The table (Table 25.2) lists concordance values for MZ and DZ twins with respect to a number of discrete complex traits. a. How do you know at a glance that the heritabilities of all these traits are less than 1.0? b. To estimate the heritabilities of these traits, which equation will you use and why? c. Calculate the heritability for each trait. For which trait is the contribution of genetic variance compared to total phenotypic variance more than any other in the table? Trait MZ Concordance DZ Concordance Type 1 diabetes 0.43 0.074 Type 2 diabetes 0.34 0.16 Schizophrenia 0.41 0.053 Autism spectrum 0.94 0.047 Alzheimers disease 0.32 0.087 Parkinsons disease 0.16 0.11 Multiple sclerosis 0.25 0.054 Crohns disease 0.38 0.02 Colorectal cancer 0.11 0.05 Breast cancer 0.13 0.09 Prostate cancer 0.18 0.03

#9 The table (Table 25.2) lists concordance values for MZ and DZ twins with respect to a number of discrete complex traits. a. How do you know at a glance that the heritabilities of all these traits are less than 1.0? b. To estimate the heritabilities of these traits, which equation will you use and why? Calculate the heritability for each trait. For which trait is the contribution of genetic variance compared to total phenotypic variance more than any other in the table? C. Trait Type 1 diabetes Type 2 diabetes Schizophrenia Autism spectrum Alzheimer's disease Parkinson's disease Multiple sclerosis Crohn's disease Colorectal cancer Breast cancer Prostate cancer MZ Concordance 0.43 0.34 0.41 0.94 0.32 0.16 0.25 0.38 0.11 0.13 0.18 DZ Concordance 0.074 0.16 0.053 0.047 0.087 0.11 0.054 0.02 0.05 0.09 0.03 #9 The table (Table 25.2) lists concordance values for MZ and DZ twins with respect to a number of discrete complex traits. a. How do you know at a glance that the heritabilities of all these traits are less than 1.0? b. To estimate the heritabilities of these traits, which equation will you use and why? Calculate the heritability for each trait. For which trait is the contribution of genetic variance compared to total phenotypic variance more than any other in the table? C. Trait Type 1 diabetes Type 2 diabetes Schizophrenia Autism spectrum Alzheimer's disease Parkinson's disease Multiple sclerosis Crohn's disease Colorectal cancer Breast cancer Prostate cancer MZ Concordance 0.43 0.34 0.41 0.94 0.32 0.16 0.25 0.38 0.11 0.13 0.18 DZ Concordance 0.074 0.16 0.053 0.047 0.087 0.11 0.054 0.02 0.05 0.09 0.03