On my honor, this is my work GENETICS 310 EXAM I all, 2017 I. Australian daises have 4 chromosomes (2 pairs). A gene on chromosome 1 affects petal color where M M is magenta, M M is pink and MM flowers have white petals. A dominant gene on chromosome 2 causes Cut leaves, while homozygous recessive plants have smooth leaves. A truebreeding white, cut is crossed to a magenta, smooth. A) Give a legend for the inheritance of Cut vs. smooth leaf: C_ cut cc smooth B) Give the genotypes of the two parents: MM, CC X M M, cc C) Show the chromosomes, including the alleles on each, in the 1 hybrid progeny at metaphase of Meiosis 1 and mitosis. D) Write the 1 genotype and predicted 2 phenotypic ratios if 1 plants are self pollinated. 1 genotyype M M, Cc, 2 phenotypic ratio (1M M :2M M : 1 MM) X (3C_ : 1 cc) gives: 3 Magenta, cut: 1 Magenta, smooth: 6 pink, cut: 3 pink, smooth: 3 white, cut :1 white, smooth E. This problem provides examples of (check correct answers: X Simple dominance epistasis X incomplete dominance X Independent assortment epigenetic effects variable expressivity. Suggest two different crosses that could be used to determine if a Cut leaf 2 plant is heterozygous: write the crosses and predicted progeny for either case. 1. Test cross to a cc plant: CC gives all Cut. Cc gives 1 cut : 1 smooth 2. Self pollinate CC gives all Cut, Cc gives 3 cut : 1 smooth
II. In mice: OB_ obese T T lethal B 1 _, B 2 _ black 0b/0b lean T T tailless B 1 _, b 2 b 2, albino TT tail b 1 b 1, B 2 _ albino b 1 b 1, b 2 b 2, albino An obese, tailless albino female is crossed to a lean, tailless male who is also an albino. Some of the many progeny are lean but all of them are black. a) Give potential genotypes for the male and female mice: female OB/ob T T B 1 B 1, b 2 b 2 male ob/ob, T T, b 1 b 1, B 2 B 2 b) What fraction of the progeny would be expected to be obese and tailless? ½ X 2/3 c) What fraction of the progeny would be expected to be OB/ob, TT? ½ X 1/3 d) Predict the coat-color genotype of the black progeny B 1 b 1, B 2 b 2 e) If the black progeny are inter-mated, what fraction of their progeny would be expected to be black? (Assume B 1 and B 2 are independent genes) 9 B1_, B2_ : 3B1_, b2b2 : 3 b1b1, B2_ : 1 b1b1, b2b2 gives 9 black to 7 albino f) If the original cross between a tailless male and female produced 9 progeny, i) what is the probability that 6 will be tailless and 3 will have tails? (show answer as a formula) 9! (2/3) 6 (1/3) 3 6!3! ii) what is the probability at least one of the 9 will be tailless? 1-(1/3) 9
III. The first column in the table below has for a term that describes difficulties encountered in genetic analysis, the second has a definition and the 3 rd has examples that may apply to the term. Place the number of the definition and letter of any examples that apply to the term in the space provided. Term Definition Example 1. phenotype does not A 5,E pleiotropy match genotype Zika virus 6,D phenocopy 4, variable expessivity 8,C age of onset 1,G lack of penetrance 7,B genetic heterogeneity 2,A teratogen 3,H codomimance 2. an agent that causes birth defects during pregnancy 3. Different alleles of one gene may be expressed in different cells 4. range of phenotypes from the same gene defect 5. multiple organs are affected 6. environment causes the same defect as an inherited mutation 7. different single genes cause the same phenotype 8. symptoms develop at variable times after birth B inherited blindness C Huntington disease D fluoridone induced albino plants E galactosemia black spots in peas G polydactyly in some pedigrees H roan cattle IV. The mother in this pedigree has just been diagnosed with EHK, a very rare late onset disease that is dominant. Circle the pedigree(s) below that reflect possible outcomes for this family. V. A man with HLA genotype A3 B4/ A1 B6 marries a woman with A5 B10/ A2 B3. List 4 different probable HLA genotypes that may appear in their children. A3 B4/ A5 B10 A3 B4/ A2 B3 A1 B6/ A5 B10 A1 B6/ A2 B3
VI. In the table below list the bloodgroups (, MN, Rh), if any, that would eliminate each individual mom or dad as parent of the child in question: Child A, M, rh- MN M A AB, N AB B, MN, rh- Now do the same using data for the prospective parents in the table below: Couple child 1 A, M, rhchild 2 A child 3 child 4 B, MN, rh- Rh O, Rh MN MN, MN, MN, MN MN, MN, MN MN MN VII. True or alse Monozygotic twins reared apart are as similar as those reared together. T In some monozygotic twins, one is male and the other female, If heritability for a trait is 1 for a trait, it cannot be altered by environment. Suspicion about Burt s IQ H 2 studies was raised by different results in other tests. Dizygotic twins are more common than monozygotic twins. Dizygotic twins should have the same HLA alleles half the time.
VIII. lies from a purebreeding strain with 6 bristles per mm along the edge of the wing are crossed to another strain that also has 6, as do the 1 hybrid flies. However in the 2 generation a small % of the flies have none while a similar fraction have 12. While 2 flies with each number of bristles/mm from 0 to 12 are found, the average is still 6. A. How many QTL genes are involved in bristle number in these flies 6 and how do you know? 2N + 1 classes = 13: N = 6 B. Using your answer for A, what fraction of the 2 will have 0 bristles? (¼) 6 C. Does transgressive segregation occur in this example? yes How do you know? 2 s from 0 to 12 greatly exceed the 6 bristles of the parents D. Show potential genotypes for the two original purebreeding parents and the 1 hybrid: P1 A A B B C C DD EE P2 AA BB CC D D E E 1A A B B C C D D E E E. How many bristles does each contributing allele contribute?. Variance (V) in the truebreeding parents was 1 in both cases and 4 in the 2. Show the values for V T, V A, V G and H 2 in this case, V T, 4 V E, 1 V G 3 H 2 3/4