Potential alleles are those pairs of genetic variants that can produce offspring due to a compensatory mutation. Based on the material of four loci (hemoglobins 1, hypoxic hypoxia 2, sickle cell anemia 3, fructosamine 4), it was shown that they can replace the normal form with another form due to inverter genes and complementary genes, the latter of which involve mutations of the same genes for different types of complementation. Thus, these representatives are not simply minor mutants in the sense that their disappearance from the population has little disruption