Genetics of the GPT system. Family, mother/child and association studies.

GPT types are presented for 150 Norwegian matings, with 454 children, and 1703 Norwegian mother/child combinations. There were five exceptions to a simple codominant inheritance pattern, all believed to be due to a segregating Gpt-0-allele. Rare phenotypes were encountered in two of the families and in 11 of the mother/child combinations. Compiled family material and mother/child material are presented. No indication of association was found between GPT types and phenotypes within the ABO, Rh, MN, Hp, Gc, C3, PGM1, and ACP1 systems. There is a marked association between EBS-Ogna (epidermolysis bullosa simplex, type Ogna) affection and GPT phenotypes. This reflects the Gpt-EBS1 linkage phase. No evidence was found of association between GPT phenotypes and either nephrological diseases or PKU (phenylketonuria).