Biology 1001A Lecture Notes - Lecture 13: Coefficient Of Relationship, Balancing Selection, Disruptive Selection

• School: Western University
• Department: Biology
• Course: Biology 1001A
• Professor: Tom Haffie

Document Summary

Clicker q: most genetic disorders are associated with recessive alleles. Dominance status of an allele describes its effect on the phenotype of heterozygotes not whether the allele is helpful, harmful or neutral. If a harmful allele is dominant, it eventually is weeded out through selection. If a harmful allele is recessive, selection is not able to weed out every recessive allele, and it stays within the population. If a beneficial allele is dominant it increases in frequency very quickly. If a beneficial allele is recessive it increases in frequency, but much slower. Why is genetic variation important: total amount of genetic variation affects the evolutionary potential. Inbreeding decreases fitness in individuals because they are not genetically diverse. Quantifying genetic variation: of an individual: proportion of heterozygous loci (higher is more diverse), and the inbreeding coefficient, of a population: proportion of polymorphic loci (the fraction of individuals in a population that are heterozygous)