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Sex-linked inheritance from heterogygous parents

In Pacific Pooch-Bellied Wrasses, belly color is controlled by a single gene located on the X chromosome (i.e. is sex linked), that can take one of four forms (alleles): Xy = yellow bellied, is dominant to all other alleles; Xb = blue bellied, and Xr = red bellied are incompletely dominant and produce purple-bellied fish when they occur together in a heterozygous combination.; Xw = white bellied, is a true recessive.

- a red-bellied male that had a yellow-bellied father mates with a blue-bellied female that had a purple-bellied mother and a blue-bellied father

a. What are the genotypes (for both belly color & gender) for the two individuals involved in this cross.

b. List and give the probable proportions of expected genotypes and phenotypes (for both belly color & gender of offspring from this cross.

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The only difference in solving a problem with sex-linked inheritance in non sex-linked is that males have only relevant chromosomes. Their other chromosome is a Y, which doesn't carry the gene. The X ...

Solution Summary

Possible genotypes and phenotypes resulting from the crossing of two heterozygous individuals when sex-linked inheritance occurs.