Question

If one-half of the normal gene dose is enough to provide a wild-type level of function, then that gene is considered to be ________ .

A) dominant
B) recessive
C) gain of function
D) haploinsufficient
E) haplosufficient

Answer 1

A gene is considered haplosufficient if one copy of the normal gene is enough for wild-type function. Haplosufficiency allows a single wild-type allele to mask the effects of a recessive allele, which would only show a phenotype if in a homozygous recessive state.

Step-by-step explanation:

If one-half of the normal gene dose is enough to provide a wild-type level of function, then that gene is considered to be haplosufficient.

In genetics, haplosufficiency refers to a situation where a single copy of a wild-type allele provides sufficient function to maintain a normal phenotype, thereby masking the potential effects of a recessive allele on the other chromosome. This contrasts with haploinsufficiency, where a single copy of a gene is not adequate to achieve a wild-type phenotype, leading to an observable condition or disorder.

Dominant alleles typically produce sufficient protein such that one allele can effectively dictate the phenotype, while recessive alleles typically do not produce a functional protein, or they produce a protein at levels that are too low to affect the phenotype unless present in two copies (homozygous recessive).