Genetic Disorders and Chromosomal Abnormalities

Cystic Fibrosis

• Recessive Condition

  • Mutation of the gene for the protein CFTR

  • CFTR regulates sodium levels across cell membranes

  • Causes respiratory problems

Tay Sachs

• Recessive condition

  • Mutation of a gene for a lipid-processing enzyme

  • Abnormal lipids accumulate in the brain

  • Causes severe mental decline and death by age 4

PKU

• Recessive condition

  • Mutation of the gene that produces phenylalanine hydroxylase

  • Causes progressive mental decline

Sickle Cell Anemia

• Recessive condition

  • Mutation of the gene that creates hemoglobin

  • Causes the blood cell to form into sickles 

  • Causes anemia and clotting

Huntington’s Disease

• Dominant condition

  • A single defective gene for a protein called huntingtin located on chromosome 4

  • Defective huntingtin protein leads to brain changes that cause abnormal involuntary movements, a severe decline in thinking and reasoning skills, and irritability, depression and other mood changes.

Down’s Syndrome (Trisomy 21)

Extra copy of chromosome 21

Turner’s Syndrome (XO)

Affected female is missing an X chromosome. Short, slow growth, heart problems, infertility

Klinefelter’s Syndrome (XXY)

Extra X chromosome in males. Low testosterone levels, underdeveloped muscles, sparse facial hair