HLA-A3

A3 is primarily composed of A*03:01 and *03:02 which serotype well with anti-A3 antibodies. There are 26 non-synonymous variants of A*03, 4 nulls, and 22 protein variants. Associated diseases A3 serotype is a secondary risk factor for myasthenia gravis and lower CD8+ levels in hemochromatosis patients. The HFE (Hemochromatosis) locus lies between A3 and B7 within the A3~DQ6 superhaplotype. In HIV HLA-A3 selects HIV evolution for a mutation Gag KK9 epitope and results in a rapid decline in the CD8 T-cell response. CD8 T-cells are responsible for quickly killing HIV infected CD4+ cells. This type of evolved response may not be specific for HLA-A3 and since HIV is capable of adapting quickly in situ to selective factors. ==Alleles==

Associated diseases A*03:01 modulates increased risk for multiple sclerosis ==A3~B haplotypes==

A3-B7 is part of the A3~DQ2 superhaplotype A3-B8 (Romania, svanS) A3~B35 (Bulgaria, Croatia, E. Black Sea) A3~B55 (E. Black Sea) A3~Cw7~B7 A3~B7 is bimodal in frequency in Europe with one node in Ireland and the other in Switzerland, relatively speaking Switzerland appears to be higher. A3~Cw7~B7 is one of the most common multigene haplotypes in the western world, particularly in Central and Eastern Europe. A ~ C ~ B ~ DRB1 ~ DQA1 ~ DQB1 ==References==