Haptoglobin gene polymorphisms in sickle cell disease patients with different beta s-globin gene haplotypes

ABSTRACT

To investigate the prevalence of haptoglobin [Hp] gene alleles in Kuwaiti sickle cell disease [SCD] patients, who generally have a mild phenotype, and compare the pattern to Nigerian SCD patients whose SCD phenotype is more severe. Hp genotyping was carried out in a group of 82 and 54 SCD patients from Kuwait and Nigeria, respectively, and appropriate Hb AA controls. The Hp genotyping was done using a PCR technique followed by agarose gel electrophoresis. The frequency of the Hp-2 allele was 73.8% among Kuwaiti SCD patients, while the Hp-1 allele predominated among Nigerian patients [60.7%]. However, the differences were not significant [p > 0.05] when the allele distributions were compared between Kuwaiti SCD and their AA counterparts or between Nigerian SCD and their AA controls. There was no association of Hp-2 allele with frequent vaso-occlusive crisis among the Kuwaiti SCD patients. The distribution of Hp alleles appears to follow ethnic and geographical trends. Their role in the pathophysiology of pain crisis is not clear