results of molecular analysis for a patient with multiple congenital anomalies including Ebstein's anomaly, kidney malformations, and 10p13-p14 deletion. We also reviewed 19 patients with congenital heart defects and deletions involving 10p and propose that atrial septal defect (ASD) is a common cardiac anomaly associated with DiGeorge 2 syndrome. Based on genotype-phenotype analysis of published patients and those reported herein, we propose an approximately 1.0 Mb critical region between loci D10S547 and D10S2176 in 10p14 to be associated with ASD. Considering that septal defects are the most frequent congenital heart anomaly, we suggest that further investigations in the 10p critical region are important to identify gene(s) responsible for this common birth defect.

MRI findings in a patient with partial monosomy 10p

Partial monosomy 10p is a rare chromosomal disorder characterised by frontal bossing, micrognathia, congenital heart defects, vesicoureteral abnormalities, and developmental delay. This is the first report to describe seizures not associated with hypocalcaemia, as well as cortical atrophy and decreased white matter volume on magnetic resonance imaging, in a patient with documented partial monosomy 10p. The neuroradiographic abnormalities found in this patient provide a first step towards understanding the aetiology of the developmental delay and ventriculomegaly associated with this chromosomal abnormality.

HDR syndrome (hypoparathyroidism, sensorineural deafness, renal dysplasia) associated with del(10)(p13)

A combination of hypoparathyroidism, sensorineural deafness, and renal dysplasia has been considered to be a new syndrome inherited in an autosomal dominant fashion; we name the condition "HDR syndrome." We describe a Japanese girl who has HDR syndrome associated with de novo del(10)(p13). The chromosome deletion suggests that the putative gene(s) responsible for HDR syndrome is located at a 10pter-->p13 region.

Velo-cardio-facial and partial DiGeorge phenotype in a child with interstitial deletion at 10p13--implications for cytogenetics and molecular biology

We report on a female with a interstitial deletion of 10p13 and a phenotype similar to that seen with the 22q deletion syndromes (DiGeorge/velo-cardio-facial). She had a posterior cleft palate, perimembranous ventricular septal defect, dyscoordinate swallowing, T-cell subset abnormalities, small ears, maxillary and mandibular hypoplasia, broad nasal bridge, deficient alae nasi, contractures of fingers and developmental delay. This could indicate homology of some developmental genes at 22q and 10p so that patients with the velocardiofacial phenotype who do not prove to be deleted on 22q are candidates for a 10p deletion.

Family with partial monosomy 10p and trisomy 10p

We report on a family with an abnormality of 10p. The propositus has monosomy for the distal region of 10p and severe psychomotor delay, growth failure, congenital heart defect, multicystic kidney, grade V vesicoureteric reflux, and neurosensory hearing loss. The mother and the elder brother of the propositus carry a balanced reciprocal translocation (5q;10p)(q35.3;p12.3). A retarded and epileptic maternal aunt was found to have dup(10p). Study of the family history led to the successful obstetric management of a subsequent twin pregnancy in which an affected fetus with dup(10p) was identified and selectively terminated, while the other normal twin was delivered at term without problems.

Deletion of the short arm of chromosome 10 (10p13): report of a patient and review

Since the first description by Elliot et al. [1970, Am J Dis Child 119:72-73] of a probable partial deletion of chromosome 10p, 17 other cases have been reported. The phenotypic expression is variable, but the craniofacial malformations constitute a more consistent finding. The 10p deletion syndrome has been associated with the DiGeorge anomaly in several patients. We report on an additional case of 10p deletion syndrome and review the literature.

Segregation of three reciprocal translocations in the same family: t(3;4), t(5;10), and t(15;21)

A male infant with static antenatal encephalopathy and epilepsy was found to have a duplication of 5p12----5pter and deficiency of 10p13----10pter. Each of his parents was a carrier of a balanced reciprocal translocation. A third translocation was found in the maternal grandfather. The pedigree of each translocation and the segregation of parental reciprocal translocations are discussed.

Renal and urinary tract abnormalities associated with chromosome aberrations

The frequency of malformations of the kidney and urinary tract is much higher in patients with chromosome aberrations than in the general population. Sixty to 100% of "cat-eye" syndrome, 60 to 80% of Turner, 75% of trisomy 8, 33 to 70% of trisomy 18, 50 to 60% of trisomy 13, and over 50% of triploidy and tetraploidy patients may have such abnormalities. Renal and urinary tract malformations should be looked for in all patients with chromosome aberrations. Moreover, a chromosome study is indicated in any fetus with an ultrasonographic evidence of urinary tract abnormality.

Partial monosomy of chromosome 10 short arms

Two children with monosomy 10p13 are reported. In the first case the monosomy was the result of a maternal balanced translocation t(3;10) (p27;p13) while the second case was a de novo mutation. We reviewed clinical details of cases reported so far and found that certain symptoms are typical of the deletion of a comparatively large segment of chromosome 10 short arms. These symptoms include mental and growth retardation, skull abnormalities, antimongoloid slant of the eyes, ear abnormalities, anteverted nostrils, abnormalities of the hands and feet, cryptorchidism in boys, and, primarily, hypoplasia or aplasia of the olfactory bulbs and olfactory tracts as well as narrow palpebral fissures or eyelid ptosis.

Two chromosomal syndromes in the same family: monosomy and trisomy for part of the short arm of chromosome 10

A grandfather with balanced translocation t(1:10) gave rise to three possible combinations involving chromosome 10: balanced translocation and trisomy for part of the short arm 10p13 leads to pter in the second generation, and mono- and trisomy 10p13 leads to pter in the third generation. The clinical signs and symptoms of the present case with monosomy 10p13 leads to pter are compared with those of 9 earlier reported cases with a deleted 10p. Together they represent a clinically recognizable syndrome with antimongoloid eye slant, ptosis, epicanthus, high arched or cleft palate, flat nasal bridge, micrognathia, small round and low-set ears, wide spaced nipples, cardiac and urinary tract abnormalities, hand and foot anomalies, hypoplasia/absence of the olfactory bulbs/tracts, psychomotor and growth retardation. More than 20 cases of the trisomy 10p syndrome have been described earlier. The most constant clinical findings are mental retardation, dolichocephaly, frontal bossing, broad nasal bridge, cheilo-palatoschisis, retrognathia and variable internal malformations. We found, however, the clinical characteristics in this syndrome more variable than for the monosomy 10p13 leads to pter syndrome. Our two cases, representing the eldest and the youngest described, have rather few of the typical characteristics, and few in common with each other. This indicates the difficulty in making this diagnosis on clinical features only without a cytogenetic verification.

Partial monosomy 10p syndrome

A 7 year-old girl is described with a de novo deletion of the short arm of chromosome 10 (qter p13:). The clinical features of: mental retardation, a large asymmetric head, antimongoloid slant, exophthalmos, epicanthus, ptosis, abnormal ears, pectus excavatum and widely spaced nipples are compared with those of five earlier reported cases with a deletion 10p. The data available suggest the existence of a clinically recognizable monosomy 10p syndrome.

Clinicopathological conference: a newborn monozygotic twin with abnormal facial appearance and respiratory insufficiency

The second of twins males expired of respiratory insufficiency shortly after birth. Unusual facial appearance included prominent forehead, flat nasal bridge, widely separated inner canthi, downward slanting eyes with narrow palpebral fissures, epicanthic folds, small mouth and micrognathia, and apparently low-set ears; there was also cryptorchidism bilaterally and a simian crease bilaterally. The pregnancy of the 19-year-old black woman was not unusual, but polyhydramnios accompanied the delivery of this twin. The twin placentae were diamniotic and monochorionic, one being slightly immature with a two-vessel cord. We interpreted the karyotype as 46,XY,del(10) (p11-15): The brother and parents were normal. The dysmorphic features of this and three previously reported cases of 10p- do not permit definition of a syndrome. These are apparently the first monozygous twins presenting discordance of chromosomal structure; previously reported chromosomal discordance in monozygous twins involved numerical abnormality. Considering that the mechanism monozygous twinning is not understood, we note that the occurrence of both twinning and a structural aberration in one of the twins suggests the possibility of a common cause.

Phenotype associated with ring 10 chromosome: report of patient and review of literature

A 15-month-old infant's peripheral blood chromosome analysis showed the following defects: 46,XY,r(10)(p15.3q26.1) in 84 cells, 45,XY,-r(10) in 13 cells, and 47,XY,r(10),+r(10) in one cell. Clinical abnormalities included growth retardation, microcephaly, prominent nasal bridge, macular hypoplasia, persistent pulmonary hypertension, and posterior urethral valves with hydronephrosis. Comparison of the phenotype of five other patients with a ring chromosome 10 with the present case showed the following common manifestations: growth retardation, microcephaly, undescended testes, hydronephrosis, and, in males, posterior urethral valves. To date, this last anomaly has not been seen in patients with either a del(10p) or a del(10q) abnormality.

10p- syndrome associated with multiple chromosomal abnormalities

A karyotype with six de novo autosomal abnormalities in chromosomes 2,4,9,10,12, and 13 was identified in a 7-year-old boy with mental retardation and other minor malformations. The G- and C-banding techniques revealed an equilibrated translocation between autosomes 2 and 4 and between autosomes 9 and 13. One chromosome 10 has lost genetic material from its short arms, probably because of an interstitial deletion. An unidentified chromosomal fragment has become inserted in the long arms of an autosome 12. The G bands demonstrate that genetic material inserted in the autosome 12 is not the genetic material deleted from the autosome 10. The propositus presents clinical features similar to the reported cases with 10p- syndrome. Nevertheless it is not possible to establish the influence of the genetic material inserted in autosome 12 on the propositus' phenotype.

Chromosomes and the gynecologist

Recent advances in cytogenetic techniques made a valuable contribution toward the modern practice of obstetrics and gynecology. The state of the art regarding the application of these techniques is reviewed in the following areas: the clinical features related to the various sex and autosomal chromosomal anomalies, the cytogenetics of gynecologic malignancies, the chromosomal analysis of spontaneous abortion and of parents with habitual abortions. Chromosome studies in male infertility revealed abnormalities in 11.5 per cent of 69 patients with azoospermia and 9.1 per cent of 165 patients with oligospermia. Among 77 patients with primary amenorrhea, 27.3 per cent revealed chromosomal abnormalities compared to 3.8 per cent in 103 patients with secondary amenorrhea. The term "ovotesticular dysgenesis" is used for the first time in the literature to describe a specific histologic type of streak gonad which contains ovarian stroma and dysgenetic testicular tubules.

New chromosomal dysmorphic syndromes. 2. Trisomy 10p

This is the report of a family in which a balanced translocation in the mother t(5;10)(p15;p13) led to an unbalanced chromosomal constitution in two children. It was identified by G-banding analysis as trisomy of the distal portion of the short arm of chromosome 10 (p13 leads to pter). Comparison with 15 previous reports of trisomy 10p confirms the existence of a characteristic dysmorphic syndrome.

The human complement after trypsin pretreatment as compared to the Paris standard

A composite G-banding diagram after trypsin pretreatment of metaphase chromosomes from 5 different individuals (2 males and 3 females) is presented and compared with the Paris diagram. The patterns obtained by the present technique were very similar to those previously reported. It was found that the darkly staining bands were much more consistent in appearance than the lightly staining bands and that there was little individual variation.