Ban I RFLP for the identification of FY*A and FY*B alleles in non-Ashkenazi Jews. DNA was amplified using FY3 and FY4 primers for the amplification of a DARC fragment containing the 131G → A substitution, responsible for FY*A and FY*B, respectively. Restriction fragments were separated on 1% agarose gel. (A) Schematic diagram of fragments generated by the Ban I digestion of FY*A and FY*B DNA. (B) RFLP patterns of DNA from samples with the indicated phenotypes, identified by antisera (the 52- and 44-bp fragments are not detected in this gel). Lanes: 1, 100-bp ladder; 2, uncut; 3, 4, 6, 7, and 9, Fy (a+b−); 5, 8, and 10, Fy(a−b−).