Beta globin gene haplotypes in Bahraini patients with sickle cell anemia

ABSTRACT

Molecular genetic studies were undertaken to determine the haplotype of chromosomes carrying the sickle cell allele in Bahraini patients, and hence allow consideration of the possible source of these alleles. A total of 59 individuals form 19 families were studied. Of these, 35 were affected with sickle cell anaemia, and 24 were carriers. Haplotypes were investigated by PCR amplification of globin target sequences followed by restriction digestion using HindIII, AvaII, HindII, and HinfI polymorphism. In the 19 families the Bs gene was found to be linked to the haplotypes +++++- [also known as the Asian haplotype] in 33 chromosomes [90%], to the haplotype +-+-++ known as the S2 haplotype in 2 chromosome [5%], the haplotype S1 [-++++] in one chromosome [2.5%], and to the haplotype --+--+ found in association with beta thalassaemia in one family [2.5%]. Our study shows that the Asian haplotype is predominant in Bahrain [90%]. This haplotype has previously been found to be linked to a benign sickle cell anaemia. The African haplotype S1 was found in one family only