Wiedemann-Steiner syndrome due to novel nonsense variant of KMT2A gene in a case / 中华医学遗传学杂志

ABSTRACT

OBJECTIVE@#To explore the genetic basis for a child with unexplained global developmental delay (GDD), seizure, and facial deformity.@*METHODS@#Whole exome sequencing (WES) was carried out for the patient. Candidate variants were verified by Sanger sequencing of the patient and his parents.@*RESULTS@#WES revealed that the patient has carried a previously unreported de novo heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene, Based on the American College of Medical Genetics and Genomics standards and guidelines, the c.4906C>T variant of KMT2A gene was predicted to be pathogenic (PVS1+ PS2+ PM2+PP3).@*CONCLUSION@#The heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene probably underlay the disease in the child. Above finding has enriched the spectrum of pathogenic variants of the KMT2A gene.