ALLELIC AND GENOTYPIC FREQUENCIES OF ABO AND Rh BLOOD GROUPS AMONG TIGREAN, SAHO AND EROB ETHNIC PEOPLE IN MEKELLE CITY PATIENTS VISITING AYDER HOSPITAL TIGRAY ETHIOPIA

The frequency of ABO and Rhesus blood group vary geographically,ethnically and from one population to another. Some variation may occur with in one ethnic groups and within small country. This study was conducted to determine freqeuency of ABO and Rhesus blood group,phenotype, genotype,and allele among ethnic group Tigrean, Saho,and ,Erob people in Mekelle city Ayder Hospital Tigray, Ethiopia. A Total of 630 individuals were selected purposively among the patient of Ayder Hospital. These included 210 blood Samples were obtained from each of the three ethnic group. Blood Samples were collected by Open Slide test method within two months from January to March 2018. There were differences in frequency of ABO blood group alleles AB, and Rh-negative has lowest frequency in the three ethnic groups. It was observed that the frequency of allele IO among the Tigrean, Saho and Erob ethnic groups were 0.6919, 0.6695, and 0.6521 respectively while the respective frequency of IA was 0.1836, 0.1809 and 0.1870. Likewise allele IB had frequency of 0.1245, 0.1496, and 0.1609 ,the phenotypic frequency O 0.4762, 0.4429,and 0.4190,A 0.2905,0.2809, and 0.2857,B 0.1905, 0.2286 and,0.2429 AB, 0.0428, 0.0476 and ,0.0524 Among Tigrean, Saho and Erob ethnic groups while the corresponding frequency of Rh d allele was 0.2182,0.6473 and 0.2672 for the same ethnic groups, respectively. The distribution and proportion of individuals belonging to each ethnic group did not differ significantly from those expected under the Hardy Weinberg law (p value> 95 %).people respectively. Over all, among the three ethnic groups studied 93.8 % were Rh positive and 6.19 % were Rh negative. The frequency of Rh D allele was 0.7818, 0.7419 and 0.7328, respectively for the Tigrean, Saho and Erob