The molecular basis of alpha thalassemia in India. Its interaction with the sickle cell gene.
The alpha globin genotype of a total of 282 Indians from Orissa state has been analyzed. The overall alpha thalassemia gene frequency is 0.29, most frequently caused by the -alpha 3.7 and -alpha 4.2 deletions. In one family a novel -alpha 3.5 deletion removing the alpha 1 globin gene with some of its flanking sequences has been found, suggesting further sequence homology of the alpha globin gene cluster 3' to the alpha 1 globin gene. Patients with sickle cell disease and alpha thalassemia had higher hemoglobin (Hb) levels, RBC counts, and Hb A2 levels, and lower reticulocyte counts, MCV, MCH, and Hb F levels than those with a normal alpha genotype. The frequency of splenomegaly was not influenced by the alpha globin genotype. A higher prevalence of alpha thalassemia was found in patients greater than or equal to 10 years of age than in the younger group, suggesting a possible advantageous effect of alpha thalassemia on the survival of patients with sickle cell disease.
Kulozik
A E
AE
Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, England.
Kar
B C
BC
Serjeant
G R
GR
Serjeant
B E
BE
Weatherall
D J
DJ
D000367:Age Factors; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D004262:DNA Restriction Enzymes; D005787:Gene Frequency; D005914:Globins / Q000235:genetics*; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007194:India / Q000208:ethnology; D013789:Thalassemia / Q000097:blood / Q000235:genetics*
D005914:Globins; D004262:DNA Restriction Enzymes