L41 BIOL 2970 Lecture Notes - Lecture 31: Overdominance, Epistasis, Intellectual Disability
13 Nov 2017
School
Department
Course
Professor
Document Summary
Phenotype is any measurable trait, either discrete or continuous. Genotype is not phenotype e. g. the marine worm, bonellia. Whether a larvae becomes male or female does not depend on genotype, but rather on whether it develops independently on the sea floor or within the female body which becomes a parasitic male gonad. Male sex is reduced to being a parasitic gonad. In other words, genotype is not necessarily a predictor of phenotype. No discrete phenotypic categories (mild to lethal symptoms) No single factor, either genetic or environmental, is either necessary or sufficient for cad. Complexity of genotype/phenotype relationship represents interactions among multiple genetic and environment factors. No one fa(cid:272)tor a(cid:1005), a(cid:1006), , an is (cid:271)oth ne(cid:272)essary and suffi(cid:272)ient for phenotype b. Many factors are neither necessary nor sufficient for b. Confoundment of frequency and apparent causation in complex systems requires study at the population level. Sickle-cell anemia -- mutation in gene coding hemoglobin b changes the protein structure -- alleles.
