Question

Which of the following phenotypes would most likely be the result of a Hox gene mutation?

a. abnormal body length or height

b. two different eye colours

c. the contraction of a genetic illness

d. two fewer appendages than normal

Short answer

Hox gene is a class of transcriptional control genes which determines the general body plan of an animal, including the number of body segments, the number and location of appendages, and the direction of the animal's head and tail.

Step-by-step solution

Step 1. Introduction 

Animals of all species share a large number of Hox genes, a class of transcriptional control genes. Hox genes act as "master control genes" that have the power to activate or inactivate a sizable number of other genes. By encoding transcription factors that regulate the expression of multiple other genes, hox genes do this.

Step 2. Explanation for the correct option

The correct option will be d. two fewer appendages than normal.

The general body plan of an animal, including the number of body segments, the number and location of appendages, and the direction of the animal's head and tail, are all determined by this gene cluster.

Explanation for the incorrect options 

The Hox gene does not control the phenotypes such as body length, eye colour and genetic illness; therefore, any mutation in the Hox gene will not affect these phenotypes.