Biology 1001A Lecture Notes - Lecture 13: Mutation Rate, Outcrossing, Overdominance

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

Document Summary

At a locus one allele may be dominant over another allele. The dominance status of an allele describes its effect on the phenotype of the heterozyotes not whether the allele is helpful, harmful or neutral. Clicker question: most genetic disorders are associated with recessive alleles. In general, recessive alleles tend to be rare. By definition, recessive alleles reduce an individuals alleles. C: selection eventually weeds out all copies of a harmful dominant allele from the population, but a harmful recessive allele can hide from selection in heterozygous genotypes. In other words, the dominant status of a particular allele turns out to be important. It turns out to be a potential constraint on the degree to which selection can favor the spread of a dominant allele. How effectively selection can weed out a deleterious allele. The dominant status of an allele can affect the speed of evolution as well as the possible outcome of evolution.