This gene rich region includes HLA family genes, particularly HLA-B and HLA-C that are candidates within the lymphocyte associated locus, and actually overlap with the psoriasis candidate locus identified previously via linkage mapping studies and includes PSORS1C1 and PSORS1C2, showing the relatedness of these two loci on chromosome 6p21 [69], although conditional analyses adjusting for total white blood cell count validate these as primarily independent effects. This evidence concerns the gene HLA-B and psoriasis.