Hb H disease caused by a homozygosity for the AATAAA-->AATAAG mutation in the polyadenylation site of the alpha 2-globin gene: hematological observations.
We have identified 7 patients with Hb H disease as homozygotes for a mutation in the polyadenylation site (AATAAA-->AATAAG) and have compared their hematological data with those of Hb H patients having other types of alpha-thalassemia determinants. All 7 patients exhibited moderate anemia with microcytosis and hypochromia being similar to that observed in the other patients. Relatives with a heterozygosity for this mutation are borderline microcytic and hypochromic without a significant anemia but with a low in vitro alpha/beta chain synthesis ratio. Analyses of the hemoglobin components identified low levels of Hb A2 and Hb H that were comparable to those found in other patients with Hb H disease; the level of the zeta-chain was low (average 0.14%).
D000293:Adolescent; D000328:Adult; D001483:Base Sequence; D002648:Child; D003241:Consanguinity; D004909:Erythrocyte Indices; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis; D005914:Globins / Q000235:genetics*; D006443:Hemoglobin A2 / Q000032:analysis; D006447:Hemoglobin H / Q000032:analysis; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D011061:Poly A / Q000378:metabolism*; D017085:alpha-Thalassemia / Q000097:blood / Q000235:genetics*
D011061:Poly A; D005914:Globins; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin; D006447:Hemoglobin H