Molecular Biology Test One

Single gene disorders are AKA Mendelian or monogenic disorders.
These disorders are the result of a single mutation.
Ex: Cystic fibrosis, sickle cell anemia, Marfan syndrome, and Huntington’s disease.

Caused by a combination of environmental factors and mutations in multiple genes.
Ex: Heart disease, high blood pressure, Alzheimer’s disease, arthritis, diabetes, cancer, and obesity.

Major chromosomal abnormalities (polyploidy or rearrangements).
Examples: Down's Syndrome (trisomy 21)

Caused by mutations in the nonchromosomal DNA of mitochondria.

Dealing with loci, two loci are said to be linked ifalleles at these loci recombine at <50%, in chromosomal/DNA language these loci are within a certain number of base pairs of each other on the same chromosome.

Dealing with alleles, two alleles are said tobe associated if their “phenotypes” always appear together. This is the principle behind “molecular diagnostics”, i.e., “genetic change” = “disease”. The ultimate association = 100%.