title: Analysis of genetic variants of class II cytokine and their receptor genes in psoriasis patients of two ethnic groups from the Volga-Ural region of Russia.
abstract: BACKGROUND
  The molecular basis of pathogenesis of psoriasis remains unclear, but one unifying hypothesis of disease aetiology is the cytokine network model. The class II cytokines (CF2) and their receptors (CRF2) are all involved in the inflammatory processes and single nucleotide polymorphisms (SNPs) in respective genes have been associated with psoriasis in a previous study of the Estonian population.
  
  
  OBJECTIVE
  We performed a replication study of 47 SNPs in CF2 and CRF2 genes in independent cohorts of psoriasis patients of two ethnic groups (Russians and Bashkirs) from the Volga-Ural region of Russia.
  
  
  METHODS
  DNA was obtained from 395 psoriasis patients of two ethnic groups from the Volga-Ural region of Russia and 476 ethnically matched controls. 47 SNPs in the loci of the genes encoding Class II cytokines and their receptors were selected by SNPbrowser version 3.5. Genotyping was performed using the SNPlex™ (Applied Biosystems) platform.
  
  
  RESULTS
  The genetic variant rs30461 previously associated in original case-control study in Estonians, was also associated in Russians (corrected P-value (Pc=0.008, OR=0.44), but did not reach statistical significance in the Bashkir population. Additionally, the haplotype analysis provided that CC haplotype formed by the SNPs rs30461 and rs955155 had a protective effect in Russians (Pc=0.0024, OR=0.44), supporting the involvement of this locus in the protection against psoriasis. Combined meta-analysis of three populations, including 943 psoriasis patients and 812 healthy controls, showed that the IL29 rs30461 C-allele was not associated with decreased risk of psoriasis (P=0.165, OR=0.68). Moreover, stratification of studies by ethnicity revealed a significant association in the European cohort (P=9.506E-006, OR=0.53).
  
  
  CONCLUSIONS
  Therefore, there is no overall evidence of association between psoriasis and SNP rs30461 of the IL29 gene, but there is some evidence to suggest that an association exists in Europeans. However, this current concept should be considered as preliminary and the results need to be confirmed in future independent studies.
authors: Institute of Biochemistry and Genetics, Ufa Scientific Center of Russian Academy of Sciences, Ufa, Russia. elya-4@yandex.ru
authors: Elvira
authors: E
authors: Galimova
authors: Vita
authors: V
authors: Akhmetova
authors: Boris
authors: B
authors: Latipov
authors: Külli
authors: K
authors: Kingo
authors: Ranno
authors: R
authors: Rätsep
authors: Tanel
authors: T
authors: Traks
authors: Sulev
authors: S
authors: Kõks
authors: Elza
authors: E
authors: Khusnutdinova
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D005260:Female; D056726:Genetic Association Studies; D056426:Genetic Loci; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D007372:Interferons; D007378:Interleukins / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D011565:Psoriasis / Q000208:ethnology / Q000235:genetics* / Q000276:immunology; D018123:Receptors, Interleukin / Q000235:genetics*; D018570:Risk Assessment; D012307:Risk Factors; D012426:Russia / Q000453:epidemiology; D055815:Young Adult; D000095022:Interferon Lambda
chemical_list: D007372:Interferons; D007378:Interleukins; D018123:Receptors, Interleukin; C000624353:interferon-lambda, human; D000095022:Interferon Lambda