Problem
In a species of tropical frogs, the wild-type skin colour is grey-green, but a mutation in the Tdstk gene (T1 allele) results in a dominant phenotype of bright yellow skin. T1/T1 embryos do not survive (they fail to hatch) and this condition is considered recessive lethal.
What is the genotype of the frogs in the population that are bright yellow? How can this allele (T1) contribute to both a dominant phenotype and a recessive phenotype? Explain.