Red cell genotyping for blood group SNPs. Outline of a method to determine blood group SNPs based on that of Karpasitou et al.⁸³  Many other methods are available (see also Hashmi et al,⁷⁴  Hillyer et al,⁷⁷  and Avent et al⁷⁸ ). This one is illustrated because it is suitable for “in-house” development.