HLA-A3

HLA-A3 (A3) is an HLA-A serotype. The serotype identifies the more common HLA-A*03 gene products. A3 is more common in Northwestern and Central Europe, Central Asia, India and Arabia. It is less common on the West Pacific Rim, Africa or indigenous populations of the New World.

Serotype
A3 is primarily composed of A*0301 and *0302 which serotype well with anti-A3 antibodies. There are 26 non-synonymous variants of A*03, 4 nulls, and 22 protein variants.

By serotype
A3 serotype is a secondary risk factor for myasthenia gravis, lower CD8+ levels in hemochromatosis patients

By allele
A*0301 modulates increased risk for Multiple Sclerosis

A3-B Haplotypes
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*0301 : C*0702 : B*0702 : DRB1*1501 : DQA1*0102 : DQB1*0602