A male child receives an X chromosome from his mother and a Y chromosome from his father; females get an X chromosome from each parent.
Genes are sections or segments of DNA that are carried on the chromosomes and determine specific human characteristics, such as height or hair color.
And, each of the person's children will have a 1 in 2 (50%) chance of inheriting the gene and developing the same features.
Diseases and conditions caused by a dominant gene include achondroplasia (pronounced: ay-kon-druh-PLAY-zhuh, a form of dwarfism), Marfan syndrome (a connective tissue disorder), and Huntington disease (a degenerative disease of the nervous system).
Can your genes determine whether you'll be a straight-A student or a great athlete?
Heredity plays an important role, but your environment (including things like the foods you eat and the people you interact with) also influences your abilities and interests.DNA is wrapped together to form structures called chromosomes.Most cells in the human body have 23 pairs of chromosomes, making a total of 46.DNA contains four chemicals (adenine, thymine, cytosine, and guanine — called A, T, C, and G for short) that are strung in patterns on extremely thin, coiled strands in the cell. Cells are tiny — invisible to the naked eye — and each cell in your body contains about 6 feet of DNA thread, for a total of about 3 billion miles of DNA inside you! Genes are made of DNA, and different patterns of A, T, G, and C code for the instructions for making things your body needs to function (like the enzymes to digest food or the pigment that gives your eyes their color).As your cells duplicate, they pass this genetic information to the new cells.If the gene mutation exists in egg or sperm cells, children can inherit the gene mutation from their parents.When the mutation is in every cell of the body (meaning a child was born with it), the body is not able to "repair" the gene change.A person can be born with gene mutations, or they can happen over a lifetime.Mutations can occur when cells are aging or have been exposed to certain chemicals or radiation.Researchers have identified more than 4,000 diseases that are caused by mutations.But having a genetic mutation that may cause a disease or condition doesn't always mean that a person will actually develop that disease or condition.