Frequency of partial D in Western India.

Partial D is of clinical importance as the partial D-positive individuals who lack some epitopes of D antigen can develop anti-D if exposed to normal D antigen. The frequency of partial D varies in different populations. The majority of molecular studies on D variants have been reported in European, African and some East Asian populations, but no study has been reported in the Indian population so far. The aim of the study was to screen Indian population for detection of partial D by serology and classify them by multiplex polymerase chain reaction (M-PCR). The study population, consisting of 10,000 RhD-positive individuals from West India, was screened for detection of partial D using the partial D kit. In addition to these, blood samples referred because of serological RhD discrepant results from blood banks of West India were also investigated. The samples identified as partial D from these two groups were further characterized by M-PCR. Fifteen partial D cases were identified by population screening and 45 were identified from referred samples. Population screening revealed that one third of partial D was DFR when tested by partial D kit. We were able to classify 63.4 and 76.6% of partial D by partial D kit and M-PCR, respectively. The incidence of partial D in West India was found to be at least 0.15% when tested with partial D kit. DFR partial D was found to be predominant in the present study.