# Genetic and Phenotypic Spectrum of KMT2D Variants in Taiwanese Case Series of Kabuki Syndrome

## TL;DR

This study explores the genetic and physical traits of Kabuki syndrome in 23 Taiwanese patients, identifying KMT2D gene variants and common symptoms.

## Contribution

The study expands the known genetic and phenotypic spectrum of Kabuki syndrome in the Taiwanese population.

## Key findings

- KMT2D variants were found in 22 out of 23 patients, with missense, nonsense, and frameshift mutations being most common.
- Common clinical features included facial features, intellectual disability, developmental delay, and heart abnormalities in over 60% of patients.

## Abstract

Kabuki syndrome (KS) is a rare genetic disorder characterized by distinct facial features, intellectual disability, and multiple congenital anomalies. We conducted a comprehensive analysis of the genetic and phenotypic spectrum of KS in a Taiwanese patient group of 23 patients. KMT2D variants were found in 22 individuals, with missense (26.1%), nonsense (21.7%), and frameshift (17.4%) variants being the most prevalent. One patient had a KMT2D variant of uncertain significance. The most common clinical characteristics included distinct facial features (100%), intellectual disability (100%), developmental delay (95.7%), speech delay (78.3%), hypotonia (69.6%), congenital heart abnormalities (69.6%), and recurrent infections (65.2%). Other abnormalities included hearing loss (39.1%), seizures (26.1%), cleft palate (26.1%), and renal anomalies (21.7%). This study broadens the mutational and phenotypic spectrum of KS in the Taiwanese population, highlighting the importance of comprehensive genetic testing and multidisciplinary clinical evaluations for diagnosis and treatment.