PATHOLOGY

Detailed explanation-1: -Huntington’s disease is a progressive brain disorder caused by a single defective gene on chromosome 4-one of the 23 human chromosomes that carry a person’s entire genetic code. This defect is “dominant, ‘’ meaning that anyone who inherits it from a parent with Huntington’s will eventually develop the disease.

Detailed explanation-2: -Huntington’s disease is autosomal dominant, meaning inheritance of just a single copy of an abnormal chromosome from a biological parent is enough to cause it. If one parent carries the abnormal gene, each of their biological children has a 50 percent chance of Huntington’s disease inheritance.

Detailed explanation-3: -Huntington’s disease is caused by an inherited difference in a single gene. Huntington’s disease is an autosomal dominant disorder, which means that a person needs only one copy of the nontypical gene to develop the disorder.

Detailed explanation-4: -97% of Huntington’s disease suffers have inherited the mutant gene. Due to the dominance of the mutant allele (H) if one parent is heterozygous for the huntingtin gene (Hh) and therefore is affect by the disease each child has 50% chance of inheriting the disease, as shown in this punnet square.