Genetic and Congenital Disorders

Question 1

What is a genetic disorder?

Answer 1

A discreet event that affects gene expression in a group of cells related to each other by gene linkage.

Question 2

What is the difference between a genotype and a phenotype?

Answer 2

A genotype is a person’s genetic composition. A phenotype is the observable expression of the gene.

Question 3

Define “autosomal dominant”

Answer 3

Each child has a 50% chance of inheriting the disorder.

Question 4

What is an autosomal recessive gene?

Answer 4

The child needs two copies of the gene to be affected.

Question 5

What are the chances of a child being affected by an autosomal recessive gene?

Answer 5

Each child has a 25% chance of being affected, 25% chance of being unaffected, and 50% chance of being a carrier.

Question 6

What are the skeletal manifestations of Marfan Syndrome?

Answer 6

Long thin body, fingers. Hyperextensible joints. Kyphosis, scoliosis. Pectus excavatum.

Question 7

What are the ocular manitesfations of Marfan Syndrome?

Answer 7

Bilateral dislocation of lens (weak ligaments). Myopia with predisposition to retinal detachment.