Screening for the DAU Allele Cluster of the Rhesus D gene in sickle cell disease

Abstract

Sickle cell disease (SCD) is an autosomal recessive disorder caused by the inheritance of a mutated beta hemoglobin gene. Millions of people throughout the world suffer from SCD mainly of African, Mediterranean, Central and South American descent, it is common in regions with endemic malaria. Various therapies have been suggested for the treatment of SCD such as prophylactic antibiotics, bone marrow transplants, and blood transfusion. The capacity of the blood to carry oxygen rises as a result of blood transfusion. This comes with a risk of alloimmunisation as one of the complications of allogeneic blood transfusion. The aim of the study was to screen for the DAU allele cluster in SCD patients and healthy controls after which the frequencies were determined. This study was a case-control study design; it involved comparing the two groups of people: those with the disease and a very similar group of people who do not have the disease. In this case, 25 samples from Mulago sickle cell clinic acted as the cases and 25 samples from Nakasero blood bank as the controls. Screening for DAU was done using polymerase chain reaction- sequence specific priming which detected the 1136C>T substitution of the DAU. The 25(100%) samples from SCD samples were all positive for the DAU allele cluster, 24(96%) samples from Nakasero blood bank were positive for the DAU allele cluster and one (4%) sample from Nakasero blood bank was negative for the DAU allele cluster. Therefore the frequency of DAU in SCD patients was higher than that in normal controls however the difference was insignificant which implied there is no relationship between the DAU allele cluster and sickle cell disease implying the frequency of DAU is the same between donors and SCD patients. This research was however limited by the small sample size that was used which wasn’t representative of the Ugandan population and a larger sample size is recommended for further studies into DAU.