An early theory of Rhesus blood group inheritance was that of the American Dr. Alexander Wiener.
Wiener's theory is that Rh inheritance is controlled as follows:
- There is one Rh locus at which occurs one Rh gene, but this gene has multiple alleles.
For example, one gene R1 produces one agglutinogen (antigen) Rh1 which is composed of three "factors": rh', Rh(o), and hr.
The three factors are analogous to C, D, and e respectively in the Fisher-Race nomenclature. Alleles of the one gene could be R2 (cDE in Fisher-Race), Ro (cDe in Fisher-Race), etc. The d gene does not exist in Wiener's theory.
Note: The main difference between the Fisher-Race and Wiener theories is that whereas the Fisher-Race theory has three closely linked loci, the Wiener theory has only one gene locus at which multiple alleles occur.