scholarly journals Agenesis of the Corpus Callosum with Facial Dysmorphism and Intellectual Disability in Sibs Associated with Compound Heterozygous KDM5B Variants

Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1397
Author(s):  
Sébastien Lebon ◽  
Mathieu Quinodoz ◽  
Virginie G. Peter ◽  
Carole Gengler ◽  
Gaëlle Blanchard ◽  
...  

We studied a family in which the first-born child, a girl, had developmental delay, facial dysmorphism, and agenesis of the corpus callosum (ACC). The subsequent pregnancy was interrupted as the fetus was found to be also affected by ACC. Both cases were heterozygous for two KDM5B variants predicting p (Ala635Thr) and p (Ser1155AlafsTer4) that were shown to be in trans. KDM5B variants have been previously associated with moderate to severe developmental delay/intellectual disability (DD/ID), autism spectrum disorders (ASD), and dysmorphism in a few individuals, but the pathogenetic mechanisms are not clear yet as patients with both monoallelic and biallelic variants have been observed. Interestingly, one individual has previously been reported with ACC and severe ID in association with biallelic KDM5B variants. Together with the observations in this family, this suggests that agenesis of the corpus callosum may be part of the phenotypic spectrum associated with KDM5B variants and that the KDM5B gene should be included in gene panels to clarify the etiology of ACC both in the prenatal and postnatal setting.

Author(s):  
Evan Jiang ◽  
Mark P. Fitzgerald ◽  
Katherine L. Helbig ◽  
Ethan M. Goldberg

AbstractInterleukin-1 receptor accessory protein-like 1 (IL1RAPL1) encodes a protein that is highly expressed in neurons and has been shown to regulate neurite outgrowth as well as synapse formation and synaptic transmission. Clinically, mutations in or deletions of IL1RAPL1 have been associated with a spectrum of neurological dysfunction including autism spectrum disorder and nonsyndromic X-linked developmental delay/intellectual disability of varying severity. Nearly all reported cases are in males; in the few reported cases involving females, the clinical presentation was mild or the deletion was identified in phenotypically normal carriers in accordance with X-linked inheritance. Using genome-wide microarray analysis, we identified a novel de novo 373 kb interstitial deletion of the X chromosome (Xp21.1-p21.2) that includes exons 4 to 6 of the IL1RAPL1 gene in an 8-year-old girl with severe intellectual disability and behavioral disorder with a history of developmental regression. Overnight continuous video electroencephalography revealed electrical status epilepticus in sleep (ESES). This case expands the clinical genetic spectrum of IL1RAPL1-related neurodevelopmental disorders and highlights a new genetic association of ESES.


2021 ◽  
Vol 8 ◽  
pp. 2329048X2110553
Author(s):  
Rea Mittal ◽  
Ashutosh Kumar ◽  
Roger Ladda ◽  
Gayatra Mainali ◽  
Ermal Aliu

Pitt Hopkins-like syndrome 1 (PTHLS1, OMIM # 610042) is an ultra-rare autosomal recessive condition with a prevalence of <1/1,000,000. Intragenic deletions of CNTNAP2 has been implicated in PTHLS1, however to our knowledge a compound heterozygous deletion of exon 4 and a c.1977_1989del13; p.V660Ffsx9 frameshift variant have not been published previously. In this case report, the proband is a seven year old female with PTHLS1, developmental delay, autism spectrum disorder, focal epilepsy, hypotonia, refractory errors, strabismus, and obstructive sleep apnea. Whole exome sequencing analysis revealed biallelic pathogenic variants of the CNTNAP2 gene. Proband has a three year old sister who has who has a similar phenotype including, developmental delay, epilepsy, gait abnormality, refractory errors, strabismus. Family variants were tested and she shared the same CNTNAP2 variants as her sister. The sisters described highlight two novel variants leading to PTHLS1. Genetic workup is essential in identification and management guidance in these populations.


2019 ◽  
Vol 35 (3) ◽  
Author(s):  
Muhammad Imran Naseer ◽  
Mahmood Rasool ◽  
Angham Abdulrahman Abdulkareem ◽  
Adeel G. Chaudhary ◽  
Syed Kashif Zaidi ◽  
...  

Objective: Primary microcephaly (MCPH) is a rare autosomal recessive disorder characterized by impaired congenital reduction of brain size along with head circumference and intellectual disability. MCPH is a heterogeneous disorder and more than twenty four genes associated with this disease have been identified so far. The objective of this study was to find out the novel genes or mutations leading to the genetic defect in a Saudi family with primary microcephaly. Methods: Whole exome sequencing was carried out to find the novel mutation and the results was further validated using Sanger sequencing analysis. This study was done in the Center of excellence in Genomic Medicine and Research, King Abdulaziz University under KACST project during 2017 and 2018. Results: We report a novel compound heterozygous mutations c.797C>T in exon 7 and c.1102G>A in exon 9 of the WD repeat domain 62 (WDR62) (OMIM 604317) gene in two affected siblings in Saudi family with intellectual disability, speech impediments walking difficulty along with primary microcephaly. Two rare, missense variants were detected in heterozygous state in the WDR62 gene in these two affected individuals from the heterozygous parents. Conclusions: A compound heterozygous mutations c.797C>T in exon 7 and c.1102G> A in exon 9 of the WDR62 gene was identified. WDR62 gene is very important gene and mutation can lead to neuro developmental defects, brain malformations, reduced brain and head size. These results should be taken into consideration during prognostic discussions and mutation spectrum with affected patients and their families in the Saudi population. doi: https://doi.org/10.12669/pjms.35.3.36 How to cite this:Naseer MI, Rasool M, Abdulkareem AA, Chaudhary AG, Zaidi SK, Al-Qahtani MH. Novel compound heterozygous mutations in WDR62 gene leading to developmental delay and Primary Microcephaly in Saudi Family. Pak J Med Sci. 2019;35(3):---------.  doi: https://doi.org/10.12669/pjms.35.3.36 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Omid Alavi ◽  
Hossein Jafari Khamirani ◽  
Sina Zoghi ◽  
Afrooz Feili ◽  
Seyed Alireza Dastgheib ◽  
...  

AbstractIn this study, we detected a novel pathogenic variant and a previously reported variant in RAB3GAP1 by whole-exome sequencing (NM_001172435.2: c.1552C>T, p.Gln518*; c.1471C>T, p.Arg491*). The first patient is a 3-year-old girl who presented with bilateral congenital cataracts, developmental delay, abnormal craniofacial features, drug-resistant constipation, and corpus callosum hypoplasia. The proband of the second family is a 13-year-old boy who suffers from developmental delay, quadriplegia, intellectual disability, abnormal craniofacial features, and corpus callosum hypoplasia.


2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Layal Abi Farraj ◽  
Wassim Daoud Khatoun ◽  
Naji Abou Chebel ◽  
Victor Wakim ◽  
Katia Dawali ◽  
...  

Abstract Background Hyperphosphatasia with mental retardation syndrome (HPMRS) is a recessive disorder characterized by high blood levels of alkaline phosphatase together with typical dysmorphic signs such as cleft palate, intellectual disability, cardiac abnormalities, and developmental delay. Genes involved in the glycosylphosphatidylinositol pathway and known to be mutated in HPMRS have never been characterized in the Lebanese population. Case presentation Herein, we describe a pair of monozygotic twins presenting with severe intellectual disability, distinct facial dysmorphism, developmental delay, and increased alkaline phosphatase level. Two individuals underwent whole exome sequencing followed by Sanger sequencing to confirm the co-segregation of the mutation in the consanguineous family. A biallelic loss of function mutation in PGAP3 was detected. Both patients were homozygous for the c.203delC (p.C68LfsX88) mutation and the parents were carriers confirming the founder effect of the mutation. High ALP serum levels confirmed the molecular diagnosis. Conclusion Our findings have illustrated the genomic profile of PGAP3-related HPMRS which is essential for targeted molecular and genetic testing. Moreover, we found previously unreported clinical findings such as hypodontia and skin hyperpigmentation. These features, together with the novel mutation expand the phenotypic and genotypic spectrum of this rare recessive disorder.


2020 ◽  
Vol 41 (5) ◽  
pp. 921-925 ◽  
Author(s):  
Tiana M. Scott ◽  
Hui Guo ◽  
Evan E. Eichler ◽  
Jill A. Rosenfeld ◽  
Kaifang Pang ◽  
...  

2021 ◽  
pp. 1-5
Author(s):  
Ayberk Turkyilmaz ◽  
Erdal Kurnaz ◽  
Atilla Cayir

Intellectual disability (ID) is characterized by limited or insufficient development of mental abilities, including intellectual functioning impairments, such as learning and understanding cause-effect relationships. Some cases have ID as the only finding and are called isolated cases. Conversely, cases accompanied by facial dysmorphism, microcephaly, autism spectrum disorder, epilepsy, obesity, and congenital anomalies are called syndromic developmental delay (DD)/ID. Isolated and syndromic DD/ID cases show extreme genetic heterogeneity. Genetic etiology can be detected in approximately 40% of the cases, whereas chromosomal abnormalities are observed in 25%. Obesity is a multifactorial disease in which both genetic and environmental factors play important roles. The role of heredity in obesity has been reported to be between 40 and 70%. Array-based comparative genomic hybridization (array-CGH) can detect CNVs in the whole genome at a higher resolution than conventional cytogenetic methods. Array-CGH is currently recommended as the first-tier genetic test for ID cases worldwide. In the present study, we aimed to evaluate clinical, radiological, and genetic analyses of a 12-year and 4-month-old girl with microcephaly, ID, and obesity. In the array-CGH analysis, a 3.1-Mb deletion, arr[GRGh37] 10q23.31g23.33 (92745793_95937944)×1 was detected, and this alteration was evaluated to be pathogenic. We consider that haploinsufficiency of the candidate genes (<i>GPR120</i>, <i>KIF11</i>, <i>EXOC6</i>, <i>CYP26A1</i>, <i>CYP26C1</i>, and <i>LGI1</i>) in the deletion region may explain microcephaly, ID, obesity, seizures, and ophthalmological findings in our patient. The investigation of 10q23.31q23.33 microdeletion in cases with syndromic obesity may contribute to molecular genetic diagnosis.


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