학술논문

Novel variants in KAT6B spectrum of disorders expand our knowledge of clinical manifestations and molecular mechanisms
Document Type
article
Source
Molecular Genetics & Genomic Medicine. 9(10)
Subject
Biological Sciences
Genetics
Brain Disorders
Congenital Structural Anomalies
Clinical Research
Pediatric
Intellectual and Developmental Disabilities (IDD)
Rare Diseases
Genetic Testing
Aetiology
2.1 Biological and endogenous factors
Congenital
Abnormalities
Multiple
Alleles
Blepharophimosis
Cohort Studies
Congenital Hypothyroidism
Craniofacial Abnormalities
Facies
Genetic Association Studies
Genetic Counseling
Genetic Loci
Genetic Predisposition to Disease
Genotype
Heart Defects
Congenital
Histone Acetyltransferases
Humans
Intellectual Disability
Joint Instability
Kidney
Male
Mutation
Patella
Phenotype
Psychomotor Disorders
Scrotum
Urogenital Abnormalities
CRISPR
Genitopatellar syndrome
KAT6B-related disorders
phenotypic spectrum
Say-Barber-Biesecker-Young-Simpson syndrome
variable expressivity
rare genetic diagnosis
variable expressivity
rare genetic diagnosis
Medicinal and Biomolecular Chemistry
Clinical Sciences
Medicinal and biomolecular chemistry
Language
Abstract
The phenotypic variability associated with pathogenic variants in Lysine Acetyltransferase 6B (KAT6B, a.k.a. MORF, MYST4) results in several interrelated syndromes including Say-Barber-Biesecker-Young-Simpson Syndrome and Genitopatellar Syndrome. Here we present 20 new cases representing 10 novel KAT6B variants. These patients exhibit a range of clinical phenotypes including intellectual disability, mobility and language difficulties, craniofacial dysmorphology, and skeletal anomalies. Given the range of features previously described for KAT6B-related syndromes, we have identified additional phenotypes including concern for keratoconus, sensitivity to light or noise, recurring infections, and fractures in greater numbers than previously reported. We surveyed clinicians to qualitatively assess the ways families engage with genetic counselors upon diagnosis. We found that 56% (10/18) of individuals receive diagnoses before the age of 2 years (median age = 1.96 years), making it challenging to address future complications with limited accessible information and vast phenotypic severity. We used CRISPR to introduce truncating variants into the KAT6B gene in model cell lines and performed chromatin accessibility and transcriptome sequencing to identify key dysregulated pathways. This study expands the clinical spectrum and addresses the challenges to management and genetic counseling for patients with KAT6B-related disorders.