There are 2 types of test for genetic assessment. Screening and diagnostic.

If the genes differ, the person is said to be "homozygous" for that trait.

Allele codes for a specific gene

Sickle cell anemia occurs commonly among South African descent.

Phenotype is the outward expression of genes.

Humans have 23 pairs of chromosomes. 22 Autosomes and 1 sex chromosome.

Father with an x-linked condition will not have sons that will inherit the condition but daughters will be carriers.

A mother with x-linked disorder will have 50% of her sons having the disorder and 50% of her daughters as carriers.

In autosomal dominant disorder only a single diseased gene is needed to manifest the disease.

In autosomal recessive disorder 2 diseased genes is needed for the offspring to have the disease.

Genetic disorders can happen during the meiotic division phase of the gametes (ovum and sperm).

Genes are the basic units of heredity that determine both the physical and cognitive characteristics of people.

A person who has two like genes for a trait is said to be heterozygous.

The majority of X-linked inherited disorders are dominant.