α-Thalassemia in the American Negro

Sickle Cell Syndromes. I. Hemoglobin SC-α-Thalassemia

“…This is consistent with each parent being heterozygous for a relative]) mild a-thalassemia gene (32). although it is impossible from the evidence available to exclude a double dose of a still milder cu-thalassemia gene in either or both parents.…”

“…with cu-thalassemia trait and HbH disease apparently being the only clearly discernable forms of a-thalassemia in this population. The findings of a detailed study of black families with HbH disease, as reported by Schwartz and Atwater (32), were consistent with this genetic pattern, but because of the mild degree of abnormality found in the globin synthesis studies of heterozygotes, rigorous proof of this hypothesis was lacking. An attempt has also been made to distinguish between mild and more severe forms of cu-thalassemia trait in blacks (34), but a distinction of this kind remains unconvincing with the limited family studies that are available.…”

“…Hemoglobin H disease in American blacks was only first described in 1972 (32,34). The present case brings the total number of documented cases to nine.…”

Trimodality in the proportion of hemoglobin G Philadelphia in heterozygotes: evidence for heterogeneity in the number of human alpha chain loci.

“…These differences are especially interesting in the context of studies on Black persons with Hb H disease (26,27). While these individuals showed a degree of microcytosis similar to that observed in Orientals and Italians with Hb H disease, the course of the disease was milder.…”

α-Thalassemia in Negro Infants

“…a-Thalassemia is a common genetic disorder of hemoglobin synthesis which occurs in many ethnic groups, including Chinese (18), Thai (23,34), Italians (18), and American Negroes (27). Extensive population studies in Thailand have shown a correlation between the a-thalassemia syndromes and the amount of Hb Barts present in the neonatal period (22,23,33,34).…”