Mapping of Amy (Amy₁/Amy₂), Duffy and 1qh by family studies

Using maximum likelihood, methods were developed to simultaneously analyze triple heterozygotes with double heterozygotes, to include information not utilized in previous human linkage analyses. Analysis of informative families provided estimates for: likelihood of 3 point linkage, odds for each order, corresponding recombination fractions (R), and interference. For Amy:Fy the maximum lod score equals 5.20 at R=0.20 for males and 0.25 at R =0.34 for females; for Amy:1 qh, 2.87 at R=0.07 for males and 0.12 at R= 0.40 for females; for 1 qh:Fy, 2.67 at R=0.14 for males and 3.16 at R= 0.14 for females. The maximum lod for 3 point linkage from male and combined sex data varies from 8.1 to 10.7; however 3 point linkage is not directly established in females. The most likely order of the loci from male data is Amy 1 qh Fy which is the second most likely order for female and combined sex data. The relationships of Amy and Fy to PGM₁ suggest that the Amy loci are located on 1p and Fy on 1q.