Mwo I RFLP for the identification of the 304G → A mutation. DNA was amplified using the FY3 and FY4 primers. Restriction fragments were separated on 1% agarose gel. (A) Schematic diagram of fragments generated by Mwo I digestion of the DARC fragment encompassing nt 304. (B) RFLP patterns of DNA from samples with the indicated phenotypes, identified by antisera, and genotypes, determined by Ban I and Sty I (FY*B = wild-type GATA; FY*B− = GATA mutation). Lanes: 1 and 2, Fy(a+b−)FY*A/FY*B; 3 and 8, Fy(a−b−)FY*B/FY*B−; 4 and 5, Fy(a+b−)FY*A/FY*B−; 6 and 7, Fy (a−b−) FY*B−/FY*B−.