Phenotyping of Rh, Kell, Duffy and Kidd blood group antigens among non-tribal and tribal population of South Gujarat and its implication in preventing alloimmunisations in multitransfused patients.

Background:Sickle cell anaemia is common amongst Tribal population of south Gujrat. Alloimmunisation in multitransfused sickle cell anaemia patient is 10 times commoner in these patients than beta Thalassemia  major  patients from regular blood donor communities.Study design u0026 methodology: Red cell antigen typing of Rh (D,C,E,c,e ), Kell (K, k), Duffy (Fya, Fyb) and Kidd (Jka, Jkb) were carried out in 222 regular voluntary blood donors who belonged to non-tribal population and in 113 samples of tribal population using conventional antisera. Results: Rh D antigen frequency was 96.6% in non-tribal and 96.5% in tribal population. 2.4% of K antigen was found in non-tribal population whereas the antigen was absent in tribal population  .Amongst Rh antigens, e was the most common (100%) followed by D, C (91.0%, 85.8%), c (50.5%, 44.2%) and E (16.5%, 17.0%) with DCe/DCe (R1R1, 48.0%, 55.8%) being the most common phenotype in both the groups. In Kell antigens  k antigen was 100% ,Kidd and Duffy antigens  Jk (a+b-) (39.2%, 46.9%) and Fy (a+b-) (64.2%, 52.2%) were the most common phenotypes in non-tribal and tribal population respectively. Conclusion: There is significant difference in Duffy , Kidd and Kell (k) antigen distribution between non tribal and tribal population . Total absence of Kell antigen in tribalsalong with. E antigen in a significant portion of blood donors and its absence in large number of tribals also increase the risk of alloimmunisation.