Localization of PSORS1 to a haplotype block harboring HLA-C and distinct from corneodesmosin and HCR

Hum Genet. 2005 Dec;118(3-4):466-76. doi: 10.1007/s00439-005-0048-2. Epub 2005 Oct 19.

Abstract

Psoriasis is a complex inflammatory disease of the skin affecting 1-2% of the Caucasian population. Associations with alleles from the HLA class I region (now known as PSORS1), particularly HLA-Cw*0602, were described over 20 years ago. However, extensive linkage disequilibrium (LD) within this region has made it difficult to identify the true susceptibility allele from this region. A variety of genes and regions from a 238-kb interval extending from HLA-B to corneodesmosin (CDSN) have been proposed to harbor PSORS1. In order to identify the minimum block of LD in the MHC class I region associated with psoriasis we performed a comprehensive case/control and family-based association study on 242 Northern European psoriasis families and two separate European control populations. High resolution HLA typing of HLA-A, -B and -C alleles was performed, in addition to the genotyping of 18 polymorphic microsatellites and 36 SNPs from a 772-kb segment of the HLA class I region harboring the previously described interval. This corresponded on average to one SNP every 7 kb in the candidate 238 kb region. With all tests, the association was the strongest with single markers and haplotypes from a block of LD harboring HLA-C and SNP n.9. Logistic regression analyses indicated that association seen with candidate genes from the interval such as CDSN and HCR was entirely dependent on association with HLA-Cw*0602 and SNP n.9-G alleles. The previously reported association with CDSN and HCR was observed to be due to the existence of the associated alleles lying on the most commonly over-transmitted haplotype. Rare over-transmitted haplotypes also harbored HLA-Cw*12 alleles. HLA-Cw*12 family members are closely related to HLA Cw*0602, sharing identical sequences in their alpha-2 domains, peptide-binding pockets A, D and E and all 3' introns. The introduction of a potential binding site for the RUNX/AML family of transcription factors in intron 7, is also specific to these HLA-C alleles. These variants need to be investigated further for their role as PSORS1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Case-Control Studies
  • Chromosome Mapping
  • Genetic Predisposition to Disease
  • Glycoproteins / genetics
  • HLA-C Antigens / genetics*
  • Haplotypes
  • Humans
  • Intercellular Signaling Peptides and Proteins
  • Intracellular Signaling Peptides and Proteins
  • Pedigree
  • Polymorphism, Single Nucleotide
  • Proteins / genetics*
  • Psoriasis / genetics*
  • Regression Analysis

Substances

  • CCHCR1 protein, human
  • CDSN protein, human
  • Glycoproteins
  • HLA-C Antigens
  • Intercellular Signaling Peptides and Proteins
  • Intracellular Signaling Peptides and Proteins
  • PSORS1C1 protein, human
  • Proteins