Learning Objectives

• Define what is a ‘complex trait’ and a ‘quantitative trait'
• Understand the use of monozygotic and dizygotic twins in genetic studies
• Know that in population genetics, there is both broad and narrow sense heritability
• Define the effect of genetic and environmental factors on phenotype
• Predict quantitative phenotypes based on population data and parental measurements

Traits & Variation

• what is a complex genetic trait?
• what is a complex quantitative trait? examples?
• what is a polygenic vs a multifactorial trait?
• complex genetic traits are caused by the interplay of [3 factors]?
• what is meant by a continuous phenotypic distribution?
• do quantitative traits follow Mendel's laws? explain?
• what is phenotypic variance? formula?
• what are the 3 components of genetic variance?
• what is heritability?
• what is broad-sense vs narrow-sense heritability? formulae?
• what % of the population is under 1-3 SDs?

Twin Studies