Understanding Heritability in Quantitative Genetics for Breeding Plants and Animals, Study notes of Genetics

Download Understanding Heritability in Quantitative Genetics for Breeding Plants and Animals and more Study notes Genetics in PDF only on Docsity! Genetics 466, Lecture 41 Quantitative Genetics III: Genetics of Plant and Animal Breeding Objective: Learn the concept of narrow-sense heritability as a way of separating the genetic variance into the additive and dominance components. Know how to use quantitative genetics models to estimate "narrow-sense" heritability. Understand the utility of the concept of narrow- sense heritability in plant and animal breeding. Key Terms: Narrow-sense heritability Additive effect (a) Dominance effect (d) Additive variance Selection differential (S) Selection response (R) Additional Problems: 1. If the environment became more uniform what would happen to the heritability? (a) H2 and h2 would both decrease; (b) H2 and h2 would both increase; (c) H2 would increase but h2 would decrease; (d) H2 would decrease but h2 would increase; (e) Both heritabilities would remain the same. 2. An ecologist working with the big blue stem prairie grass would like to know how much additive genetic variation her population contains for the number of days from germination to flowering. The phenotypic variance is 36 days2. She determines that the correlation between parents and offspring is 0.25. What is Va for this population? Answers: (1) Answer = (b) Since V(e) decreases, both V(g) and V(a) would make up a larger part of the total. (2) 18 days2