Biology genetics question

A cross between individuals with AB and ab phenotypes results in offspring with 50% Ab
phenotypes and 50% aB phenotypes. What is the genotype of parents with AB phenotype?
A) AABb for independent characters
B) AaBb for associated characters
C) AaBb for independent characters
D) AABb for associated characters
E) Aabb for associated characters

Hi! First we look at the children:

Aabb (dominant A, recessive B)
aa Bb (recessive a, dominant B)

since the recessive alleles, the parent with AB must be heterozygous when coupled with the aabb parent since one allele must come from each of the parents, so the genotype must be AaBb

Is the answer C? I’m not sure what they meant by associated/independent.

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associated = non mendeleian
expected pheno ratio from punett square AaBb x aabb is 1:1:1:1
but here we have 1:1 , since we don’t have the expected ratio, linked genes can explain this

for me it’s B)


That makes sense It was either B or C depending on the ratios thank you Juliette!!

idk what the answer is i was confused between b and c. Thank you for clearing my doubt :slight_smile: