A rare genetic disorder caused by a KAT6B mutation: phenotypic manifestations based on a clinical case
Abstract
Disorders associated with pathogenic variants in the lysine acetyltransferase 6B (KAT6B) gene, located at chromosome 10q22.2, constitute a clinically heterogeneous group, historically divided into two allelic syndromes: Say–Barber–Biesecker–Young–Simpson syndrome (SBBYSS), regarded as a variant of Ohdo syndrome, and genitopatellar syndrome (GPS). Both conditions typically arise from heterozygous pathogenic variants in the terminal exons of KAT6B. As the number of reported cases with overlapping SBBYSS/GPS phenotypes has increased, these entities are now collectively classified as KAT6B-related disorders or the KAT6B spectrum. Individuals with SBBYSS commonly present with characteristic facial dysmorphic features, generalised hypotonia, joint hypermobility, feeding difficulties, and long thumbs and great toes. Skeletal anomalies, particularly patellar hypoplasia, are frequently observed. Genitopatellar syndrome (GPS) is distinguished by severe developmental delay and genital anomalies.
This report describes an 11-month-old male diagnosed with a KAT6B-related disorder following identification of a heterozygous pathogenic missense variant in the KAT6B gene, confirmed by molecular genetic testing. The phenotype included craniofacial dysmorphism, developmental delay and speech impairment, hypotonia, blepharophimosis, long thumbs, skeletal anomalies, a congenital renal anomaly, and seizures. The clinical presentation exhibited a blend of features characteristic of both SBBYSS and…
Read the paper
Related studies
- Diagnosis and management of glutaric aciduria type I – revised recommendations
- EZH2 Codon 641 Mutations are Common in BCL2-Rearranged Germinal Center B Cell Lymphomas
- Consensus guidelines for the diagnosis and management of pyridoxine‐dependent epilepsy due to α‐aminoadipic semialdehyde dehydrogenase deficiency
- Systemic Metabolomic Changes in Blood Samples of Lung Cancer Patients Identified by Gas Chromatography Time-of-Flight Mass Spectrometry
- Human OTULIN haploinsufficiency impairs cell-intrinsic immunity to staphylococcal α-toxin
- Discovery of Novel Recurrent Mutations in Childhood Early T-Cell Precursor Acute Lymphoblastic Leukemia by Whole Genome Sequencing - a Report From the St Jude Children's Research Hospital - Washington University Pediatric Cancer Genome Project
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.