HLA-B46 - B*4601 Allele Frequencies - A2-Cw11(1)-B46

A2-Cw11(1)-B46

This haplotype is unique in several regards, first and most importantly the B46 serotype is not from Africa, this distinguishes it from every other known B serotype. It is the result of a recombination event between B62(B*1501) and an HLA-C allele within Asia. This event happened recently as there is only one major allele and minor alleles are at trace frequencies. There has been some recombination between this haplotype, A24 and A11 bearing alleles, probably in a local (or tribal population). B46 is found wherever Asian wet-rice farming peoples have traveled and is found at low frequencies in non-farming indigenous groups. The one exception is the Ninhvet of Siberia and the Eastern Tlinglet of Alaska. This B46 contribution appears to have been recent. Because of the numbers of people represented by the sample groups, and its relative high frequency in those group A2-B46 is one of the most frequent, if not the most frequent A-B haplotype in the world, even though it is absent from the indigenous populations of most peoples in the world.

HLA A2-B46 haplotype frequencies
freq Rank in
ref. Population (%) Pop.
Buyi 16.6 1 1
Miao 13.6 1
Singapore
(Chinese)
11.4 2
Chaoshan 10.1 1
Southern Han 7.8 2
VietNam 7.8 1
Thai 7.2 1
Thai Chinese 4.0
Japanese 3.3 4
Li 3.0
Korea 2.8
Uygar 2.7
Manchu 2.6
Inner Mong. 1.9
Northern Han 1.8
1 highest freq. A-B hap in Asia.

This haplotype is unique in several regards, first and most importantly the B46 serotype is not from Africa, this distinguishes it from every other major B serotype except B*48. It is the result of a recombination event between B62(B*1501) and an HLA-C allele within Asia. This event happened recently as there is only one major allele and minor alleles are at trace frequencies. There has been some recombination between this haplotype, A24 and A11 bearing alleles, probably in a local (or tribal population). B46 is found wherever Asian wet-rice farming peoples have traveled and is found at low frequencies in non-farming indigenous groups. The one exception is the Ninhvet of Siberia and the Eastern Tlinglet of Alaska. This B46 contribution appears to have been recent. Because of the numbers of people represented by the sample groups, and its relative high frequency in those group A2-B46 is one of the most frequent, if not the most frequent A-B haplotype in the world, even though it is absent from the indigenous populations of most peoples in the world.

The most common haplotype, and probably the ancestral haplotype given its distribution from the Ninhivet to Indonesia is:

A*0207 : C*0102 : B*4601 : DRB1*0901 : DQA1*0302 : DQB1*0303

A different haplotype that is more common in Korea and Japan is

A*0207 : C*0102 : B*4601 : DRB1*0803 : DQA1*0103 : DQB1*0601

B46, or a closely linked allele may have been under positive selection in rice farmers of Asia.

Read more about this topic:  HLA-B46, B*4601 Allele Frequencies