the presence of two copies of a mutated or defective gene (homozygosity) is required for an individual.

aka christmas disease deficit of clotting factor 9

Giant gene is a frequent target for mutations

Some ________ are due to the interacting effects of several individual genes.

When two people carrying a recessive mutation in the same gene have children, ________ of the children will inherit both mutant copies and exhibit the disease.

Its frequency is rare

Defective ion transport indirectly affects mucous secretion in lungs

- lack of enzyme causes immune deficiency

is a genetic disorder that occurs when an individual has an extra copy of chromosome 21

A _____ mutation usually occurs in only one copy of a gene.

Detected in newborns by urine analysis Special diet prevents symptoms

the defective protein may bind to and interfere with the normal protein and the proteins function as ______

Common form of X-linked mental retardation

first defect approved for human gene therapy

- It affects 1/2000 (whites) - Rare in Asians

1/10,000 males (sex-linked)

Heterozygotes are resistant to malaria but homozygotes are sick

Genetically dominant form of dystrophy

1/400 (U.S. blacks)

refers to a condition where an individual has only one functional copy of the elastin gene (ELN) instead of the normal two copies.

caused by a mutation or abnormality in a gene located on the X chromosome.

-It refers to a medical condition or abnormality that is caused by changes or mutations in an individual's DNA.

It affects 1/3000 males (sex-linked)

If the mutant protein is defective but still forms dimers, then ______ of the complexes will be defective.

Defect in hemoglobin beta chain

People with one copy of ELN are unable to make sufficient elastin for this tissue, resulting in a narrowing of the aorta that sometimes requires surgery and is referred to as ________.

deficit of clotting factor 8

Disintegration of muscle tissue

Mental retardation due to lack of enzyme

1/1500 in males 1/3000 in females (sex-linked)

Common in Africa First molecular disease to be identified

1/5000 (Western Europe) Rare elsewhere

a single copy of a mutated or defective gene on one of the non-sex chromosomes.

occur when the defective copy of a gene interferes with the functional copy.

It affects 1/10,000

is a genetic condition in which a single functional copy of a particular gene is insufficient to maintain normal cellular function.

Defect in blood coagulation

Some examples are cleft palate, spina bifida, certain cancers, and diabetes.

is found in the elastic tissues of skin, lung, and blood vessels.

If the brother and sister have offspring, their child may inherit ______ copies of the defective gene and then exhibit the symptoms of the defect.