I am asked to fill the genotypes in the spaces provided but looks like I am aving a little bit of trouble. can anyone help? thanks in advance!
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Here are a few hints that might help:
Talking about Maria's pedigree: Firstly, it seems as if you have mixed up with $X^a$ and $X^A$, see that the disorder is X-linked DOMINANT. Anyone with either heterozygous or homozygous dominant expression would have the disease expressed. So the first generation male should have a genotype: $X^aY$, because if it were $X^AY$ then Amelogenesis imperfecta would be expressed as his phenotype and the first generation female should have a homozygous recessive genotype. Also no child in the second generation would suffer from the same. (NOTE: The one suffering from Amelogenesis in the second generation would have genotype $X^AY$)
As for Gunther disease, both the parent in the first generation should have a heterozygous dominant expression and the offspring suffering must have a homozygous recessive expression. And you can apply the same basics in Peter's pedigree.
I think this much should be enough to complete the task, but if you still have some doubt you can put it forward in the comments.