Chapter 5: Genetic linkage and mapping in eukaryotes

Question 1

What is a linkage group? What are the two linkage groups?

Answer 1

All genes located on the same chromosome
Syntenic - on same chromo
linked genes - very close together

Question 2

Describe the coupling configuration?

Answer 2

AB / ab (cis)

Question 3

Describe the repulsion configuration?

Answer 3

Ab/aB (trans)

Question 4

Describe the four possible gametes if crossing over of M and W occur?

Answer 4

creates parental and nonparental gametes

Question 5

How do you tell if genes are linked via independent assortment?

Answer 5

dihybrid Test cross….
F1 produce double heterozygote and cross with double homozygous recessive
gamete formation - AB = 25%, ab = 25%, aB = 25%, Ab = 25% (separate chromosomes)
1:1:1:1

Question 6

How to tell if genes are linked via genetic linkage?

Answer 6

F1 produce double heterozygote, cross with double homozygous recessive
gamete formation =
D/e= greater than 25%
d/E = greater than 25%
D/E = less than 25%
d/e = less than 25%
(SAME chromo)

Question 7

How can you tell is two genes are linked?

Answer 7

testcross

Question 8

Process to tell if two genes are linked?

Answer 8

1) dihybrid testcross
2) if independent assortment
——1:1:1:1
3) if syntenic
——- Parental classes (more common) > Recessive classes
4) Chi square (checks results)