Abstract:
The ABO and Rh blood groups are the most important blood groups despite the long list
of several other blood groups discovered so far. The ABO and Rh blood groups varies
worldwide and are not found in equal numbers even among ethnic groups. Therefore, the
objective of the study was to estimate phenotypic, genotypic and allelic frequencies of
ABO and Rh blood groups among students of Oromo, Amhara and Gurage ethnic groups
in Geresu Duki preparatory school in Woliso town, Oromia, Ethiopia. The study was
conducted on 470 (48%) out of 985 students in Geresu Duki preparatory school who
were enrolled in 2016/17. These were purposively selected and the sample were divided
into three ethnic groups, Oromo ,Amhara and Gurage and stratified along ethnic lines.
The frequencies of ABO and Rh(D) blood group phenotypes were determined and
Hardy-Weinberg Law was used to determine allelic and genotypic frequencies. In the
overall sample, the O, A, B, and AB blood group percentages were 40%, 30.64%, 21.70%
and 7.66%, respectively. The most prevalent blood group was type O followed by A, B,
and AB. Blood group O had the highest frequency while blood group AB had the least
distribution. The Rhesus positive frequency was 96.38%, while Rhesus negative was
3.62% in the overall sample. The order of ABO blood group allele frequencies was IO>
I
A> IB in the overall samples and in each of the three ethnic groups. The overall allelic
frequencies of the population as they were calculated using the extension of the Hardy–
Weinberg law were 0.63, 0.21 and 0.16 for IO
, IA
and IB
alleles, respectively. Also on the
Rhesus status, the allelic frequencies were 0.81 and 0.19 for D and d alleles, respectively.The Chi-square test was done to compare observed phenotypic frequency distribution of
ABO and Rh (D) blood groups with that expected .Overall results from this study show
that phenotypic, genotypic and allelic frequencies of ABO and Rh blood group were
varied in different ethnic groups.
