Mapping three genes in a single cross: generic a, b, c mutant loci (a+, b+, c+ = wild type).               a, b, c               x          a, b, c             a+, b+, c+                      a, b, c                           Offspring:        a, b, c = 870                                                 a+, b+, c+ = 855                                                 a+, b, c = 65                                                 a, b+, c+ = 63                                                 a+, b+, c = 67                                                 a, b, c+ = 65                                                 a+, b, c+ = 8                                                 a, b+, c = 7 Determine the map distance between each gene and draw a map showing the map distance and the order of the three genes.

Draw all possible linkage maps for these three genes.

CIUSS O An organism has the genotype a g*/a"g*; qf"/q+f*;r+h+/rth*. Indicate the correct genes/ alleles at all the positions numbered 1-12 in the image below such that the diagram accurately represents the genotype of this organism. Note: assume the first chromosome in each pair shown in the genotype is the top chromosome shown in the diagram. 1 i 2: a gene g gene 6. q gene fgene 7 8. | 10 r gene h gene 12 Only place the genes/ alleles you need. You will not need them all. You may need to use some more than once. • gene / allele 1 a- ; gene / allele 2 g+ ; gene / allele 3 a- gene/allele 4 g++ • gene / allele 5 q- ; gene / allele 6 f- gene / allele 7 q+; gene / allele 8 f- gene / allele 9 r+; gene / allele 10 h+ gene / allele 11 r+ gene / allele 12 h+ a+ a- f+ f- g+ g- h+ h- q+ q- r+ r- 2.

From a cross between e+ f+ g+ and e− f − g− strains ofNeurospora, recombination between these linkedgenes resulted in a few octads containing the followingordered set of spores:e+ f+ g+e+ f+ g+e+ f − g+e+ f − g+e− f − g−e− f − g−e− f − g−e− f − g−a. Where was recombination initiated?b. Did crossing-over occur between genes e and g?Explain.c. Why do you end up with 2 f+ : 6 f − but 4 e+: 4 e−and 4g+: 4g−?d. Could you characterize these unusual octads as MIor MII for any of the three genes involved?Explain.

You have a garden and some pea plants have dark leaves and others have striped leaves. You conduct a series of crosses (1 through 5) and obtain the results given in the table. What is the genotype of the parents in cross 1? A) Aa x aaB) Aa x AaC) aa x aaD) AA x aa

Consider the following Test Cross results & chromosome map: Test Cross Progeny 525 A   B  C 500 A+ B+C+ 456 A+ B C 308 A  B+C+ 101 A  B  C+ 100 A+ B+C 2 A+ B C+ 1 A  B+C Total Progeny = 1993   1-Based on the above data calculate the expectednumber of Double crossovers (DCOs)? Round answers to the closest whole number.

Label the diagram: 3 5' Primer 5' 5' ¹3'

calculate the frequency of recombination among male parents and female parents separately.

Consider the following cross involving three linked genes DeF/dEf x def/def. PHENOTYPES NUMBER OBSERVED DeF 76 def 30 dEf 82 DEF 24 Def 4 DEf 18 dEF 1 deF 15 The gene order is:

Suppose researchers studied the first chromosome of a new species and mapped three genes of interest, indicated as a, b, and c. A three‑factor cross was performed and the number of gametes formed from the F2 generation was recorded in a table. Note that the order of genes in the table is arbitrary. Calculate the recombination frequencies for each given gene pair in map units. a+ b+ c+ a b c a b+ c+ a+ b c a b+ c a+ b c+ a b c+ a+ b+ c 173 176 35 33 11 10 3 1 After completing the gene mapping, the researchers treated individuals to induce inversions in the chromosomes. After treatment, another three‑factor cross was performed and the number of gametes formed from the F2 generation was recorded in a second table. Note that the order of genes in the table is arbitrary. a+ b+ c+ abc a b+ c+ ?+ b c a b+ c a+ b c+ a b c+ a+ b+ c 188 185 24 26 1 0 49 46 Calculate the recombination frequencies for each given gene pair in map units.