The prevalence of alpha-thalassaemia and various globin gene rearrangements was determined in 1992 individuals living on 11 islands in French Polynesia.
The gene frequencies for alpha+-thalassaemia (almost exclusively the - alpha3.7III deletion form) range from 5.3% to 19.2%. Haematological indices on 177 heterozygotes and 27 homozygotes for the - alpha3.7III variant showed considerable overlap with indices of normal individuals ; although there was a broad correlation of average indices with alpha-globin genotype, individual values were a poor indication of genotype.
A non-deletion form of alpha+-thalassaemia (alphaalphaTh), triplicated alpha genes (alphaalphaalpha) and single zeta gene (-zêta) chromosomes were present at low frequencies (<1%), whereas triplicated gamma gene (gammagammagamma) and triplicated zêta (zêtazêtazêta) arrangements were more common (1.1-16.3%). alpha0-thalassaemia, probably introduced from Southeast Asia in the early part of this century, was observed in a number of individuals of Chinese and Chinese/Polynesian ancestry.
Because of the high frequency of alpha+-Thalassaemia on some islands, it therefore seems likely that haemoglobin H disease (resulting from the interaction between alpha0 and alpha+-thalassaemia) must occur in parts of French Polynesia.
Mots-clés Pascal : Thalassémie alpha, Globine, Réarrangement génique, Gène, Prévalence, Hémoglobine H, Epidémiologie, Polynésie française, Polynésie, Océanie, Homme, Hémopathie, Anémie hémolytique, Hémoglobinopathie, Maladie héréditaire, Hémoglobine instable
Mots-clés Pascal anglais : alpha-Thalassemia, Globin, Gene rearrangement, Gene, Prevalence, Hemoglobin H, Epidemiology, French Polynesia, Polynesia, Oceania, Human, Hemopathy, Hemolytic anemia, Hemoglobinopathy, Genetic disease, Unstable hemoglobin
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 95-0504276
Code Inist : 002B19A01. Création : 01/03/1996.