GN 301 Module 1: Introduction to Genetics

Genetics

a "coming into being "or "developing the self”. It is the study of heredity.

Where does the word Genetics come from?

Genesis or “to generate”

List several areas where Genetics is important in society:

* The news
* Medicine
* Epigenetics
* Agriculture
* Pest management
* DNA sequence analysis bioinformatics
* Gene editing and gene therapy

Allele

a form of a gene (there are two possible variations)

Phenotype

________: the actual appearance of an individual for a particular trait.

Genotype

________: the combination of alleles that an individual has for a given gene.

Homozygous

the two alleles for a given trait are the same

Heterozygous

the two alleles for a given trait are different

Dominant

an allele that is physically seen in a heterozygous individual.

Recessive

an allele that is not physically seen in a heterozygous individual.

Cystic Fibrosis

A recessive mutation that causes thick mucus to accumulate in the lungs, leading to respiratory infections and breathing difficulties.

* It occurs in a gene on Chromosome #7 and is common in those of European descent.
* Genetic testing is available.
* Gunnar Esiason is a famous example of someone who has the mutation.

Osteogenesis imperfecta

A dominant mutation with variable effects that may include

* multiple bone fractures
* decreased mobility

Xeroderma Pigmentosum

A recessive mutation that causes excessive sensitivity to UV light.

* Persons affected must have two alleles of the gene to have the disease.
* They can get many small tumors on their body that look like freckles but is actually skin cancer.

Gunnar Esiason

a famous example of someone who has Cystic Fibrosis

Marfan Syndrome

A dominant mutation that only requires one allele of the mutation to have it.

* People affected have long limbs.
* A famous person affected by the disorder was Flo Hyman, who died of heart complications.
* The disease weakens your aorta, which makes you bleed easily.

European descent

Cystic Fibrosis occurs in a gene on Chromosome 7 and is common in those of ________.

Flo Hyman

a famous person affected by Marfan Syndrome, who died of heart complications.

Sickle Cell Anemia

A recessive mutation where an individual’s blood cells are sickled instead of smooth and round.

* The blood cells get stuck in the capillaries.
* 2 mutated alleles are required for this genetic disorder, which is most common in people of African descent.

What descent of race is sickle cell anemia most common in?

African descent

karyotype

An organized array of a cell’s chromosomes.