What phenomenon occurs when a particular allele will either be expressed or silenced

Genomic imprinting

Explanation:

Complete Question

What phenomenon occurs when a particular allele will either be expressed or silenced, depending on whether it is inherited from a male or a female?

Solution -

Genomic imprinting of a gene depends on the sex of the person from which the gene is inherited. For instance, in some cases genes are imprinted (or become inactive) only when they are inherited from a particular sex of the parents let say male. However, if these genes are inherited form female parent, they remain active.

Genomic imprinting does not affect the DNA sequence in fact it changes the chromatin structure or changes the DNA structure chemically. For example - in Prader-Willi syndrome, gene on chromosome 15 is not expressed when it is inherited from the mother