title: Sublocalization of an ataxia-telangiectasia gene distal to D11S384 by ancestral haplotyping in Costa Rican families.
abstract: In an effort to localize a gene for ataxia-telangiectasia (A-T), we have genotyped 27 affected Costa Rican families, with 13 markers, in the chromosome 11q22-23 region. Significant linkage disequilibrium was detected for 9/13 markers between D11S1816 and D11S1391. Recombination events observed in these pedigrees places A-T between D11S1819 and D11S1960. One ancestral haplotype is common to 24/54 affected chromosomes and roughly two-thirds of the families. Inferred (ancestral) recombination events involving this common haplotype in earlier generations suggest that A-T is distal to D11S384 and proximal to D11S1960. Several other common haplotypes were identified, consistent with multiple mutations in a single gene. When considered together with all other evidence, this study further sublocalizes the major A-T locus to approximately 200 kb, between markers S384 and S535.
authors.affiliation: Department of Pathology, UCLA School of Medicine 90095-1732, USA.
authors.forename: N
authors.initials: N
authors.lastname: Uhrhammer
authors.forename: E
authors.initials: E
authors.lastname: Lange
authors.forename: O
authors.initials: O
authors.lastname: Porras
authors.forename: A
authors.initials: A
authors.lastname: Naeim
authors.forename: X
authors.initials: X
authors.lastname: Chen
authors.forename: S
authors.initials: S
authors.lastname: Sheikhavandi
authors.forename: S
authors.initials: S
authors.lastname: Chiplunkar
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.forename: S
authors.initials: S
authors.lastname: Dandekar
authors.forename: T
authors.initials: T
authors.lastname: Liang
mesh_terms: D001260:Ataxia Telangiectasia / Q000235:genetics*; D002648:Child; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D003364:Costa Rica; D005260:Female; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium / Q000235:genetics; D008297:Male
chemical_list: D005819:Genetic Markers