title: A unique phenotype of 2q24.3-2q32.1 duplication: early infantile epileptic encephalopathy without mesomelic dysplasia.
abstract: The voltage-gated sodium channel genes and HOXD genes are clustered on chromosome 2q, and duplication of this region is associated with 2 clinical phenotypes: early-onset epilepsy and mesomelic dysplasia Kantaputra type, respectively. We report a case involving 2q24.3-2q32.1 duplication encompassing both the voltage-gated sodium channel and HOXD gene clusters, which were detected by a comparative genomic hybridization array. The associated clinical features were early-infantile-onset epilepsy, hypoplastic left heart syndrome, and global developmental delay. However, no features of mesomelic dysplasia were found. A fluorescent in situ hybridization study showed that the noncontiguous insertion of the duplicated chromosome 2q segment into chromosome 6q was inherited from the father, who has a balanced insertional translocation. The unique genotype-phenotype correlation in the present case suggests that dosage-sensitive effects might apply only to the voltage-gated sodium channel genes.
authors: 1Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors: Byung Chan
authors: BC
authors: Lim
authors: Byung-Joo
authors: BJ
authors: Min
authors: Woong-Yang
authors: WY
authors: Park
authors: Sun Kyung
authors: SK
authors: Oh
authors: Mi Jung
authors: MJ
authors: Woo
authors: Jin Sun
authors: JS
authors: Choi
authors: Ki Joong
authors: KJ
authors: Kim
authors: Yong Seung
authors: YS
authors: Hwang
authors: Jong Hee
authors: JH
authors: Chae
mesh_terms: D058540:Aicardi Syndrome / Q000235:genetics* / Q000503:physiopathology; D001921:Brain / Q000503:physiopathology; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D055028:Comparative Genomic Hybridization; D002658:Developmental Disabilities / Q000235:genetics / Q000503:physiopathology; D004569:Electroencephalography; D005220:Fathers; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000235:genetics / Q000503:physiopathology; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008297:Male; D010641:Phenotype; D013036:Spasms, Infantile / Q000235:genetics* / Q000503:physiopathology; D014178:Translocation, Genetic; D014314:Trisomy / Q000235:genetics* / Q000503:physiopathology
keywords: 2q duplication; HOXD; comparative genomic hybridization array; epilepsy; hypoplastic left heart syndrome; mesomelic dysplasia; sodium channel