Consider a gene in mice that is normally maternally imprinted. If a deletion occurred in the gene, rendering it nonfunctional, what would be the expected phenotypic result?
A) If the mutation occurred in the maternal copy of the gene, the mouse would be wild-type, but if the mutation occurred in the paternal copy of the gene, the mouse would be mutant.
B) If the mutation occurred in the maternal copy of the gene, the mouse would be mutant, but if the mutation occurred in the paternal copy of the gene, the mouse would be wild type.
C) If the gene behaves in a dominant manner, the mouse would be mutant, but if the gene behaves in a recessive manner, the mouse would be wild type.
D) Because the gene is maternally imprinted, all female mice would be mutant, but all male mice would be wild type.
E) Because the gene is maternally imprinted, all female mice would be wild type, but all male mice would be mutant.

Question

Quizplus · Accepted Answer

In maternal imprinting, the maternal allele is silenced, and only the paternal allele is expressed. Therefore, if the mutation occurs in the maternal copy, it has no effect, and the mouse remains wild-type. If the mutation occurs in the paternal copy, the gene is nonfunctional, and the mouse would be mutant.

Consider a Gene in Mice That Is Normally Maternally Imprinted