Minisequencing-based genotyping of Duffy and ABO blood groups for forensic purposes.

Duffy and ABO blood group genetic polymorphisms were studied by minisequencing analysis of single-nucleotide polymorphisms (SNPs) at nucleotide positions--33, 125, 265, and 298 of the Duffy gene and at nucleotide positions-261, 297, 467, 646, and 703 of the ABO gene. In an Italian population sample, we found four alleles and seven genotypes for the Duffy and six alleles and 16 genotypes for the ABO systems. The lower limit for reproducible results was 200 pg DNA, with a range of up to 10 ng and an optimum at 1 ng. All of the 16 analyzed inclusive paternity tests were also consistent with parentage and two out of four inconsistencies with parentage cases were excluded by one or more SNPs. Although Duffy and ABO SNP typing show lower informativeness than most current forensic tests, their robustness, the limited population distribution of FY* Fy type, and the sensitivity of the minisequencing technology suggest that these markers can be useful in selected forensic applications.