Molecular studies on Yemeni sickle-cell-disease patients: Xmn I polymorphism

Abstract

Our studies of the Saudi population have shown that in patients with mild presentation of sickle-cell disease (SCD) from Saudi Arabia's eastern region, the prevalence of polymorphic sites is high. However, the prevalence is very low in patients with severe SCD from the south-west of the country. We expanded these studies to a group of Yemeni patients with severe SCD, resident in Riyadh. We investigated a total of 60 chromosomes carrying the sickle-cell (Hb S) gene and 14 chromosomes carrying the Hb A gene. Amongst the Hb AA group, the prevalence was 42.9% and 57.1% for the presence (+) and absence (-) of Xmn I polymorphic sites. In the Hb SS individuals, the prevalence of Xmn I polymorphic sites was similar to the prevalence reported in the south-western region of Saudi Arabia.