BIOLOGY 1A03 Chapter 15: Genetic Variation

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Rosa Da Silva

Document Summary

Tandem repeats: repeated nucleotide sequences which are several thousand nucleotides long. They can be placed together in identical or near identical copies. Simple sequence: usually short (two nucleotides) which are repeated in a dna molecule. Variation does not always have an observed effect, especially if it is on non-coding regions. These variations can go unobserved, some are less serious, but also be beneficial to the organism. The effect depends on the nature of the change and where the change occurs. Map out each chromosome with high resolution. Annotation occurs and then the nucleotides of coding and non coding can be determined. Important because they can provide insight into mechanisms genetic diseases and variability. Dna polymorphisms: one of two or more alternate forms (alleles) at a chromosomal region (locus) that differs in a nucleotide base, or have variable number of tandem nucleotide repeats. Many polymorphisms, they are mostly in non coding regions.