Non-MHC Sample Clauses

Non-MHC disease susceptibility loci Linkage studies repeatedly failed to detect psoriasis susceptibility loci outside of the MHC, reflecting their lack of power in the identification of genetic determinants of small effect. Conversely, genome-wide association scans have led to the identification of > 20 disease associated regions, the majority of which include at least one immune related gene (Capon, Burden et al. 2012). The function of these positional candidates appears to indicate the pathogenic involvement of a limited number of signalling pathways, mostly related to Th17 cell activation, NF-κB and IFN signalling (Table 1.1.3.2.1). Interestingly, disease associated alleles have also been identified within the ERAP1 gene, which encodes an amino-peptidase involved in the processing of small polypeptides recognised by class I MHC molecules. In keeping with the function of ERAP1 in antigen presentation, an interaction between HLA-C and ERAP1 has been identified, whereby ERAP1 variants confer psoriasis susceptibility only in those individuals carrying HLA-C risk alleles (Strange, Xxxxx et al. 2010).