Partial phenotyping in voluntary blood donors of Gujarat State

INTRODUCTION: Partial phenotyping of voluntary blood donors has vital role in transfusion practice, population genetic study and in resolving legal issues. The Rh blood group is one of the most complex and highly immunogenic blood group known in humans. The Kell system, discovered in 1946, is the third most potent system at triggering hemolytic transfusion reactions and consists of 25 highly immunogenic antigens. Knowledge of Rh & Kell phenotypes in given population is relevant for better planning and management of blood bank; the main goal is to find compatible blood for patients needing multiple blood transfusions. The aim of this study was to evaluate the frequency of Rh & Kell phenotype of voluntary donors in Gujarat state. MATERIALS AND METHODS: The present study was conducted by taking 5670 samples from random voluntary blood donors coming in blood donation camp. Written consent was taken for donor phenotyping. The antigen typing of donors was performed by Qwalys-3(manufacturer: Diagast) by using electromagnetic technology on Duolys plates. RESULTS: Out of 5670 donors, the most common Rh antigen observed in the study population was e (99.07%) followed by D (95.40%), C (88.77%), c (55.89%) and E (17.88%). The frequency of the Kell antigen (K) was 1.78 %. DISCUSSION: The antigen frequencies among blood donors from Gujarat were compared with those published for other Indian populations. The frequency of D antigen in our study (95.4%) and north Indian donors (93.6) was significantly higher than in the Caucasians (85%) and lower than in the Chinese (99%). The frequencies of C, c and E antigens were dissimilar to other ethnic groups while the ‘e’ antigen was present in high frequency in our study as also in the other ethnic groups. Kell antigen (K) was found in only 101 (1.78 %) donors out of 5670. Frequency of Kell antigen in Caucasian and Black populations is 9% & 2% respectively. The most common Kell phenotype was K-k+, not just in Indians (96.5%) but also in Caucasians (91%), Blacks (98%) and Chinese (100%). CONCLUSION: Phenotype and probable genotype showed wide range of variations in different races and religion. Reliable population based frequency data of Rh & Kell antigens has vital role in population genetic study, in resolving medico legal issues and in transfusion practice.