Discussion:
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.