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Wei S, Li Y, Yang W, Chen S, Liu F, Zhang M, Ban B, He D. Functional investigation of a novel ANKRD11 frameshift variant identified in a Chinese family with KBG syndrome. Heliyon 2024; 10:e28082. [PMID: 38515699 PMCID: PMC10956060 DOI: 10.1016/j.heliyon.2024.e28082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 03/11/2024] [Accepted: 03/12/2024] [Indexed: 03/23/2024] Open
Abstract
KBG syndrome is a rare autosomal dominant condition characterized by multisystem developmental disorder, primarily caused by loss-of-function variants in ankyrin repeat domain-containing protein 11 (ANKRD11). Approximately 80 % of ANKRD11 variants associated with KBG syndrome, are frameshift and nonsense variants. Current insight into the pathogenesis of KBG syndrome resulting from ANKRD11 truncating variants remains limited. Here, we presented two members from a non-consanguineous Chinese pedigree both exhibiting characteristics fitting the KBG syndrome-associated phenotypic spectrum. Whole-exome sequencing identified a novel heterozygous frameshift variant in ANKRD11 (NM_013275.6, c.2280_2281delGT, p.Y761Qfs*20) in the proband. Sanger sequencing confirmed that the variant was inherited from her mother and co-segregated with KBG syndrome phenotype. In vitro functional assays revealed that the frameshift variant escaped nonsense-mediated mRNA decay, and resulting in a truncated protein with significantly increased expression levels compared to full-length ANKRD11. Immunofluorescence results demonstrated that truncated protein was predominantly expressed in the nucleus of HEK293 cells, while wild-type ANKRD11 was equally distributed in both the nucleus and cytoplasm. Moreover, the truncated protein significantly reduced CDKN1A/P21-promoter luciferase activity in comparison to wild-type ANKRD11 protein, as well as a remarkably decrease in the endogenous CDKN1A/P21 mRNA level in HEK293 cells. These findings suggest a loss of transcriptional activation function and potentially a dominant-negative mechanism. Overall, our study expands the mutational spectrum of ANKRD11 gene and provides new insights into the pathogenic mechanism of KBG syndrome caused by ANKRD11 truncating variants.
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Affiliation(s)
- Shuoshuo Wei
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Medical Research Center, Affiliated Hospital of Jining Medical University, Jining, PR China
| | - Yanying Li
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Chinese Research Center for Behavior Medicine in Growth and Development, Jining, PR China
| | - Wanling Yang
- Department of Paediatrics and Adolescent Medicine, The University of Hong Kong, PR China
| | - Shuxiong Chen
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Medical Research Center, Affiliated Hospital of Jining Medical University, Jining, PR China
| | - Fupeng Liu
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Medical Research Center, Affiliated Hospital of Jining Medical University, Jining, PR China
| | - Mei Zhang
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Chinese Research Center for Behavior Medicine in Growth and Development, Jining, PR China
| | - Bo Ban
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Medical Research Center, Affiliated Hospital of Jining Medical University, Jining, PR China
- Chinese Research Center for Behavior Medicine in Growth and Development, Jining, PR China
| | - Dongye He
- Department of Endocrinology, Genetics and Metabolism, Affiliated Hospital of Jining Medical University, Jining, PR China
- Medical Research Center, Affiliated Hospital of Jining Medical University, Jining, PR China
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Donnellan EP, Gorman KM, Shahwan A, Allen NM. Epileptic dyskinetic encephalopathy in KBG syndrome: Expansion of the phenotype. Epilepsy Behav Rep 2024; 25:100647. [PMID: 38317675 PMCID: PMC10839861 DOI: 10.1016/j.ebr.2024.100647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 01/15/2024] [Accepted: 01/15/2024] [Indexed: 02/07/2024] Open
Abstract
KBG syndrome is characterised by developmental delay, dental (macrodontia of upper central incisors), craniofacial and skeletal anomalies. Since the identification of variants in the gene (ANKRD11) responsible for KBG syndrome, wider phenotypes are emerging. While there is phenotypic variability within many features of KBG syndrome, epilepsy is not usually markedly severe and movement disorders largely undocumented. Here we describe a novel early onset phenotype of dyskinetic epileptic encephalopathy in a male, who presented during infancy with a florid hyperkinetic movement disorder and developmental regression. Initially he had epileptic spasms and tonic seizures, and EEGs revealed a modified hypsarrhythmia. The epilepsy phenotype evolved to Lennox-Gastaut syndrome with seizures resistant to multiple anti-seizure therapies and the movement disorder evolved to choreoathetosis of limbs and head with oro-lingual dyskinesias. Previous extensive neurometabolic and imaging investigations, including panel-based exome sequencing were unremarkable. Later trio exome sequencing identified a de novo pathogenic heterozygous frameshift deletion of ANKRD11 (c.6792delC; p.Ala2265Profs*72). Review of the literature did not identify any individuals with such a hyperkinetic movement disorder presentation in combination with early-onset epileptic encephalopathy. This report expands the phenotype of ANKRD11-related KBG syndrome to include epileptic dyskinetic encephalopathy.
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Affiliation(s)
- Eoin P. Donnellan
- Dept. of Paediatrics, Galway University Hospital, Ireland
- Dept. of Paediatrics, School of Medicine, University of Galway, Ireland
| | - Kathleen M. Gorman
- Dept of Paediatric Neurology and Neurophysiology, Children’s Health Ireland at Temple St., Dublin 1, Ireland
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Amre Shahwan
- Dept of Paediatric Neurology and Neurophysiology, Children’s Health Ireland at Temple St., Dublin 1, Ireland
- School of Medicine, Royal College of Surgeons in Ireland, Ireland
| | - Nicholas M. Allen
- Dept. of Paediatrics, Galway University Hospital, Ireland
- Dept. of Paediatrics, School of Medicine, University of Galway, Ireland
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Choi Y, Choi J, Do H, Hwang S, Seo GH, Choi IH, Keum C, Choi JH, Kang M, Kim GH, Yoo HW, Lee BH. KBG syndrome: Clinical features and molecular findings in seven unrelated Korean families with a review of the literature. Mol Genet Genomic Med 2022; 11:e2127. [PMID: 36564961 PMCID: PMC10094073 DOI: 10.1002/mgg3.2127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 11/27/2022] [Accepted: 12/15/2022] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND KBG syndrome is a rare genetic disorder involving macrodontia of the upper central incisors, craniofacial, skeletal, and neurologic symptoms, caused either by a heterozygous variant in ANKRD11 or deletion of 16q24.3, including ANKRD11. Diagnostic criteria were proposed in 2007 based on 50 cases, but KBG syndrome remains underdiagnosed. METHODS Whole exome sequencing (WES) and array comparative genomic hybridization (array CGH) were conducted for genetic analysis and patient phenotypes were characterized based on medical records. RESULTS Eight patients from seven unrelated families were confirmed with KBG syndrome. All patients (8/8, 100%) had some degree of craniofacial dysmorphism and developmental delay or intellectual disabilities. Triangular face, synophrys, anteverted nostril, prominent ears, long philtrum, and tented upper lip, which are typical facial dysmorphism findings in patients with KBG syndrome, were uniformly identified in the eight patients participating in this study, with co-occurrence rates of 4/8 (50%), 4/8 (50%), 4/8 (50%), 4/8 (50%), 5/8 (62.5%), and 5/8 (62.5%), respectively. Various clinical manifestations not included in the diagnostic criteria were observed. Six patients had point mutations in ANKRD11, one had an exonic deletion of ANKRD11, and one had a 16q24.3 microdeletion. According to the ACMG guidelines, all mutations were classified as pathogenic. The c.2454dup (p.Asn819fs*1) mutation in Pt 4 was reported previously. The remaining variants (c.397 + 1G>A, c.226 + 1G>A, c.2647del (p.Glu883Argfs*94), and c.4093C>T (p.Arg1365Ter)) were novel. CONCLUSION The clinical and molecular features of eight patients from seven unrelated Korean families with KBG syndrome described here will assist physicians in understanding this rare genetic condition.
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Affiliation(s)
- Yunha Choi
- Department of Pediatrics, CHA Bundang Medical Center, CHA University, Seongnam, South Korea
| | - Jungmin Choi
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Hyosang Do
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Soojin Hwang
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | | | - In Hee Choi
- Department of Genetic Counseling, University of Ulsan College of Medicine, Seoul, South Korea
| | | | - Jin-Ho Choi
- Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
| | - Minji Kang
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Gu-Hwan Kim
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Han-Wook Yoo
- Department of Pediatrics, CHA Bundang Medical Center, CHA University, Seongnam, South Korea
| | - Beom Hee Lee
- Medical Genetics Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Department of Pediatrics, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea
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Gao F, Zhao X, Cao B, Fan X, Li X, Li L, Sui S, Su Z, Gong C. Genetic and Phenotypic Spectrum of KBG Syndrome: A Report of 13 New Chinese Cases and a Review of the Literature. J Pers Med 2022; 12:jpm12030407. [PMID: 35330407 PMCID: PMC8948816 DOI: 10.3390/jpm12030407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/16/2022] [Accepted: 02/24/2022] [Indexed: 02/06/2023] Open
Abstract
KBG syndrome (KBGS) is a rare autosomal dominant inherited disease that involves multiple systems and is associated with variations in the ankyrin repeat domain 11 (ANKRD11) gene. We report the clinical and genetic data for 13 Chinese KBGS patients diagnosed by genetic testing and retrospectively analyse the genotypes and phenotypes of previously reported KBGS patients. The 13 patients in this study had heterozygous variations in the ANKRD11 gene, including seven frameshift variations, three nonsense variations, and three missense variations. They carried 11 variation sites, of which eight were previously unreported. The clinical phenotype analysis of these 13 patients and 240 previously reported patients showed that the occurrence rates of craniofacial anomalies, dental anomalies, global developmental delays, intellectual disability/learning difficulties, limb anomalies, and behavioural anomalies were >70%. The occurrence rates of short stature, delayed bone age, and spinal vertebral body anomalies were >50%. The frequency of global developmental delays and intellectual disability/learning difficulties in patients with truncated ANKRD11 gene variation was higher than that in patients with missense variation in the ANKRD11 gene (p < 0.05). Collectively, this study reported the genotypic and phenotypic characteristics of the largest sample of KBGS patients from China and discovered eight new ANKRD11 gene variations, which enriched the variation spectrum of the ANKRD11 gene. Variation in the ANKRD11 gene mainly caused craniofacial anomalies, growth and developmental anomalies, skeletal system anomalies, and nervous system anomalies. Truncated variation in the ANKRD11 gene is more likely to lead to global growth retardation and intellectual disability/learning difficulties than missense variation in ANKRD11.
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Affiliation(s)
- Fenqi Gao
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
| | - Xiu Zhao
- Department of Endocrinology, Shenzhen Children’s Hospital, Shenzhen 518000, China;
| | - Bingyan Cao
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
| | - Xin Fan
- Pediatric Dapartment, The Second Affiliated Hospital of Guangxi Medical University, Nanning 510000, China;
| | - Xiaoqiao Li
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
| | - Lele Li
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
| | - Shengbin Sui
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
| | - Zhe Su
- Department of Endocrinology, Shenzhen Children’s Hospital, Shenzhen 518000, China;
- Correspondence: (Z.S.); (C.G.)
| | - Chunxiu Gong
- Department of Endocrinology, Genetics, Metabolism and Adolescent Medicine, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China; (F.G.); (B.C.); (X.L.); (L.L.); (S.S.)
- Correspondence: (Z.S.); (C.G.)
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Digilio MC, Calcagni G, Gnazzo M, Versacci P, Dentici ML, Capolino R, Sinibaldi L, Baban A, Putotto C, Alfieri P, Unolt M, Lepri FR, Alesi V, Genovese S, Novelli A, Marino B, Dallapiccola B. Congenital heart defects in molecularly confirmed KBG syndrome patients. Am J Med Genet A 2021; 188:1149-1159. [PMID: 34971082 DOI: 10.1002/ajmg.a.62632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 10/30/2021] [Accepted: 12/11/2021] [Indexed: 11/11/2022]
Abstract
Congenital heart defects (CHDs) are known to occur in 9%-25% of patients with KBG syndrome. In this study we analyzed the prevalence and anatomic types of CHDs in 46 personal patients with KBG syndrome, carrying pathogenetic variants in ANKRD11 or 16q24.3 deletion, and reviewed CHDs in patients with molecular diagnosis of KBG syndrome from the literature. CHD was diagnosed in 15/40 (38%) patients with ANKRD11 variant, and in one patient with 16q24.3 deletion. Left ventricular outflow tract obstructions have been diagnosed in 9/15 (60%), subaortic or muscular ventricular septal defect in 5/15 (33%), dextrocardia in 1/15 (8%). The single patient with 16q24.3 deletion and CHD had complete atrioventricular septal defect (AVSD) with aortic coarctation. Review of KBG patients from the literature and present series showed that septal defects have been diagnosed in 44% (27/61) of the cases, left ventricular tract obstructions in 31% (19/61), AVSD in 18% (11/61). Septal defects have been diagnosed in 78% of total patients with 16q24.3 deletion. Valvar anomalies are frequently diagnosed, prevalently involving the left side of the heart. A distinctive association with AVSD is identifiable and could represent a marker to suggest the diagnosis in younger patients. In conclusion, after precise molecular diagnosis and systematic cardiological screening the prevalence of CHD in KBG syndrome seems to be higher than previously reported in clinical articles. In addition to septal defects, left-sided anomalies and AVSD should be considered. Clinical management of KBG syndrome should include accurate and detailed echocardiogram at time of diagnosis.
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Affiliation(s)
- Maria Cristina Digilio
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Giulio Calcagni
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Maria Gnazzo
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Paolo Versacci
- Pediatric Cardiology Unit, Department of Pediatrics and Urologic Sciences, "La Sapienza" University, Rome, Italy
| | - Maria Lisa Dentici
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Rossella Capolino
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Lorenzo Sinibaldi
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Anwar Baban
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Carolina Putotto
- Pediatric Cardiology Unit, Department of Pediatrics and Urologic Sciences, "La Sapienza" University, Rome, Italy
| | - Paolo Alfieri
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Marta Unolt
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Francesca R Lepri
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Viola Alesi
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Silvia Genovese
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Antonio Novelli
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Bruno Marino
- Pediatric Cardiology Unit, Department of Pediatrics and Urologic Sciences, "La Sapienza" University, Rome, Italy
| | - Bruno Dallapiccola
- Medical Genetics Unit and Medical Genetics and Rare Disease Research Division, Pediatric Cardiology, Medical Genetics Laboratory, Neuropsychiatry, Scientific Rectorate, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
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Kutkowska-Kaźmierczak A, Boczar M, Kalka E, Castañeda J, Klapecki J, Pietrzyk A, Barczyk A, Malinowska O, Landowska A, Gambin T, Kowalczyk K, Wiśniowiecka-Kowalnik B, Smyk M, Dawidziuk M, Niepokój K, Paczkowska M, Szyld P, Lipska-Ziętkiewicz B, Szczałuba K, Kostyk E, Runge A, Rutkowska K, Płoski R, Nowakowska B, Bal J, Obersztyn E, Gos M. Wide Fontanels, Delayed Speech Development and Hoarse Voice as Useful Signs in the Diagnosis of KBG Syndrome: A Clinical Description of 23 Cases with Pathogenic Variants Involving the ANKRD11 Gene or Submicroscopic Chromosomal Rearrangements of 16q24.3. Genes (Basel) 2021; 12:1257. [PMID: 34440431 DOI: 10.3390/genes12081257] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/12/2021] [Accepted: 08/12/2021] [Indexed: 12/28/2022] Open
Abstract
KBG syndrome is a neurodevelopmental autosomal dominant disorder characterized by short stature, macrodontia, developmental delay, behavioral problems, speech delay and delayed closing of fontanels. Most patients with KBG syndrome are found to have a mutation in the ANKRD11 gene or a chromosomal rearrangement involving this gene. We hereby present clinical evaluations of 23 patients aged 4 months to 26 years manifesting clinical features of KBG syndrome. Mutation analysis in the patients was performed using panel or exome sequencing and array CGH. Besides possessing dysmorphic features typical of the KBG syndrome, nearly all patients had psychomotor hyperactivity (86%), 81% had delayed speech, 61% had poor weight gain, 56% had delayed closure of fontanel and 56% had a hoarse voice. Macrodontia and a height range of -1 SDs to -2 SDs were noted in about half of the patients; only two patients presented with short stature below -3 SDs. The fact that wide, delayed closing fontanels were observed in more than half of our patients with KBG syndrome confirms the role of the ANKRD11 gene in skull formation and suture fusion. This clinical feature could be key to the diagnosis of KBG syndrome, especially in young children. Hoarse voice is a previously undescribed phenotype of KBG syndrome and could further reinforce clinical diagnosis.
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Abstract
BACKGROUND Patients with KBG Syndrome due to ANKRD11 mutations and 16q24.3 microdeletions including ANKRD11 were identified. Classical and most frequent phenotypes include various degrees of intelligence disability (ID), short stature (SS), delayed bone age, macrodontia, distinctive facial features and skeletal anomalies. The variable expressivity of KBG syndrome makes it challenging to establish genotype-phenotype correlations, which also affects further studies for this novel syndrome. We aim to report three unrelated patients with KBG syndrome caused by ANKRD11 gene pathological variants and to evaluate potential associations among ANKRD11 gene variant types, the 16q24.3 microdeletion, and the clinical spectrum of KBG syndrome. METHODS The genetic etiology of three unreported KBG patients was identified by whole exome sequencing and confirmed via Sanger sequencing. Literature review was conducted to summarize the phenotype-genotype relationship based on three unreported Chinese cases and 186 reported cases. RESULTS Two pathological variants (c.7407dupC, p.P2530Rfs*61; c.G3046A, p.D1016N) and one reported variant (c.6792dupC, p. P2271Pfs*8) were detected in our patients. Compared with the 16q24.3 microdeletion, patients harboring ANKRD11 gene mutations showed significantly higher frequency of malformations including macrodontia, long philtrum, abnormal eyebrows, widely spaced eyes, anteverted nares, eyelid ptosis, brachydactyly, brachycephaly (P<0.05), and significantly lower risk of congenital heart diseases and frontal bossing (P<0.05). The intellectual disability (ID) was significantly milder among patients carrying truncating variants located between repression domain 1 (RD1) and activation domain (AD) than those carrying mutations disrupting repression domain 2 (RD2) alone and disrupting all functional domain (RD1, AD or RD2) (P<0.05). CONCLUSIONS Novel pathological variants harbored in the ANKRD11 gene contribute to the KBG syndrome variant spectrum. ANKRD11 gene variants disrupting RD1 and RD2 or RD2 alone are more likely to have more severe ID, which warrants different intervention strategies for KBG syndrome.
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Affiliation(s)
- Qiuyue Li
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Chengjun Sun
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Lin Yang
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Wei Lu
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Feihong Luo
- Department of Pediatric Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
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Kim SJ, Yang A, Park JS, Kwon DG, Lee JS, Kwon YS, Lee JE. Two Novel Mutations of ANKRD11 Gene and Wide Clinical Spectrum in KBG Syndrome: Case Reports and Literature Review. Front Genet 2020; 11:579805. [PMID: 33262785 PMCID: PMC7687677 DOI: 10.3389/fgene.2020.579805] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/22/2020] [Indexed: 12/13/2022] Open
Abstract
Background KBG syndrome (OMIM #148050) is a rare, autosomal dominant inherited genetic disorder caused by heterozygous mutations in the ankyrin repeat domain-containing protein 11 (ANKRD11) gene or by microdeletion of chromosome 16q24.3. It is characterized by macrodontia of the upper central incisors, distinctive facial dysmorphism, short stature, vertebral abnormalities, hand anomaly including clinodactyly, and various degrees of developmental delay. KBG syndrome presents with variable clinical feature and severity among individuals. Here, we report two KBG patients who have different novel heterozygous mutations of ANKRD11 gene with wide range of clinical manifestations. Case presentation Two novel heterozygous mutations of ANKRD11 gene were identified in two unrelated Korean patients with variable clinical presentations. The first patient presented with short stature and early puberty and was treated with growth hormone and gonadotropin-releasing hormone agonist without adverse effects. He had mild intellectual disability. In targeted exome sequencing, a novel de novo frameshift variant was identified in ANKRD11, c.5889del, and p. (Ile1963MetfsX9). The second patient had severe intellectual disability with epilepsy. He had normal height and prepubertal stage at the age of 11 years. He had behavioral problems such as autism-like features, anxiety, and stereotypical movements. Whole exome sequencing (WES) was performed, and the novel heterozygous mutation, c3310dup, p. (Glu110GlyfsTer5) in ANKRD11 was identified. Conclusion KBG syndrome is often underdiagnosed because of its non-specific features and phenotypic variability. Performing a next—generation sequencing panel, including the ANKRD11 gene for cases of developmental delay with/without short stature may be helpful to identify hitherto undiagnosed KBG syndrome patients.
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Affiliation(s)
- Su Jin Kim
- Department of Pediatrics, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
| | - Aram Yang
- Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Ji Sun Park
- Department of Pediatrics, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
| | - Dae Gyu Kwon
- Department of Orthopaedic Surgery, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
| | - Jeong-Seop Lee
- Department of Psychiatry, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
| | - Young Se Kwon
- Department of Pediatrics, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
| | - Ji Eun Lee
- Department of Pediatrics, Inha University Hospital, Inha University College of Medicine, Incheon, South Korea
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Sayed ISM, Abdel-Hamid MS, Abdel-Salam GMH. KBG syndrome in two patients from Egypt. Am J Med Genet A 2020; 182:1309-1312. [PMID: 32222090 DOI: 10.1002/ajmg.a.61552] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/19/2020] [Accepted: 03/02/2020] [Indexed: 11/07/2022]
Abstract
KBG syndrome is an intellectual disability (ID) associated with multiple congenital anomalies in which the macrodontia could be the clue for the diagnosis. It is caused either by heterozygous variant in ANKRD11 gene or 16q24.3 microdeletions that involve the ANKRD11 gene. Here, we report on two unrelated male patients who presented with ID, short stature, webbing of neck, and cryptorchidism. Noonan syndrome was suspected first but the presence of macrodontia in both patients pointed to KBG syndrome which was confirmed thereafter by the identification of a novel pathogenic variant in ANKRD11 gene, c.5488G>T (p.E1830*). Macrodontia was noticed in all the deciduous anterior teeth in Patient 1. This observation was reported previously in few patients, but it seems to be a common feature that could be misdiagnosed as premature eruption of teeth. Therefore, our results confirm that maxillary permanent central incisors may not be the only teeth affected in KBG but also all the deciduous teeth. Interestingly, desquamative gingivitis was additionally noted in Patient 1, which has not been reported previously, however; it could be a coincidental finding. To the best of our knowledge, this is the first report from Egypt.
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Affiliation(s)
- Inas S M Sayed
- Orodental Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Mohamed S Abdel-Hamid
- Medical Molecular Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Ghada M H Abdel-Salam
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
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10
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Gnazzo M, Lepri FR, Dentici ML, Capolino R, Pisaneschi E, Agolini E, Rinelli M, Alesi V, Versacci P, Genovese S, Cesario C, Sinibaldi L, Baban A, Bartuli A, Marino B, Cappa M, Dallapiccola B, Novelli A, Digilio MC. KBG syndrome: Common and uncommon clinical features based on 31 new patients. Am J Med Genet A 2020; 182:1073-1083. [PMID: 32124548 DOI: 10.1002/ajmg.a.61524] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 11/08/2019] [Accepted: 01/17/2020] [Indexed: 12/18/2022]
Abstract
KBG syndrome (MIM #148050) is an autosomal dominant disorder characterized by developmental delay, intellectual disability, distinct craniofacial anomalies, macrodontia of permanent upper central incisors, skeletal abnormalities, and short stature. This study describes clinical features of 28 patients, confirmed by molecular testing of ANKRD11 gene, and three patients with 16q24 deletion encompassing ANKRD11 gene, diagnosed in a single center. Common clinical features are reported, together with uncommon findings, clinical expression in the first years of age, distinctive associations, and familial recurrences. Unusual manifestations emerging from present series include juvenile idiopathic arthritis, dysfunctional dysphonia, multiple dental agenesis, idiopathic precocious telarche, oral frenula, motor tics, and lipoma of corpus callosum, pilomatrixoma, and endothelial corneal polymorphic dystrophy. Facial clinical markers suggesting KBG syndrome before 6 years of age include ocular and mouth conformation, wide eyebrows, synophrys, long black eyelashes, long philtrum, thin upper lip. General clinical symptoms leading to early genetic evaluation include developmental delay, congenital malformations, hearing anomalies, and feeding difficulties. It is likely that atypical clinical presentation and overlapping features in patients with multiple variants are responsible for underdiagnosis in KBG syndrome. Improved knowledge of common and atypical features of this disorder improves clinical management.
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Affiliation(s)
- Maria Gnazzo
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Francesca R Lepri
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Maria Lisa Dentici
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Rossella Capolino
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Elisa Pisaneschi
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Emanuele Agolini
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Martina Rinelli
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Viola Alesi
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Paolo Versacci
- Pediatric Cardiology, Department of Pediatrics, Sapienza University, Rome, Italy
| | - Silvia Genovese
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Claudia Cesario
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Lorenzo Sinibaldi
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Anwar Baban
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Andrea Bartuli
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Bruno Marino
- Pediatric Cardiology, Department of Pediatrics, Sapienza University, Rome, Italy
| | - Marco Cappa
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Bruno Dallapiccola
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Antonio Novelli
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Maria Cristina Digilio
- Laboratory of Medical Genetics, Medical Genetics, Rare Diseases, Pediatric Cardiology, and Endocrinology Units, Scientific Rectorate, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
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11
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Abstract
We report the case of a young woman who presented at age 10 years with height on the tenth centile, brachydactyly type E and mild developmental delay. Biochemistry and hormonal profiles were normal. Differential diagnoses considered included Albright hereditary osteodystrophy without hormone resistance (a.k.a pseudopseudohypoparathyroidism), 2q37 microdeletion syndrome and acrodysostosis. She had a normal karyotype and normal FISH of 2q37. Whole genome sequencing (WGS) identified a mutation in the ANKRD11 gene associated with KBG syndrome. We review the clinical features of the genetic syndromes considered, and suggest KBG syndrome be considered in patients presenting with syndromic brachydactyly type E, especially if short stature and developmental delay are also present.
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Affiliation(s)
- Renata Libianto
- Bone Division, Garvan Institute of Medical Research, Sydney, Australia; Department of Endocrinology, St Vincent's Hospital Sydney, Australia; Department of Medicine, The University of Melbourne, Australia.
| | - Kathy Hc Wu
- Clinical Genomics Unit, St Vincent's Hospital Sydney, Australia; Discipline of Genetic Medicine, University of Sydney, Australia; School of Medicine, UNSW, Sydney, Australia; Genomics and Epigenetics Division, Garvan Institute of Medical Research, Sydney, Australia
| | - Sophie Devery
- Clinical Genomics Unit, St Vincent's Hospital Sydney, Australia
| | - John A Eisman
- Bone Division, Garvan Institute of Medical Research, Sydney, Australia; Department of Endocrinology, St Vincent's Hospital Sydney, Australia; School of Medicine, UNSW, Sydney, Australia; School of Medicine Sydney, University of Notre Dame, Australia
| | - Jackie R Center
- Bone Division, Garvan Institute of Medical Research, Sydney, Australia; Department of Endocrinology, St Vincent's Hospital Sydney, Australia; School of Medicine, UNSW, Sydney, Australia; School of Medicine Sydney, University of Notre Dame, Australia
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12
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Alves RM, Uva P, Veiga MF, Oppo M, Zschaber FCR, Porcu G, Porto HP, Persico I, Onano S, Cuccuru G, Atzeni R, Vieira LCN, Pires MVA, Cucca F, Toralles MBP, Angius A, Crisponi L. Novel ANKRD11 gene mutation in an individual with a mild phenotype of KBG syndrome associated to a GEFS+ phenotypic spectrum: a case report. BMC Med Genet 2019; 20:16. [PMID: 30642272 PMCID: PMC6332862 DOI: 10.1186/s12881-019-0745-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/03/2019] [Indexed: 11/17/2022]
Abstract
Background KBG syndrome is a very rare autosomal dominant disorder, characterized by macrodontia, distinctive craniofacial findings, skeletal findings, post-natal short stature, and developmental delays, sometimes associated with seizures and EEG abnormalities. So far, there have been over 100 cases of KBG syndrome reported. Case presentation Here, we describe two sisters of a non-consanguineous family, both presenting generalized epilepsy with febrile seizures (GEFS+), and one with a more complex phenotype associated with mild intellectual disability, skeletal and dental anomalies. Whole exome sequencing (WES) analysis in all the family members revealed a heterozygous SCN9A mutation, p.(Lys655Arg), shared among the father and the two probands, and a novel de novo loss of function mutation in the ANKRD11 gene, p.(Tyr1715*), in the proband with the more complex phenotype. The reassessment of the phenotypic features confirmed that the patient fulfilled the proposed diagnostic criteria for KBG syndrome, although complicated by early-onset isolated febrile seizures. EEG abnormalities with or without seizures have been reported previously in some KBG cases. The shared variant, occurring in SCN9A, has been previously found in several individuals with GEFS+ and Dravet syndrome. Conclusions This report describe a novel de novo variant in ANKRD11 causing a mild phenotype of KGB syndrome and further supports the association of monogenic pattern of SCN9A mutations with GEFS+. Our data expand the allelic spectrum of ANKRD11 mutations, providing the first Brazilian case of KBG syndrome. Furthermore, this study offers an example of how WES has been instrumental allowing us to better dissect the clinical phenotype under study, which is a multilocus variation aggregating in one proband, rather than a phenotypic expansion associated with a single genomic locus, underscoring the role of multiple rare variants at different loci in the etiology of clinical phenotypes making problematic the diagnostic path. The successful identification of the causal variant in a gene may not be sufficient, making it necessary to identify other variants that fully explain the clinical picture. The prevalence of blended phenotypes from multiple monogenic disorders is currently unknown and will require a systematic re-analysis of large WES datasets for proper diagnosis in daily practice.
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Affiliation(s)
- Rita Maria Alves
- Postgraduate Program in Interactive Processes of Organs and Systems - Federal University of Bahia, Salvador, Brazil.,Research group Epi-Genétic, Salvador, Bahia, Brazil
| | - Paolo Uva
- Centre for Advanced Studies, Research and Development in Sardinia (CRS4), Science and Technology Park Polaris, Pula, Italy
| | - Marielza F Veiga
- Postgraduate Program in Interactive Processes of Organs and Systems - Federal University of Bahia, Salvador, Brazil.,EEG Service and Clinical Outpatient of Epilepsy, University Hospital Complex Professor Edgard Santos (C-HUPES), Federal University of Bahia, Salvador, Bahia, Brazil
| | - Manuela Oppo
- Department of Biomedical Science, University of Sassari, Sassari, Italy
| | | | | | | | - Ivana Persico
- Institute of Genetic and Biomedical Research, National Research Council (CNR), Cittadella Universitaria di Cagliari, 09042, Monserrato, Cagliari, Italy
| | - Stefano Onano
- Department of Biomedical Science, University of Sassari, Sassari, Italy.,Institute of Genetic and Biomedical Research, National Research Council (CNR), Cittadella Universitaria di Cagliari, 09042, Monserrato, Cagliari, Italy
| | - Gianmauro Cuccuru
- Centre for Advanced Studies, Research and Development in Sardinia (CRS4), Science and Technology Park Polaris, Pula, Italy
| | - Rossano Atzeni
- Centre for Advanced Studies, Research and Development in Sardinia (CRS4), Science and Technology Park Polaris, Pula, Italy
| | - Lauro C N Vieira
- Clinic Ponto Alto diagnostic by Image, São Marcos, Salvador, Bahia, Brazil
| | - Marcos V A Pires
- Research group Epi-Genétic, Salvador, Bahia, Brazil.,Faculty of Medicine of the ABC, São Paulo, Brazil
| | - Francesco Cucca
- Department of Biomedical Science, University of Sassari, Sassari, Italy.,Institute of Genetic and Biomedical Research, National Research Council (CNR), Cittadella Universitaria di Cagliari, 09042, Monserrato, Cagliari, Italy
| | - Maria Betânia P Toralles
- Postgraduate Program in Interactive Processes of Organs and Systems - Federal University of Bahia, Salvador, Brazil
| | - Andrea Angius
- Department of Biomedical Science, University of Sassari, Sassari, Italy. .,Institute of Genetic and Biomedical Research, National Research Council (CNR), Cittadella Universitaria di Cagliari, 09042, Monserrato, Cagliari, Italy.
| | - Laura Crisponi
- Department of Biomedical Science, University of Sassari, Sassari, Italy.,Institute of Genetic and Biomedical Research, National Research Council (CNR), Cittadella Universitaria di Cagliari, 09042, Monserrato, Cagliari, Italy
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13
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Spengler S, Oehl-Jaschkowitz B, Begemann M, Hennes P, Zerres K, Eggermann T. Haploinsufficiency of ANKRD11 (16q24.3) Is Not Obligatorily Associated with Cognitive Impairment but Shows a Clinical Overlap with Silver-Russell Syndrome. Mol Syndromol 2013; 4:246-9. [PMID: 23885231 DOI: 10.1159/000351765] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2013] [Indexed: 11/19/2022] Open
Abstract
Microdeletions in 16q24.3 are associated with intellectual disability and a specific phenotype, e.g. short stature and a prominent forehead. The 16q24.3 microdeletion syndrome shows a broad phenotypic overlap with the KBG syndrome, which is caused by mutations within the ANKRD11 gene. Furthermore, both KBG and the 16q24.3 microdeletion syndromes show clinical findings reminiscent of Silver-Russell syndrome (SRS), an imprinting disorder characterized by severe primordial growth retardation. In a cohort of patients referred as SRS, we previously identified a 16q24.3 deletion, but at that time, only patients with larger imbalances in 16q24.3 and intellectual disability had been published. Considering the recent description of the ANKRD11 gene as the causative factor for the 2 16q24.3-associated disorders, we now classified our patient as a 16q24.3 microdeletion syndrome patient exhibiting some characteristic features but normal intelligence. Our case illustrates the broad clinical spectrum associated with microdeletions, and we confirm that the 16q24.3 microdeletion syndrome is a further microdeletion syndrome with very variable expressivity. Indeed, our case is the first 16q24.3 patient of normal intelligence, but we assume that this variant is present in further mentally healthy probands which have not yet been tested. In conclusion, the detection of the 16q24.3 deletion in a proband of unremarkable intellectual capacities once again illustrates the need to perform molecular karyotyping in dysmorphic patients with normal intelligence.
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Affiliation(s)
- S Spengler
- Institut für Humangenetik, RWTH Aachen, Aachen, Germany
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