title: Linkage disequilibrium and CF allele segregation analysis in cystic fibrosis families in Northern Ireland.
abstract: Linkage disequilibrium and cystic fibrosis (CF) allele segregation were analysed in 46 CF families in Northern Ireland. The smaller (+) allele of the KM19/PstI polymorphism and the larger (-) allele of the XV-2c/TaqI polymorphism showed marked linkage disequilibrium with CF. This information can be used to alter the risk of an individual being a carrier of CF away from the expected population risk of 1 in 20. The high-risk genotypes K+K+ or X-X- have a risk of 1 in 10 and the low-risk genotypes K-K- or X+X+ have a risk of 1 in 50. A study of the segregation of CF alleles in the 46 families, using KM19 and Xv-2c, showed preferential inheritance of the paternal (79%), as opposed to the maternal (21%), CF allele by the heterozygous carriers. A mechanism that might explain this observation is discussed.
authors.affiliation: Department of Medical Genetics, Queen's University of Belfast, Belfast City Hospital, Northern Ireland.
authors.forename: A J
authors.initials: AJ
authors.lastname: Hill
authors.forename: C A
authors.initials: CA
authors.lastname: Graham
authors.forename: E D
authors.initials: ED
authors.lastname: Kelly
authors.forename: P J
authors.initials: PJ
authors.lastname: Morrison
authors.forename: N C
authors.initials: NC
authors.lastname: Nevin
mesh_terms: D000483:Alleles; D003550:Cystic Fibrosis / Q000175:diagnosis / Q000235:genetics*; D004247:DNA / Q000235:genetics; D005260:Female; D006580:Genetic Carrier Screening; D005819:Genetic Markers; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D009660:Northern Ireland; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D011296:Prenatal Diagnosis; D012307:Risk Factors
chemical_list: D005819:Genetic Markers; D004247:DNA