||Diego blood group Di(a-b+); found in > 99% of Caucasians and Blacks
||Diego blood group Di(a+b+); ancestors likely to include some East Asians/Mongolians and/or indigenous North/South Americans
||Diego blood group Di(a+b-); ancestors very likely to include some East Asians/Mongolians and/or indigenous North/South Americans
The Di(a)/Di(b) polymorphism of the Diego blood group antigen is due to a single amino acid substitution at position 854 of the band-3 protein, encoded by the SLC4A1 gene.[PMID 8206915]
Di(b) is common or ubiquitous to at least some extent in all populations which have been screened for it, while Di(a) has been found only in indigenous peoples of the Americas (in both North and South America) and East Asians, and in people with some ancestors from those groups.Wikipedia
The rs2285644(C) allele encodes a proline at this position, which corresponds to Di(b). The rs2285644(C;C) genotype results in the Diego phenotype Di(a-b+), found in over 99.9% of Caucasians and Blacks, and over 90% of Asians.
The rs2285644(T) allele encodes a leucine at this position, which corresponds to Di(a). As stated above, this is found primarily only those with East Asian (Di(a+b+) is found in 10% of Asians overall) or indigenous American (North or South) ancestors. Dia antigen is more commonly found in Oriental people of Mongolian descent, being more common in the Japanese (12%) and the Chinese (5%). In South American Indians, up to 54% of the population carries the Dia antigen. Therefore, the most common phenotype in most such populations is Di(a+b+).
[PMID 21257350] DNA-based methods in the immunohematology reference laboratory.
Non-ABO Blood Groups