In cattle coats may be sold white, solid black or black and white spotted. When

Question

In cattle coats may be sold white, solid black or black and white spotted. When true breeding solid whites are mated with true breeding solid blacks, the F1 generation consists of solid white individuals. Following many matings of F1 X F1 individuals these phenotypes were observed. 123 solid white 28 black and white spotted 11 black explain the mode of inheritance of coat color and pattern and define which genotype results in a particular phenotype. Is it possible to produce true breeding black and white cattle?

Explanation / Answer

Let the gene for white (1st locus) be W i.e. ww = recessive Let the alleles for the 2nd locus be B and b. White: W_B_, W_bb Black&White: wwB_ Black: wwbb This is dominant epistasis, where the dominant allele of the 1st locus (W) masks the expression of the 2nd locus. When the two alleles in the 1st locus are recessive (ww), the alleles in the 2nd locus can be expressed(B and b). Edit: In the second locus, the presence of a dominant allele (B) results in black-and-white spotted offspring, while two recessive alleles (bb) result in pure black offspring. I don't know how to answer your second question but I don't think it's possible. A true-breeding strain would have the genotype wwBB, but to get it is only possible if you knew the genotype of the parents and isolate the offspring with the genotype wwBB and breed from there.

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.