An increasing number of individuals with intellectual developmental disorder (IDD) and heterozygous variants in BCL11A are identified, yet our knowledge of manifestations and mutational spectrum is lacking. To address this, we performed detailed analysis of 42 individuals with BCL11A-related IDD (BCL11A-IDD, a.k.
View Article and Find Full Text PDFInterstitial deletions involving 6q25 are rare chromosomal abnormalities associated with distinctive phenotypic features. We describe a 9-year-old boy who was followed from his infancy due to his multiple congenital anomalies and complex medical history. Over the years, a number of diagnoses were considered including Cornelia de Lange syndrome, Rubinstein-Taybi syndrome, as well as "a novel genetic disorder.
View Article and Find Full Text PDFConnexin 26 (Cx26), encoded by the GJB2 gene, is a key protein involved in the formation of gap junctions in epithelial organs including the inner ear and palmoplantar epidermis. Pathogenic variants in GJB2 are responsible for approximately 50% of inherited sensorineural deafness. The majority of these variants are associated with autosomal recessive inheritance; however, rare reports of dominantly co-segregating variants have been published.
View Article and Find Full Text PDFDiamond-Blackfan anemia (DBA) is a group of clinically and genetically heterogeneous bone marrow failure disorders with or without congenital anomalies. Variable expressivity and incomplete penetrance have been observed within affected families. Diamond-Blackfan anemia-7 (DBA7), caused by heterozygous mutations in ribosomal protein L11 (RPL11), accounts for approximately 5% of DBA.
View Article and Find Full Text PDFHearing loss represents the most common sensory disability of children. Remarkable advances in the identification of genes underlying nonsyndromic and syndromic hearing loss in just the last 2 decades have led to the ability to determine the specific genetic cause of hearing loss in many children. Surprisingly one gene, GJB2, encoding the protein connexin-26, accounts for about 20 % of sensorineural hearing loss (including in India) and is considered the first tier test in evaluating an infant with unexplained congenital hearing loss.
View Article and Find Full Text PDFAm J Med Genet C Semin Med Genet
February 2004
A multistate Centers for Disease Control and Prevention (CDC) study was designed to investigate the etiology of congenital hearing loss in infants ascertained through state-mandated hearing screening or early hearing loss detection and intervention (EHDI) programs. At least 50% of permanent childhood-onset hearing loss is due to genetic causes, and approximately 20% of all infants with congenital hearing loss have mutations in the GJB2 gene. Another 1% of childhood hearing loss is due to mitochondrial DNA (mtDNA) mutations.
View Article and Find Full Text PDFWe report on a 12-year-old boy who presented with delayed development and CNS dysmyelination. Genetic studies showed a normal 46,XY karyotype by routine cytogenetic analysis, and 46,XY.ish del(18)(q23)(D18Z1+, MBP-) by FISH using a locus-specific probe for the MBP gene (18q23).
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