Arthritis and HLA-B27 in native North American tribes.

Whereas it is clear that HLA-B27 is increased in many North American natives, the prevalence varies a great deal. There is still a paucity of data on a large number of tribes. There is, however, a suggestion that HLA-B27 positive prevalence follows cultural/linguistic groupings. Reactive arthritis, sacroiliitis, and ankylosing spondylitis also appear to be increased in these people, but their relationship to HLA-B27 and possibly additional genetic predisposing factors is far from clear. Given these data and the known association of infectious agents, more extensive studies are warranted, especially in those tribes with a large enough population to achieve statistical significance.