Chapter 11, Problem 3A

Summary Introduction

Introduction :

Huntington’s disease is agenetic disorder cause due to genetic mutations in a particular gene. This disorder affects the nervous system. The symptoms of this disorder include a gradual loss of brain function, uncontrollable movements, and emotionaldisturbances.

Answer to Problem 3A

Correct answer :

The correct answer is option (D) Huntington’s disease.

Explanation of Solution

Explanation/justification for the correct answer :

Option (D) is Huntington’s disease. It is an autosomal dominant genetic disorder which results from genetic mutations involving trinucleotide repeats of the  Huntington  gene.Thus, the correct answer is option (D).

The explanation for the incorrect answer :

Option (A) is albinism. It is a genetic disorder which caused due to defect in one of several genes that produce or distribute melanin. The defect causesceased melanin production, or a less production of melanin. The defective gene passes down from both parents to the child and leads to albinism. Thus, this is an incorrect option.

Option (B)is cystic fibrosis. It is one of the most common recessive genetic which affects the mucus-producing glands, digestive enzymes, and sweat glands.Thus, this is an incorrect answer.

Option (C) is Tay-Sachs disease. It is a recessive genetic disorder. Its gene is located on chromosome 15. It is often identified by a cherry-red spot on the back of the eye. Thus, this is an incorrect answer.