Ankylosing spondylitis in West Africans : Evidence for a non-HLA-B27 protective effect.
To determine the prevalence of ankylosing spondylitis in the Fula ethnic group in The Gambia, and relate the disease prevalence to the B27 frequency and subtype distribution of that population.
Methods-215 first degree relatives of 48 B27 positive Fula twin pairs, and 900 adult Fula males were screened for ankylosing spondylitis by clinical and, where appropriate, radiographic means.
The B27 prevalence was determined by PCR/sequence specific oligonucleotides on finger prick samples from 100 unrelated Fula, and B27 subtype distribution by SSCP on unrelated B27 positive individuals.
This data were then compared with the prevalence of ankylosing spondylitis among B27 positive Caucasians.
No case of ankylosing spondylitis was seen.
Six per cent of Fula are B27 positive, of which 32% are B*2703 and 68% B*2705.
Assuming the penetrance of ankylosing spondylitis in B27 positive Fula is the same as in B27 positive Caucasians, the probability of not observing any cases of ankylosing spondylitis among the Fula examined is remote (P=6.7 x 10-6).
Similarly, the chance of not seeing any cases among those expected to be either B*2705 or B*2703 was small (P=3.2 x l0-4 for B*2705, and P=0.02 for B*2703).
Conclusions-The risk of developing ankylosing spondylitis in B27 positive Fula is lower than in B27 positive Caucasians. (...)
Mots-clés Pascal : Spondylarthrite ankylosante, Homme, Ethnie, Epidémiologie, Gambie, Afrique, Prévalence, Système HLA, DNA, Réaction chaîne polymérase, Polymorphisme conformation simple brin, Exploration, Déterminisme génétique, Négroïde, Chronique, Système ostéoarticulaire pathologie, Rhumatisme inflammatoire, Spondylarthropathie, Biologie moléculaire, HLA-B27
Mots-clés Pascal anglais : Ankylosing spondylitis, Human, Ethnic group, Epidemiology, Gambia, Africa, Prevalence, HLA-System, DNA, Polymerase chain reaction, Single strand conformation polymorphism, Exploration, Genetic inheritance, Negroid, Chronic, Diseases of the osteoarticular system, Inflammatory joint disease, Spondylarthropathy, Molecular biology
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0176908
Code Inist : 002B15D. Création : 21/05/1997.