Name KEY 7 03 Final Exam 2005 KEY Name KEY The exam starts at 9 am and ends at 12 pm There are 18 pages including this cover page Please write your name on each page Only writing on the front of every page will be graded Question 1 24 pts Question 2 26 pts Question 3 20 pts Question 4 24 pts Question 5 24 pts Question 6 22 pts Question 7 34 pts Question 8 26 pts TOTAL out of 200 1 Name KEY 1 24 pts You are studying three autosomal mutations in flies Each of these three mutations lies in a different gene All three genes lie on the same autosome The wn1 mutation is recessive and causes the phenotype of short wings wild type flies have long wings The wn2 mutation is recessive and also causes the phenotype of short wings The ey mutation is dominant and causes the phenotype of small eyes wildtype flies have big eyes You cross true breeding wn1 wn2 short winged females to true breeding ey males to obtain an F1 generation You then cross female F1 flies to true breeding wn1 wn2 big eyed males You analyze the resulting progeny and find that there are flies in the progeny from all four phenotypic classes Short wings Small eyes Long wings Small eyes Short wings Large eyes Long wings Large eyes For parts a c write out complete genotype s and phenotype s of the flies we ask for By complete genotype we mean the genotype at all loci discussed in the problem By complete phenotype we mean the phenotype at all traits discussed in the problem If there are multiple answers write ALL POSSIBLE answers Use to indicate wild type alleles a 6pts Write out complete genotype s and phenotype s of both parents Phenotype Genotype wn1 wn2 ey Short wings big eyes P generation mother wn1 wn2 ey P generation father Long wings small eyes wn1 wn2 ey wn1 wn2 ey b 6pts Write out complete genotype s and phenotype s of F1 flies Phenotype Genotype F1 generation wn1 wn2 ey Long wings small eyes mother of F2 wn1 wn2 ey Father to whom you cross the F1 mother Short wings big eyes wn1 wn2 ey wn1 wn2 ey 2 Name KEY c 8pts Write out complete genotype s of the different F2 flies Phenotype Short wings Small eyes Genotype wn1 wn2 ey OR wn1 wn2 ey OR wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey Long wings Small eyes wn1 wn2 ey wn1 wn2 ey Short wings Large eyes wn1 wn2 ey OR wn1 wn2 ey OR wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey Long wings Large eyes wn1 wn2 ey wn1 wn2 ey d 4pts Remember from class that oddly enough male flies do not undergo recombination during meiosis You cross true breeding wn1 wn2 short winged females to true breeding ey males to obtain an F1 generation You then cross male F1 flies to true breeding wn1 wn2 big eyed females If you analyze 2000 resulting progeny predict the number of the following kinds of flies that you will get Phenotype Short wings Long wings Short wings Long wings Small eyes Small eyes Large eyes Large eyes Number of flies 0 1000 1000 0 You cross an F1 male wn1 wn2 ey to a female wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey There are no recombinants so the male either gives the top chromosome or the bottom chromosome and the female always gives wn1 wn2 ey Thus all F2 flies are either wn1 wn2 ey OR wn1 wn2 ey wn1 wn2 ey wn1 wn2 ey 3 Name KEY 2 26 pts You are studying a new species of primate that is diploid and has four pairs of autosomes You have found a rare autosomal recessive disease that is lethal in old age and is prevalent in a primate family living in the wild The mother Individual 2 has already died from this disease You want to find the genetic locus responsible for this disease and decide to use SSR mapping to do so Your first step is to determine which chromosome the locus responsible for the disease is located on You have access to blood samples of all living members of the family and you use these blood samples to genotype each living member of the family at four SSRs SSR12 on chromosome 1 SSR13 on chromosome 2 SSR14 on chromosome 3 SSR17 on chromosome 4 The pedigree of the primate family and the SSRs possessed by each family member are shown in the chart below Assume complete penetrance and no new mutations Individual 1 Individual 2 SSR 12 AB AA AA AB BB AB AA BB AA BB AB AB AB 13 BC AC BB BB AC AC BB AC BC BB AA AB BB 14 AC AB BC BC AB AB AB BC BC AB BC B AB 17 AB AB AB AB AB BB BB AB BB BB AB B BC 4 Name KEY a 4pts Fill in the empty column of the chart which indicates the deceased mother s genotypes at each of the four SSRs Indicate any ambiguous alleles with a questionmark b 4pts If you want to determine the LOD score for this family for the locus responsible for the disease and one SSR which parent s would be relevant Individual One Individual Two or both Individual One because he is heterozygous at all loci involved c 4pts Do you know the phase of the parent s you listed in part b No because you do not know his parents For parts d and e calculate the LOD score at 0 1 for this family for the locus responsible for the disease and each of the following SSRs For each LOD score clearly write the expression you used to calculate the LOD score d 7pts the locus responsible for the disease and SSR12 1 2 0 45 3 0 05 4 1 2 0 05 3 0 45 4 1 33 7 0 25 Since you do not know the genotypes of the parents of Individual One there are two possible phases for Individual One We will call the allele that does not confer the diease and the allele that does confer the disease Phase One Phase Two B from father parental B from father recombinant A from father parental A from father recombinant A from father recombinant A from father parental B from father recombinant B from father parental log The first child received A The second child received A The third child received and The fourth child received B The fifth child received and The sixth child received A The seventh child received B The eighth child received A The ninth child received B 5 Name KEY You cannot tell whether children three and five are recombinants or parentals because you cannot tell which allele was given to these children by Individual One Thus these meioses are not informative and cannot be included in the analysis For phase one there are three parental children and four …
View Full Document
Unlocking...