Autoimmune anti-D in an RhD-positive young infant: Learning from a rare case.

Background And Objectives: Anti-D is usually immune in nature and is formed in individuals lacking D antigen or having variants/altered D phenotypes. In the Indian population, 93.8% are RhD positive, and R R is the commonest Rh phenotype.

Overview of the serologic and molecular basis of D variants with a focus on D variants in the Indian population.

Complexities of D within the Rh blood group system have long been recognized, initially using basic serologic testing and, more recently, using advanced and sensitive typing reagents. Discrepancies may arise when an individual carries a D antigen showing altered D antigen expression. These D variants are clinically important, since they may lead to production of anti-D in the carrier and induce alloimmunization in D- recipients, making their correct identification imperative.

Algorithm development and diagnostic accuracy testing for non-invasive foetal RHD genotyping: an Indian experience.

Background: The discovery of the cell-free foetal DNA (cffDNA) circulating in the maternal plasma enabled prediction of foetal RHD thus eliminating the risks associated with invasive procedures. Non-invasive foetal RHD genotyping has now become the standard approach in developed countries for management of alloimmunised women and is also used for targeted antenatal prophylaxis in non-alloimmunised women.

Materials And Methods: cffDNA was extracted from the plasma of 217 RhD negative pregnant women at a gestational age of 10-34 weeks.

Molecular characterization of rare D--/D-- variants in individuals of Indian origin.

Background: Rh antigens are critical in haemolytic disease of the foetus and newborn (HDFN). The D-- phenotype is a rare blood group characterised by the lack of expression of C, c, E and e antigens at the surface of red blood cells because of mutations in both RHCE alleles inactivating the expression of a "normal" protein. The aim of the study was to determine the molecular basis of D-- individuals of Indian origin.