title: Novel homozygous mutations in the WNT10B gene underlying autosomal recessive split hand/foot malformation in three consanguineous families.
abstract: Split-hand/split-foot malformation (SHFM), representing variable degree of median clefts of hands and feet, is a genetically heterogeneous group of limb malformations with seven loci mapped on different human chromosomes. However, only 3 genes (TP63, WNT10B, DLX5) for the seven loci have been identified. The study, presented here, described three consanguineous Pakistani families segregating SHFM in autosomal recessive manner. Linkage in the families was searched by genotyping microsatellite markers and mutation screening of candidate gene was performed by Sanger DNA sequencing. Clinical features of affected members of these families exhibited SHFM phenotype with involvement of hands and feet. Genotyping using microsatellite markers mapped the families to WNT10B gene at SHFM6 on chromosome 12q13.11-q13. Subsequently, sequence analysis of WNT10B gene revealed a novel 4-bp deletion mutation (c.1165_1168delAAGT) in one family and 7-bp duplication (c.300_306dupAGGGCGG) in two other families. Structure-based analysis showed a significant conformational shift in the active binding site of mutated WNT10B (p.Lys388Glufs*36), influencing binding with Fzd8. The mutations identified in the WNT10B gene extend the body of evidence implicating it in the pathogenesis of SHFM.
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Pakistan.
authors.forename: Abdul
authors.initials: A
authors.lastname: Aziz
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Pakistan.
authors.lastname: Irfanullah
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Pakistan.
authors.forename: Saadullah
authors.initials: S
authors.lastname: Khan
authors.affiliation: National Institute of Rehabilitation Medicine (NIRM), Islamabad, Pakistan.
authors.forename: Faridullah Khan
authors.initials: FK
authors.lastname: Zimri
authors.affiliation: Department of Biotechnology & Genetic Engineering, Kohat University of Science & Technology (KUST), Kohat, KPK, Pakistan.
authors.forename: Noor
authors.initials: N
authors.lastname: Muhammad
authors.affiliation: National Center for Bioinformatics, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Pakistan.
authors.forename: Sajid
authors.initials: S
authors.lastname: Rashid
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University Islamabad, Pakistan. Electronic address: wahmad@qau.edu.pk.
authors.forename: Wasim
authors.initials: W
authors.lastname: Ahmad
mesh_terms: D001665:Binding Sites; D003241:Consanguinity; D005260:Female; D005808:Genes, Recessive; D008040:Genetic Linkage; D005838:Genotype; D006228:Hand Deformities, Congenital / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D017880:Limb Deformities, Congenital / Q000235:genetics*; D008297:Male; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D017422:Sequence Analysis, DNA / Q000379:methods; D017384:Sequence Deletion; D051153:Wnt Proteins / Q000235:genetics*
chemical_list: D011518:Proto-Oncogene Proteins; C491119:WNT10B protein, human; D051153:Wnt Proteins
keywords: AER; BLAST; Basic Local Alignment Search Tool; DLX5; Deletion and duplication mutations; EDTA; Ethylene diamine tetra acetic acid; FZD; LGA; Lamarckian genetic algorithm; PCR; PDB; PMDB; Polymerase Chain Reaction; Protein Data Bank; Protein Model Database; RMSD; RT-PCR; Reverse transcription polymerase chain reaction; Root-mean-square deviation; SHFM; SHFM6; Split hand foot malformation; TP63; WNT10B; WNT10B gene; apical ectodermal ridge; base pair; bp; cDNA; complementary DNA; del; deletion; distal-less homeobox 5; dup; duplication; frameshift; frizzled; fs; tumor protein p63; wingless-type MMTV integration site family, member 10B