LS7B Week 3 Lab Worksheet You are a genetic counselor and a couple has come to you for advice They have a family history of cancer and are concerned that their unborn third child will also get cancer They provide you with the following pedigrees for two different traits relating to defects in the enzymes separase and topoisomerase Name These two pedigrees represent the same family Genetic testing shows that individual 4 has only nonmutant alleles of both genes and individual 12 has only mutant alleles of both genes Individuals 6 8 9 12 and 14 have cancer The couple just recently learned that their daughter individual 14 has cancer and has both mutations In this lab activity you will use genetic hypothesis testing to determine the probability that the couple s third unborn child will also inherit both mutations and be at risk for developing cancer Part 1 Now that you ve had some practice with using Punnett Squares in the week 2 lab and class let s examine the pedigrees presented above a bit further 1 Let s start by figuring out what kind of trait is caused by the separase mutation Test each of the four possible hypotheses X linked dominant X linked recessive autosomal dominant autosomal recessive and determine which hypothesis cannot be rejected Write your final solution with a brief explanation 2 Having determined which pattern of inheritance cannot be rejected what is the chance that individuals 11 and 12 would have a child affected by the separase defect 3 Now let s figure out what kind of trait is caused by the topoisomerase mutation Test each of the four possible hypotheses and determine which hypothesis cannot be rejected Write your final solution with a brief explanation 4 Having determined which pattern of inheritance cannot be rejected what is the chance that individuals 11 and 12 would have a child affected by the topoisomerase defect 5 Based on your work so far what is the overall probability that individuals 11 and 12 will have a child affected by both separase and topoisomerase defects