Genetic Disorders

Genetic Disorders: A genetic disorder results from an inherited

disruption in an organism’s DNA Can be a change in the number of

chromosomes and deletion or duplication of entire chromosome or part of chromosome

Disorders can be linked to a change in a single specific gene

Cystic Fibrosis (CF) Recessive disorder 1 in 2500 births 5% of pop. are carriers

Phenylketonuria (PKU) Recessive disorder 1 in 10,000 births Inheritance of genetic

mutation Leads to mental

retardation

and epilepsy if not treated

Down Syndrome Faulty gamete cell division Small % inherit

chromosomal

defect from mother or father

Excess of chromosome 21 Cause mental retardation,

hearing loss, heart defects

Tay Sachs Disease 2 Tay sach carriers

have 1 in 4 chance of passing on disease

Fatal inherited disease

Affects buildup of fatty substances in brain and nerve cells

Sickle Cell Anemia Heredity disease 1 in 12 African

Americans carry sickle cell traits

Red blood cells become rigid and curved

Can cause anemia

Hemophilia Bleeding and clotting

disorder Sex-linked disorder –

about 1 in 4,000 males are born with disorder each year

Have mutation in Factor VIII gene

Albinism Little or no pigment in

their eyes, skin, and hair

Affects about 1 in 17,000 births each year

Can occur in humans and animals

Dwarfism Usually refers to primary

bone disorder—bones do not grow and develop properly

Affects 1 in 40,000 children born each year

Commonly causes short limbs and bowed legs

Progeria Rare, fatal genetic

disorder Name comes from greek

meaning “prematurely old” Mutation in gene called

LMNA Children usually die of

heart disease by age 8-13 100 cases since 1886

Osteogenesis Imperfecta Literally means “bone that

is imperfectly made from the beginning of life”

Also called “brittle bone disease”

Most cases caused by dominant genetic defect or spontaneous mutation

1 in 20,000 births

Cleft Lip & Palate 1 in 700 children will

be born with a cleft-related birth defect

Most are boys If a person has a cleft

defect, there is a 50% possibility of passing gene to an offspring

Clubfoot One or both feet can

be affected Affects 1 out of every

100 births Risk factors: family

history of disorder and being male