Lecture 6

Question 0

What is incomplete penetrance?

Answer 0

Individual who has the gene for a disease but does not express the disease.

Question 1

What are the characteristics of an autosomal dominant disorder?

Answer 1

Abnormal allele is dominant, normal allele is recessive and the genes exist on a pair of autosomes. Equal between gender, no generation skipping.

Question 2

What is age dependent penetrance?

Answer 2

Symptoms not appearing until later on in life (40-60yrs)

Question 3

What are characteristics of autosomal recessive disorders?

Answer 3

Abnormal allele is recessive and a person must be homozygous for the abnormal allele to express the disease.

Question 4

What is the most common inherited metabolic disorder?

Answer 4

Phenylketonuria (PKU)

Question 5

What are characteristics of sex linked disorders?

Answer 5

Disorders that involve X and Y chromosomes. X linked disorders expressed by males, females have another X to mask abnormal allele.

Question 6

In X-linked recessive disorders, who is most affected and how does the gene transmit?

Answer 6

Males most commonly affected, males cannot transmit gene to son but can to daughters. Sons of female carries have 50% chance of inheriting disorder.