Why is the 9:3:3:1 ratio for dihybrid crosses constantly referred to as the “phenotypic ratio”?
Shouldn’t it be the “genotypic ratio” because different genotypes often result in the same phenotype - thanks to simple dominance? :dubious::dubious::dubious:
Let’s cross AaBb and AaBb. A and B both exhibit simple dominance.
The number of resulting unique phenotypes is 4 - not 17 (as implied by 9+3+3+1).
However, the number of resulting unique genotypes is 17. :eek: