Analysis of the susceptibility regions to psoriasis in Spanish population:evidence of a major gene involved in psoriasis in 6p21

BACKGROUND: Identification of the susceptibility regions to psoriasis in Sp anish population. Analysis of the chromosomal regions 6p, 17q, 4q and 1cen- q21. PATIENTS AND METHOD: Analysis of 27 Spanish families with psoriasis, Parame tric and nonparametric linkage analysis with 22 polymorphic microsatellite markers in the candidate regions. RESULTS: Evidence of linkage (p < 0,05) using non-parametric methods in chr omosome 6p. Absence of linkage in 17q, 4q and 1cen-q21 regions. CONCLUSION: We present the evidence of a major gene in 6p21.3 involved in p soriasis in Spanish population.