Linkage data on aminolevulinate dehydratase (ALADH, E.C. 4.2.1.24) and a series of other human genetic markers are presented. One hundred and two families (25 of them being informative) from southwestern Germany were tested. Close linkage (
=0.05) between ALADH and the following markers could be excluded: Rh, PGM
1, Fy, ACP1, MNSs, HLA, Bf, GLO, PGM
3, Jk, Pi, PGP, K, GPT. There is some evidence of possible linkage with HPA.