Phenotypic and Cytogenetic Delineation of Six Korean Children with Kabuki Syndrome

Abstract

Purpose : Kabuki syndrome is a multiple congenital malformation syndrome with mental retardation. It was named after its characteristic appearance, a face resembling that of an actor in a Kabuki play. To date, six Korean cases of Kabuki syndrome have ever been reported. Here, we present the phenoty- pic and genetic characteristics of six patients with Kabuki syndrome. Materials and Methods:Between 2003 and 2009, six Korean girls have been diagnosed and followed up as Kabuki syndrome at Center for Genetic Diseases of Ajou University Hospital. Their clinical and laboratory data were collected and analyzed by the retrospective review of medical records. Results : All six patients showed the characteristic facial dysmorphism and developmental delay. Per- sistent fingertip pads were also found in all patients. Most patients showed postnatal growth retarda- tion (83.3%) and hypotonia (83.3%). Opthalmologic problems were common, particularly for strabismus (83.3%). Congenital heart defects were present in three patients (50%). Skeletal abnormalities including 5th finger shortening (83.3%), clinodactyly (50%), joint hypermobility (50%) and hip dislocation (16.7 %) were also observed. There was no patient who had positive family history for Kabuki syndrome. Cytogenetic and molecular cytogenetic analyses including karyotyping and array CGH could not reveal any underlying genetic cause of Kabuki syndrome. Conclusion : Korean patients with Kabuki syndrome showed a broad spectrum of clinical features af- fecting multiple organ systems. Although clinical manifestations of Kabuki syndrome have been well established, our results failed to detect recurrent chromosome aberrations which could cause Kabuki syndrome. Its natural history and genetic background remains to be further studied for providing appro- priate management and genetic counseling.