220 likes | 346 Views
G e n e t i c s N e w s. Summary for Exam II - Do it NOW!. Office hours underutilization. Problem Set 7 available. Problem Set 8 available. Exam I …. not available. Our answers and comments on web. Click on Course at a Glance; then Click on Exams; Answer Keys. Topics for Today.
E N D
GeneticsNews • Summary for Exam II- Do it NOW! • Office hours underutilization • Problem Set 7 available • Problem Set 8 available • Exam I … not available Our answers and comments on web. Click on Course at a Glance; then Click on Exams; Answer Keys
Topics for Today • Sex linkage/Sex limitation • Calculation of probabilities from pedigree • Extension of Mendelian Genetics - Multiple alleles determining one trait - Multiple genes determining one trait - Multiple genes with additive effect
Study Question 6 How is the trait inherited? x Dd Dd Autosomal dominant Dd
Study Question 6 How is the trait inherited? Dd Dd Autosomal dominant x Autosomal recessive dd Dd Dd Dd Dd dd dd
Study Question 6 How is the trait inherited? XDY XXD Autosomal dominant Autosomal recessive XDY x Sex-linked dominant
Study Question 6 How is the trait inherited? XXd Autosomal dominant Autosomal recessive XXd XY XXd XdY XY Sex-linked dominant XdY XdY Sex-linked recessive
Study Question 6 Could it be an autosomal dominant trait limited to males? Dd Dd Yes dd Dd Dd Dd dd Dd Dd
Study Question 8 What is the probability that IV.1 will get the disease? Specify: P(III.2 x III.3 XdY) XXd Parse: Solve: XXd? XY P(III.2 is XXd) AND P(III.2 passes Xd) ? 1/2 1/2 XdY ? AND P(III.3 is XY) AND P(III.3 passes Y) 1 Probability = 1/8 1/2
Multiple Genes/One Trait Conventional dihybrid cross Substrate1 Product1 Substrate2 Product2A B
Multiple Genes/One Trait Dihybrid cross of interacting genes 9 : 3 : 3 : 1 =9 : 7 Substrate1 Substrate2 ProductA B
Multiple Genes/One Trait Dihybrid cross of interacting genes 9 : 3 : 3 : 1 =9 : 7 chorismate compound X tryptophanM N
Study Question 17 You cross a vermilion-eyed fly with a cinnibar-eyed fly to obtain F1 progeny, then you cross these progeny to get F2 progeny. What phenotypic ratio do you expect?
Study Question 17 Dihybrid cross of interacting genes Substrate1Substrate2ProductV C
Study Question 17 Dihybrid cross of interacting genes 9 : ? : ? : ? Substrate1Substrate2ProductV C
Study Question 17 Dihybrid cross of interacting genes 9 : 3 : ? : 1 Substrate1Substrate2ProductV C
Multiple Genes/One Trait Dihybrid cross of interacting genes 9 : 3 : 3 : 1 =9 : 3 : 4 9 : 3 : 3 : 1 Substrate1Substrate2ProductV C
Study Question 19 Conventional dihybrid cross Pathway where dihybrid cross gives 15:1 ratio? Substrate1 Product1 Substrate2 Product2A B
Study Question 19 What kind of genetic situation can you imagine that would lead to a 15:1 phenotypic ratio? 9 : 3 : 3 : 1 9 : 3 : 3 : 1 15 : 1 Substrate1 Product1 Substrate2 Product2A B
Study Question 20 You find corn with kernels in the ratio: Yellow 247 Golden 154 Sickly green 23 Hypothesis? Hypothesis: One gene, multiple alleles AB x CD 1:(1:1):1= 1:2:1
Study Question 20One gene hypothesis Exp Obs You find corn with kernels in the ratio: Yellow 247 Golden 154Sickly green 23 TOTAL 424 212106106424 Unit = 424/4 = 106
Study Question 20Two gene hypothesis You find corn with kernels in the ratio: Yellow 247 Golden 154 Sickly green 23 Hypothesis? Hypothesis: Two genes for one trait AaBb x AaBb 9:3:3:1
Study Question 20Two gene hypothesis Exp Obs You find corn with kernels in the ratio: Yellow 247 Golden 154Sickly green 23 TOTAL 424 238.5 = 26.5 x 9159 = 26.5 x 6 26.5 = 26.5 x 1424 Unit = 424/16 = 26.5