title: Confirmation of psoriasis susceptibility loci on chromosome 6p21 and 20p13 in French families.
abstract: Plaque psoriasis is a chronic inflammatory disorder of the skin. It is inherited as a multifactorial trait, with a strong genetic component. Linkage studies have identified a large number of disease loci, but very few could be replicated in independent family sets. In this study, we present the results of a genome-wide scan carried out in 14 French extended families. Candidate regions were then tested in a second set of 32 families. Analysis of the pooled samples confirmed linkage to chromosomes 6p21 (Z(MLB) score=3.5, P=0.0002) and 20p13 (Z(MLB) score=2.9, P=0.002), although there was little contribution of the second family set to the 20p13 linkage signal. Moreover, we identified four additional loci potentially linked to psoriasis. The major histocompatibility complex region on 6p21 is a major susceptibility locus, referred to as PSORS1, which has been found in most of the studies published to date. The 20p13 locus segregates independently of PSORS1 in psoriasis families. It has previously been thought to be involved in the predisposition to psoriasis and other inflammatory disorders such as atopic dermatitis (AD) and asthma. Although psoriasis and AD rarely occur together, this reinforces the hypothesis that psoriasis is influenced by genes with general effects on inflammation and immunity.
authors.affiliation: Centre National de Génotypage, Evry, France. flesueur@igr.fr
authors.forename: Fabienne
authors.initials: F
authors.lastname: Lesueur
authors.forename: Caroline
authors.initials: C
authors.lastname: Lefèvre
authors.forename: Cristina
authors.initials: C
authors.lastname: Has
authors.forename: Michel
authors.initials: M
authors.lastname: Guilloud-Bataille
authors.forename: Tiphaine
authors.initials: T
authors.lastname: Oudot
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Mahé
authors.forename: Morad
authors.initials: M
authors.lastname: Lahfa
authors.forename: Samira
authors.initials: S
authors.lastname: Mansouri
authors.forename: Haydeh
authors.initials: H
authors.lastname: Mosharraf-Olmolk
authors.forename: Eric
authors.initials: E
authors.lastname: Sobel
authors.forename: Simon
authors.initials: S
authors.lastname: Heath
authors.forename: Mark
authors.initials: M
authors.lastname: Lathrop
authors.forename: Marie-Hélène
authors.initials: MH
authors.lastname: Dizier
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Prud'Homme
authors.forename: Judith
authors.initials: J
authors.lastname: Fischer
mesh_terms: D000328:Adult; D002890:Chromosomes, Human, Pair 20; D002896:Chromosomes, Human, Pair 6; D005192:Family Health; D005260:Female; D005602:France; D008040:Genetic Linkage; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000235:genetics*