alpha-Thalassemia: prevalence and hematologic findings in American Blacks.
alpha-Thalassemia is common in southeast Asia and the Mediterranean, where the predominant lesion seems to be a deletion of one or more of the four gene loci responsible for alpha-globin chain production. In the United States, the prevalence of alpha-thalassemia in blacks was once thought to be low, but more recent studies show that the prevalence of alpha-thalassemia is high. We measured the globin chain synthetic rations in 144 black Americans to determine the prevalence and hematologic manifestations of alpha-thalassemia in this population. There were 120 subjects with a mean synthetic ration of 0.986 +/- 0.04, with a range of 0.90 to 1.06; these were classified as normal. Five subjects were found to have beta-thalassemia; 19 subjects had mild alpha-thalassemia. The overall gene frequency for alpha-thalassemia was estimated to be 0.07 in this population. The hemoglobin values of subjects with mild alpha-thalassemia were not statistically significantly different from normal black or white control subjects of the same sex, but there was a significant decrease in the mean corpuscular volume and in the mean corpuscular hemoglobin value.
D000328:Adult; D001741:Black or African American; D000368:Aged; D044383:Black People; D005260:Female; D005787:Gene Frequency; D005914:Globins / Q000096:biosynthesis / Q000235:genetics*; D006454:Hemoglobins; D006801:Humans; D008297:Male; D008875:Middle Aged; D013789:Thalassemia / Q000097:blood / Q000453:epidemiology / Q000235:genetics*; D014481:United States
D006454:Hemoglobins; D005914:Globins