If we cross Surface fish (have eyes and are not albino) with fish from Cave Scarlet, the F1 progeny have eyes and are not albino. If we backcross these F1 Surface/Scarlet hybrids to Scarlet cavefish, 50% of the progeny are albino and 50% are not albino. In terms of the eye phenotype, there is a broad range of eye phenotypes extending from no eyes like the original Scarlet population to complete eyes like surface fish (with varying degrees of eye formation in between

More than one gene is controlling the loss train of that eye. Thus, the Cross among the scarlet and grey species, F1 crossover has fractional eyes. Despite the fact that both sort of cavern fishes are visually impaired, yet cross between them has brought about offspring with fractional eyes. This shows multi-gene legacy for eye misfortune attribute. Blending of two genotypes has brought about incomplete characteristic in the descendants.

i think it is dna, i'm not totally sure but i think it might be.

this is math not biology xd