title: Mapping one form of autosomal dominant postaxial polydactyly type A to chromosome 7p15-q11.23 by linkage analysis.
abstract: Postaxial polydactyly type-A (PAP-A) in humans is an autosomal dominant trait characterized by an extra digit in the ulnar and/or fibular side of the upper and/or lower extremities. The extra digit is well formed and articulates with the fifth, or extra, metacarpal/metatarsal, and thus it is usually functional. In order to map the gene responsible for PAP-A, we studied a five-generation Indian family of 37 individuals (15 of whom were affected). A genomewide search with highly informative polymorphic markers on part of the pedigree showed linkage between the PAP-A phenotype and markers on chromosome 7p15-q11.23 (no crossovers were found with D7S526, D7S795, D7S528, D7S521, D7S691, D7S667, D7S478, D7S1830, D7S803, D7S801, or ELN). The highest LOD score was obtained with marker D7S801 (zeta max = 4.21; theta = 0). Haplotype analysis enabled the mapping of the PAP-A phenotype in this family between markers D7S2848 and D7S669. Analysis of additional families with PAP-A will narrow down the critical genomic region, facilitate positional cloning of the PAP-A gene, and/or uncover potential genetic heterogeneity.
authors.affiliation: Department of Genetics and Microbiology, Geneva Medical School, Switzerland.
authors.forename: U
authors.initials: U
authors.lastname: Radhakrishna
authors.forename: J L
authors.initials: JL
authors.lastname: Blouin
authors.forename: H
authors.initials: H
authors.lastname: Mehenni
authors.forename: U C
authors.initials: UC
authors.lastname: Patel
authors.forename: M N
authors.initials: MN
authors.lastname: Patel
authors.forename: J V
authors.initials: JV
authors.lastname: Solanki
authors.forename: S E
authors.initials: SE
authors.lastname: Antonarakis
mesh_terms: D002874:Chromosome Mapping; D002897:Chromosomes, Human, Pair 7; D004247:DNA; D005260:Female; D005799:Genes, Dominant; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D010375:Pedigree; D017689:Polydactyly / Q000000981:diagnostic imaging / Q000235:genetics*; D011110:Polymorphism, Genetic; D011859:Radiography
chemical_list: D004247:DNA