Intragenic duplication of EHMT1 gene results in Kleefstra syndrome

Mol Cytogenet. 2014 Oct 23;7(1):74. doi: 10.1186/s13039-014-0074-7. eCollection 2014.

Abstract

Background: Kleefstra syndrome is characterized by intellectual disability, muscular hypotonia in childhood and typical facial features. It results from either a microdeletion of or a deleterious sequence variant in the gene euchromatic histone-lysine N-methyltransferase 1 (EHMT1) on chromosome 9q34.

Results: We report on a 3-year-old girl with characteristic symptoms of Kleefstra syndrome. Array comparative genomic hybridization analysis revealed a 145 kilobases duplication spanning exons 2 to 10 of EHMT1. Sequence analysis characterized it as an intragenic tandem duplication leading to a frame shift with a premature stop codon in EHMT1.

Conclusions: This is the first description of an intragenic duplication of EHMT1 resulting in Kleefstra syndrome.

Keywords: Array CGH; EHMT1; Haploinsufficiency; Intragenic duplication; KS; Kleefstra syndrome.

Publication types

  • Case Reports