CMMB 403 Lecture Notes - Lecture 3: Genomic Library, Restriction Enzyme, Bacteriophage
Document Summary
Tutorial 3 discovery of hedgehog homologues in mice. Scientists used previously found genes to find homologues in different organisms. Gene was isolated from rest of genome. With sequenced gene, scientists could do expression analysis. Then, they used hedgehog gene to find homologues in vertebrates. Related genes that diverted in function due to a speciation event. Event gives rise to 2 species, both will have a version of the gene. Different species and different genomes that eovlved differently. Related genes that diverted due to duplication within one genome. Ancestral organism has a single gene, duplication occurs, get 2 versions of the same gene. Related genes within the same species, have diverged. Now are different genes with different functions. Related by descent from common dna ancestral origin. At this time it had become clear that genes that played important developmental roles in an organism like drosophila would likely have vertebrate counterparts.