Question

A mutation in a regulatory sequence that allows the gene to be expressed in a new tissue, or at a new time (in addition to its normal expression) is likely to be considered a _______ mutation, and would likely be _______ relative to the wild type allele of the same gene.

A) gain of function; dominant
B) loss of function; recessive
C) hypomorphic; dominant
D) amorphic; recessive
E) both B and D are correct

Answer 1

A gain-of-function mutation causing gene expression in new tissue or time is dominant relative to the wild type allele. Therefore, the most appropriate correct option is A.

Step-by-step explanation:

A mutation in a regulatory sequence that leads to the expression of a gene in new tissue or at a new time, in addition to its normal expression, is likely to be a gain-of-function mutation, and would likely be dominant relative to the wild type allele of the same gene. The correct answer to this question is A) gain of function; dominant. Gain-of-function mutations can result in a gene product with an enhanced, new, or constitutive (constant) activity. Such mutations are often dominant because even in the presence of a normal allele, the mutated gene's action can be dominant to the product of the normal allele. This is seen in cases like oncogenes, where the presence of the mutant protein can lead to an altered phenotype.