Which statement best describes epistasis, as illustrated by Labrador coat color, where the E allele (extension) must be present to deposit pigment and ee results in yellow regardless of the B allele?

Which statement best describes epistasis, as illustrated by Labrador coat color, where the E allele (extension) must be present to deposit pigment and ee results in yellow regardless of the B allele?

• A. Epistasis occurs when two genes independently contribute additively to a phenotype.
• B. Epistasis is when one gene masks the effects of another; in Labradors, the E allele must be present to deposit pigment, and ee yields yellow regardless of B.
• C. Epistasis is when a gene affects multiple traits (pleiotropy).
• D. Epistasis is a mutation that occurs in germline cells.

Answer: (B)