Human Genetics: Inheritance Patterns, Genetic Disorders, and Testing

10 Questions

What type of inheritance pattern requires both copies of the gene to be the same for the trait to be expressed?

Recessive inheritance

If a child inherits one blue-eyed gene and one brown-eyed gene, what color eyes will they have under the dominant inheritance pattern?

Brown eyes

What is the main requirement for a trait to be expressed in dominant inheritance?

At least one copy of the dominant allele is enough

Under which inheritance pattern does a 25% chance exist for a child to inherit two copies of a recessive gene and develop a disease if both parents are carriers of the gene?

Recessive inheritance

What type of allele is required to express a trait under dominant inheritance?

Dominant allele

What is the primary cause of genetic disorders?

Changes in the body's DNA

Which genetic disorder is characterized by a buildup of thick, sticky mucus in the lungs, pancreas, and other organs?

Cystic fibrosis

What is the purpose of carrier screening in genetic testing?

Identifying whether a person carries a gene mutation that could cause a genetic disorder in their offspring

What does hemochromatosis, a genetic disorder, cause the body to absorb too much of?

Iron

When is predictive testing typically used in genetic testing?

To determine an individual's risk for developing a genetic disorder

Study Notes

Inheritance Patterns

Autosomal recessive inheritance pattern requires both copies of the gene to be the same for the trait to be expressed.
In dominant inheritance, if a child inherits one blue-eyed gene and one brown-eyed gene, they will have brown eyes because the brown-eyed gene is dominant.

Dominant Inheritance

The main requirement for a trait to be expressed in dominant inheritance is that one copy of the dominant allele is present.
In dominant inheritance, one copy of the dominant allele is required to express a trait.

Autosomal Recessive Inheritance

In autosomal recessive inheritance, there is a 25% chance for a child to inherit two copies of a recessive gene and develop a disease if both parents are carriers of the gene.

Genetic Disorders

The primary cause of genetic disorders is mutations in genes.
Cystic fibrosis is a genetic disorder characterized by a buildup of thick, sticky mucus in the lungs, pancreas, and other organs.

Genetic Testing

The purpose of carrier screening in genetic testing is to identify individuals who carry a recessive gene and are at risk of passing it to their offspring.
Hemochromatosis, a genetic disorder, causes the body to absorb too much iron.
Predictive testing is typically used in genetic testing when there is a family history of a genetic disorder or when a person is at risk of developing a genetic disorder.