2. P. 280

3. Linkage Mapping Problem 1: Mating: AaBb x aabb A = Long antennae a = Short antennae B = Green eyebrows, and b = Blue eyebrows. How do you tell your genes are linked? Prediction for 2000 offspring?

4. Problem 1 Results Long Green - 850 Long Blue - 150 Short Green - 150 Short Blue - 850 (Total # crossovers/total # offspring) x 100 = LMU (or cM).

5. Problem 2 – Autosomal Mapping Drosophila: Wing shape – wild/arc Body color – wild/black Progeny: 660 wild 530 black 490 arc 712 arc black

6. Problem 3: Sex-linked cross Sex linked: eye color – wild type/white Body color – wild type/yellow Male Progeny: Yellow white – 43 White – 2146 Yellow – 2302 Wild - 22

7. Problems for additional practice: Example: p. 280 p. 291, #4 p. 291, #5 Online textbook quiz questions for Ch. 15

8. Problem 4: Three point test cross Corn: Growth habit – normal/lazy Leaf appearance – normal/glossy Endosperm – normal/sugary Progeny: 286 wild 272 lazy glossy sugary 40 glossy sugary 33 lazy 44 lazy sugary 59 glossy 2 lazy glossy 4 sugary

9. Problem 5 - Imaginary Critters D = Calm personality d = Dithery personality F = Five toed f = Four toed G = Smooth fur, and g = Grizzled fur. Progeny: Calm, Five, Smooth – 616 Dithery, Five, Smooth - 5 Calm, Five, Grizzled – 104 Dithery, Five, Grizzled - 75 Calm, Four, Smooth – 78 Dithery, Four, Smooth - 100 Calm, Four, Grizzled – 2 Dithery, Four, Grizzled - 620

10. Problem 6 - Groodies Groodies are useful (but fictional) haploid organisms that are pure genetic tools. A wild-type groody has a fat body, a long tail, and flagella. Mutant lines are known that have thin bodies, or are tailless, or do not have flagella. Groodies can mate with each other (although they are so shy that we do not know how) and produce recombinants. A wild-type groody mates with a thin- bodied groody lacking both tail and flagella. The 1000 baby groodies produced are classified as shown in the following illustration. Assign genotypes, and map the three genes. (Problem 18 from Burton S. Guttman.)

11. Assign genotypes, and map the three genes.

12. Problems for additional practice: p. 292, #10 & 11 Online textbook quiz questions for Ch. 15

13. Constructing a Linkage Map

15. Problem 7 – Chromosomal Linkage Mapping Four genes on chromosome: ABCD Linkage data: A & B = 7 LMU A & C = 6 LMU A & D = 4 LMU B & C = 1 LMU B & D = 11 LMU C & D = 10 LMU

16. Problem 8 – Chromosomal Linkage Mapping Four genes on chromosome: ABCD Linkage data: A & B = 17 LMU A & C = 7 LMU A & D = 13 LMU B & C = 10 LMU B & D = 4 LMU C & D = 6 LMU

17. Problem 9 – Chromosomal Linkage Mapping Five genes on chromosome: ABCDE Linkage data: A & B = 3 LMU A & C = 11 LMU A & D = 9 LMU A & E = 9 LMU B & C = 8 LMU B & D = 6 LMU B & E = 12 LMU C & D = 2 LMU C & E = 20 LMU D & E = 18 LMU

18. Problems for additional practice: p. 292, #8 Online textbook quiz questions for Ch. 15 http://www.tinyurl.com/linkagemap