Representative gel electrophoretograms showing PCR-ASP screening for subgroup alleles.

PCR-ASP amplification products for A and B subgroup alleles with the W1 (A) and W3 (B) primer mixes, respectively, as separated on 2% agarose gels. The W2 primer mix gel is not shown because it works according to the same principle and looks virtually identical to the W3 gel. Samples from individuals with the following weak A and B subgroup mutations are shown. (A) Lanes 1-2, donors with the A^w-2 (350G>C) allele; lanes 3-4, donors with theA^w-3 (203G>C) allele; lanes 5-6,A¹O1  andA²O^1v random donors; and lane 7, H₂O contamination control. (B) Lane 1,B^w-5 (539G>A) allele; lane 2,B^w-4 (548A>G); lane 3,B^w-3 (721C>T); lane 4,B^w-8 (863T>G); lane 5,B^w-2 (873C>G); lane 6,B^w-6 (1036A>G); lane 7,B^w-7 (1055G>A); lane 8,BO1  random donor; and lane 9, H₂O contamination control. M is the molecular size marker φX174RF DNAHaeIII (Life Technologies). Arrows indicate the size of DNA fragments in base pairs.