Correspondence on ‘Factors associated with progression to inflammatory arthritis in first-degree relatives of individuals with RA following autoantibody positive screening in a non-clinical setting’

HLA class I and KIR sequences were determined for Dogon, Fulani, Baka populations of western Africa, Mbuti central Datooga, Iraqw, Hadza eastern Africa. Study 162 individuals identified 134 alleles (41 HLA-A, 60 HLA-B, 33 HLA-C). Common to all are three HLA-C (C1+C*07:01, C1+C*07:02, C2+C*06:02) but no HLA-A or -B. Unexpectedly, novel was in these previously unstudied anthropologically distinctive populations. In contrast, 227 detected, 22 present seven 28 novel. A high diversity A-C-B haplotypes observed. six populations, most represented just once. But the Hadza, a majority occur more than once, with 2 having frequencies 10 intermediate frequencies. The centromeric (cen) part locus exhibits an even balance between cenA cenB telomeric (tel) has telA telB East this changes across continent where is vestigial West All four KIR ligands (A3/11, Bw4, C1, C2) HLA Iraqw encode two ligands, whereas other have encoding one ligands. Individuals African mean 6.8–8.4 different interactions HLA I, compared 2.9–6.5 non-Africans.