title: Possible relations between the polymorphisms of the cytokines IL-19, IL-20 and IL-24 and plaque-type psoriasis.
abstract: The aim of present study was to elucidate the role of the interleukin (IL)-24 gene in predicting risk for plaque-type psoriasis and to describe the linkage disequilibrium (LD) pattern emerging from the genes of IL-19, IL-20 and IL-24. Genes encoding IL-19, IL-20 and IL-24 locate in the region q32 of chromosome 1. The association between the single-nucleotide polymorphisms (SNPs) or haplotypes of the IL-24 gene and the susceptibility of psoriasis was not found. However, a significant protective effect of the combined haplotype CAAAC of IL-20 and IL-24 genes against plaque-type psoriasis was established (OR 0.154). Protective effect against psoriasis was also observed with haplotype TGGGT (OR 0.591) and haplotype CGAGT (OR 0.457). Performing a comprehensive analysis using the data regarding SNPs of IL-24 gene together with the previously published data regarding IL-19 and IL-20 SNPs, we identified two haplotype blocks within the region q32 of chromosome 1. The main result of the present study is that while the IL-19/IL-20 extended haplotype CACCGGAA is a significant susceptibility factor for psoriasis (previous study), IL-20/IL-24 haplotypes CAAAC, TGGGT and CGAGT have a significant protective effect. Nevertheless, family-based studies are required to confirm the impact of IL-19, IL-20 and IL-24 genes in the genetic predisposition for psoriasis.
authors.affiliation: Department of Physiology, University of Tartu, Estonia. Sulev.Koks@ut.ee
authors.forename: S
authors.initials: S
authors.lastname: Kõks
authors.forename: K
authors.initials: K
authors.lastname: Kingo
authors.forename: K
authors.initials: K
authors.lastname: Vabrit
authors.forename: R
authors.initials: R
authors.lastname: Rätsep
authors.forename: M
authors.initials: M
authors.lastname: Karelson
authors.forename: H
authors.initials: H
authors.lastname: Silm
authors.forename: E
authors.initials: E
authors.lastname: Vasar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D005260:Female; D016147:Genes, Tumor Suppressor; D020022:Genetic Predisposition to Disease; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics; D007378:Interleukins / Q000235:genetics*; D015810:Linkage Disequilibrium / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011565:Psoriasis / Q000235:genetics*; D000099180:Interleukin-24
chemical_list: D016753:Interleukin-10; D007378:Interleukins; D000099180:Interleukin-24; C421250:IL19 protein, human; C422042:interleukin 20