ABO Blood Groups are efficient in delineating relationships across linguistic subpopulations of Pakistan
Objective: Variances in ABO blood groups frequencies across world populations make them valuable markers for studying population genetics. In this study, phenotype and gene frequencies of ABO blood group were investigated to delineate relationships across major linguistic subpopulations of Pakistan.
Materials and Methods: This is a prospective multiple cohort study design conducted during 2009-2014. Karachi with population from diverse linguistic and ethnic backgrounds was chosen as the study area. Cohorts were formed on the basis of mother tongue and termed as linguistic subpopulations. There were five major cohorts namely Balochi, Punjabi, Pashto, Sindhi and Urdu. Blood samples were collected from 2,327 unrelated individuals through random sampling within each cohort. ABO blood groups were determined using antisera. ABO gene frequencies were estimated through Bernstein methods. Cluster and Correspondence analyses were performed to explore relationships between linguistic subpopulations.
Results: Gene B was the most common across all the subpopulations except Balochi subpopulation that showed relatively higher frequency of gene A. Dendrogram of cluster analysis and biplot of correspondence analysis showed closeness of three subpopulations namely Punjabi, Sindhi and Urdu.
Conclusions: Apart from describing the frequencies of ABO blood groups, this study asserts the importance of ABO blood group in delineating the relationships between the subpopulations of Pakistan. ABO blood group has long been used as identification markers in medico-legal investigation. It is interesting to know that these markers are also efficient in delineating population genealogical structure. Randomization within a cohort, un-relatedness and a larger sample size enhance the reliability of the results.