Chapter 3

Question 1

Sickle Cell Anemia

Answer 1

The most common genetic disease among people of African ancestry. Sickle-cell hemoglobin forms rigid crystals that distort and disrupt red blood cells; oxygen-carrying capacity of the blood is diminished.

Question 2

Cystic Fibrosis

Answer 2

The most common genetic disease among people of European ancestry. Production of thick mucus clogs in the bronchial tree and pancreatic ducts. Most severe effects are chronic respiratory infections and pulmonary failure.

Question 3

Tay-Saches Disease

Answer 3

The most common genetic disease among people of Jewish ancestry. Degeneration of neurons and nervous system results in death by the age of 2 years.

Question 4

Phenylketonuria

Answer 4

Lack of an enzyme to metabolize the amino acid phenylalanine leads to severe mental and physical retardation. These effects may be prevented by the use of a diet (beginning at birth) that limits phenylalanine.

Question 5

Hungtington’s Disease

Answer 5

Uncontrolled muscle contractions between the ages of 30 and 50 years, followed by a loss of memory and personality. There is no treatment that can delay mental deterioration.

Question 6

Hemophilia (X-linked)

Answer 6

Lack of factor VIII impairs chemical clotting; may be controlled with factor VIII from donated blood.

Question 7

Duchenne’s Muscular Dystrophy (X-linked)

Answer 7

Replacement of muscle by adipose or scar tissue, with progressive loss of muscle function; often fatal before age 20 years due to involvement of cardiac muscle

Question 8

Genomic Medicine

Answer 8

An emerging medical discipline that involves using genomic information about an individual as part of their clinical care and the health outcomes and policy implications of that clinical use.

Question 9

What are the 3 types of genetic testing?

Answer 9

Carrier testing
Preimplantation
Prenatal
Newborn screening

Question 10

Carrier Testing

Answer 10

Used to identify individuals who carry one copy of a gene mutation when there is a family history of a genetic disorder. When both prospective parents are tested, the test can provide information about their risks of having a child with a genetic condition.

Question 11

Preimplantation Testing

Answer 11

Preimplanation genetic diagnosis, is used to detect genetic changes in embryo created using assisted reproductive techniques. Prior to transferring an in vitro embryo into the woman’s uterus, a cell from the developing fetus is removed for genetic testing.

Question 12

Prenatal Testing

Answer 12

Allows for the early detection of genetic disorder such as trisomy 21, hemophilia, and Tay-Sachs disease.

Question 13

Newborn Screening

Answer 13

Used to detect genetic disorder that can be treated early in life.