Analysis of Fcgamma receptor haplotypes in rheumatoid arthritis: FCGR3A remains a major susceptibility gene at this locus, with an additional contribution from FCGR3B.

The Fcgamma receptors play important roles in the initiation and regulation of many immunological and inflammatory processes, and genetic variants (FCGR) have been associated with numerous autoimmune and infectious diseases. The data in rheumatoid arthritis (RA) are conflicting and we previously demonstrated an association between FCGR3A and RA. In view of the close molecular proximity with FCGR2A, FCGR2B and FCGR3B, additional polymorphisms within these genes and FCGR haplotypes were examined to refine the extent of association with RA.

Malaria is not responsible for the selection of TCR beta-subunit variable gene haplotypes in The Gambia.

Previous work has shown that a single haplotype of the T-cell antigen receptor beta-subunit (TCRB) locus is predominant in African populations. This is likely to be due to selection pressure for gene(s) that protect children against disease. This study has tested the hypothesis that malaria is the responsible selection pressure, due to its impact on child mortality.

Unique TCR beta-subunit variable gene haplotypes in Africans.

This study investigated polymorphisms of genes in two regions of the T-cell antigen receptor beta-subunit (TCRB) locus, including BV9S2P, and BV6S7 in a 5' linkage group, and BV8S3, BV24S1, BV25S1, BV18S1, BV2S1, BV15S1 and BV3S1 in a 3' linkage group. These loci have been genotyped in individuals from five regions in Africa, including The Gambia, Nigeria, Cameroon, Tanzania, and Zambia, and in individuals from northern Britain, northern India, and Papua New Guinea (PNG). In the 3' linkage group, 11 unique haplotypes were identified in the combined African populations; two equally frequent haplotypes represent the majority of African chromosomes.