Lecture 3 April 10, 2012 “Extensions on Mendel” *Two Questions to ask- is it dominant or recessive, autosomal or sex linked• Alleles can interact with each other in complex ways - incomplete dominance - codominance • Pleiotropic affect • Many traits are controlled by more than one gene - epistasis - redundancy - complementation - suppression • Penetrance and Expressivity • Interactions of genotypes with the environment Incomplete dominance: The phenotype of the heterozygote is an intermediate between homozygous parents. Segregation of both genotype and phenotype is 1:2:1 - Alleles contribute different amounts of functional protein; total amount determines phenotype. Pigment forming enzyme is present in limiting quantities, so having more makes the flowers more red. Co- dominant – Both parent phenotype
View Full Document
Unlocking...