FREQUENCY OF ABO AND Rh BLOOD GROUP ALLELES AND GENOTYPES AMONG STUDENTS OF ARSI UNIVERSITY BELONGING TO AMHARA, OROMO AND TIGRAY ETHNIC GROUPS

The ABO and Rh blood groups frequency varies worldwide and are not found in equal frequency even among same ethnic groups. Therefore, this study was aimed at determining the frequency of ABO and Rh blood groups among Students of Arsi University, Oromia Region, Ethiopia. A total of 423 volunteer students were participated in the study. The students were divided into 3 ethnic groups, Amhara 141, Oromo 141 and Tigray 141 students. And participants were selected purposefully through cross-sectional survey. Blood samples were collected by Open Slide test method. A drop of each of the antisera; anti- A, anti -B and anti- D was added and mixed with each blood sample and rocked gently for 60 sec to observe agglutination. As a result, different frequency distribution of the ABO blood groups were recorded for the 3 ethnic groups. In Amhara ethnic group, the frequency showed A (0.3262), B (0.2624), AB (0.0496) and O (0.3617). In Oromo ethnic group, the frequency was A (0.3122), B (0.2482), AB (0.0354) and O (0.4042) while in Tigray students the frequency showed A (0.2762), B (0.2131), AB (0.0284) and O (0.4824). The most prevalent blood group was type O in all the 3 ethnic groups. The frequency distribution of Rh+ blood group in Amhara, Oromo and Tigray ethnic groups were obtained as (0.9433), (0.9291) and (0.9504) respectively; and the frequency of Rhblood group was (0.0567), (0.0709) and 0.0496) in Amhara, Oromo and Tigray ethnic groups respectively. The Chi square value of Rh for the Amhara, Oromo and Tigray ethnic groups were 4.4x10-7 , 4.4x10-6 and 3.5x10-7 respectively. The distribution of the overall observed frequencies of ABO blood group phenotypes do not differ significantly from those expected under Hardy-Weinberg equilibrium (Goodness of fit X2 = 2.7x10-7 , df = 3, p > 0.05