Exam 18: Genetics of Behavior

Huntington disease involves multiple trinucleotide repeats of the nucleotide sequence _____________.

Alcoholism has been proposed as a genetically controlled or influenced trait. Outline some of the difficulties in studying the genetics of this behavior trait, beginning with the definition of the phenotype. Can you define the problem in such a way that will provide a hypothesis as to the nature of the disorder, allowing a genetic approach to be mounted?

Give evidence that might prove that human personality could be partially inherited.

Discuss the tools used to see if human behavior has a genetic component, and give two examples of either normal or abnormal behavior that appears to have a genetic component.

All behavioral traits have an early onset.

The mutant huntingtin protein that results in Huntington disease

What is the function of a normal MAOA protein?

Association studies compare affected individuals from different families with unaffected individuals, seeking to find genetic differences between those with and without a behavior disorder. Given the size and complexity of the human genome, do you think this approach can be used to systematically scan the genome for loci controlling behavior? How will you know when you have found one? How do you differentiate between polymorphisms and genuine differences?

A mutation in the MAOA gene is associated with ____________ behavior.

People carrying less than 35 CAG trinucleotide repeats are more likely to develop Huntington disease.

Huntington disease is