Mutations of Regulatory Elements of Developmental Genes May Have Either

Multiple Choice

Mutations of regulatory elements of developmental genes may have either dominant or recessive effects. If a mutation deletes a silencer upstream of a HOX gene, which do you expect?

A) a dominant trans effect on both alleles of the HOX gene
B) a dominant effect in which cis HOX gene activity is up- regulated
C) a dominant effect which down- regulates HOX gene activity
D) a recessive effect in which cis HOX genes are down- regulated
E) a recessive effect in which cis HOX genes are up- regulated