Monday, June 18, 2012

Common Genetic Disorders

Inherited Disorders:
Autosomal dominant
  • Progeria: characterized by rapid aging
  • Huntington disease: characterized by involuntary arms and legs movements. Other symptoms include mild irritability and memory loss

Autosomal recessive
  • Tay-Sachs Disease:  They lack a certain enzyme that would allow cells to digest lipids. This causes the lipids to build up in the brain cells and destroy, which further causes blindness, mental deterioration, and death
  • Phenylketonuria: If untreated, children can be severely mentally handicapped
  • Albinism: Lacks the brown pigment melanin

X-linked recessive
  • Hemophilia: Reduced ability to clot blood.
  • Colour blindness: Cannot distinguish between colours
  • Duchenne muscular distrophy: Muscles waste away because the muscle cells are are engorged with fat and connective tissue

  • Sickle Cell Anemia: RBCs are shaped like sickles, causing reduced blood flow to various parts of the body.

Incomplete Dominance
  • Hypercholesterolemia: high cholesterol, so higher chances of heart attack

Aneuploidy (Non disunction):
Down syndrome: trisomy of the 21st chromosome
Edwards syndrome: trisomy of the 13th chromosome
Patau's syndrome: trisomy of the 18th chromosome

Turner's syndrome: only one "x" chromosome
Kinefelter's syndrome: "XXY"
Jacob's syndrome: "XYY"