title: A 0.7 Mb de novo duplication at 7q21.3 including the genes DLX5 and DLX6 in a patient with split-hand/split-foot malformation.
abstract: Split-hand/split-foot malformation (SHFM1) has been reported to be caused by deletions, duplications or rearrangements involving the 7q21.3 region harboring DSS1, DLX5, and DLX6. We report on a female patient with unilateral syndactyly of the third and fourth fingers of the right hand and overgrowth and lateral deviation of the right great toe. There was a split foot malformation on the right, with absent fifth toe. The left hand was apparently normal and left foot was intact. The patient has no hearing loss. We performed conventional G-banding karyotype analysis, array comparative genomic hybridization (aCGH) and fluorescence in situ hybridization (FISH). G-banding karyotype result was normal 46,XX. However, a duplication of 719 kb (96,303,736-97,022,335; NCBI build36/hg18, March 2006) was identified at the 7q21.3 region by aCGH. The array result was also confirmed by FISH analysis. The duplicated region harbors only DLX5 and DLX6, which are known for their role in SHFM1. Additionally, FISH analysis of parental samples showed de novo origin of this abnormality in the patient. This is the first report that highlights the duplication of 719 kb at 7q21.3, harboring only DLX5 and DLX6 associated with the SHFM1 phenotype.
authors.affiliation: New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York, USA.
authors.forename: Milen
authors.initials: M
authors.lastname: Velinov
authors.forename: Ausaf
authors.initials: A
authors.lastname: Ahmad
authors.forename: Brigette
authors.initials: B
authors.lastname: Brown-Kipphut
authors.forename: Mustafa
authors.initials: M
authors.lastname: Shafiq
authors.forename: Jonathan
authors.initials: J
authors.lastname: Blau
authors.forename: Ruby
authors.initials: R
authors.lastname: Cooma
authors.forename: Philip
authors.initials: P
authors.lastname: Roth
authors.forename: M Anwar
authors.initials: MA
authors.lastname: Iqbal
mesh_terms: D002897:Chromosomes, Human, Pair 7; D005260:Female; D020131:Genes, Duplicate; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D007223:Infant; D017880:Limb Deformities, Congenital / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
chemical_list: C100596:DLX5 protein, human; C491014:DLX6 protein, human; D018398:Homeodomain Proteins; D014157:Transcription Factors