ANT203H5 Lecture Notes - Lecture 7: Robertsonian Translocation, Population Genetics, Homo Sapiens
Document Summary
When dna is copied mistakes can occur. Mutations occur rarely (about 1 error in 10,000,000 bases) These become new alleles in the population. Some times mutations affect large chromosomal regions. More often, they involve nucleotide substitutions, or small insertion/deletions. Let"s review some examples of mutations in these two main categories. Deletion: the elimination of a nucleotide (one or more) Duplication: when the same region is duplicated, and there may be two of the same chromosome rather than one. Insertion: when one chunk of the chromosome ends up on a different chromosome. Paracentric inversion: situations in which the order of the genetic material is inverted. Pericentric inversion: affecting the order of the centromere. Reciprocal translocation: segment of a chromosome, exchange of chromosome from one to the next (happens in two chromosomes) Transition: (more frequent: ct or g a. Synonymous or silent: if there is a change in the third base, it may code for the same amino acid.
