Background: Maple syrup urine disease (MSUD) is a rare autosomal recessive metabolic disorder caused by variants in any of the following genes: BCKDHA, BCKDHB, and DBT gene. Previous reports have highlighted a variety of common causing genes and variants among different ethnic groups affected by MSUD. This study is the first to describe the molecular characteristics, potential common variants, clinical phenotypes, and treatment outcomes of 20 Thai MSUD patients before the implementation of expanded newborn screening in Thailand.
View Article and Find Full Text PDFBackground And Objectives: Exome sequencing (ES) demonstrates a 20-50 percent diagnostic yield for patients with a suspected monogenic neurologic disease. Despite the proven efficacy in achieving a diagnosis for such patients, multiple barriers for obtaining exome sequencing remain. This study set out to assess the efficacy of ES in patients with primary neurologic phenotypes who were appropriate candidates for testing but had been unable to pursue clinical testing.
View Article and Find Full Text PDFHereditary spastic paraplegia (HSP) is a group of neurodegenerative diseases with a high genetic and clinical heterogeneity. Numerous HSP patients remain genetically undiagnosed despite screening for known genetic causes of HSP. Therefore, identification of novel variants and genes is needed.
View Article and Find Full Text PDFThe homologous genes GTPBP1 and GTPBP2 encode GTP-binding proteins 1 and 2, which are involved in ribosomal homeostasis. Pathogenic variants in GTPBP2 were recently shown to be an ultra-rare cause of neurodegenerative or neurodevelopmental disorders (NDDs). Until now, no human phenotype has been linked to GTPBP1.
View Article and Find Full Text PDFThe OTUD6B and ZMIZ1 genes were recently identified as causes of syndromic intellectual disability (ID) with shared phenotypes of facial dysmorphism, distal limb anomalies, and seizure disorders. OTUD6B- and ZMIZ1-related ID are inherited in autosomal recessive and autosomal dominant patterns, respectively. We report a 5-year-old girl with developmental delay, facial phenotypes resembling Williams syndrome, and cardiac defects.
View Article and Find Full Text PDFWe conducted targeted next-generation sequencing (TGS) and/or whole exome sequencing (WES) to assess the genetic profiles of clinically suspected retinitis pigmentosa (RP) in the Korean population. A cohort of 279 unrelated Korean patients with clinically diagnosed RP and available family members underwent molecular analyses using TGS consisting of 88 RP-causing genes and/or WES with clinical variant interpretation. The combined genetic tests (TGS and/or WES) found a mutation in the 44 RP-causing genes and seven inherited retinal disease (IRD)-causing genes, and the total mutation detection rate was 57%.
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