Lecture 20: X-linked traits & Recombination

Question 1

In what insect is eye colour a sex linked trait

Answer 1

Drosophila (fruit flies)

Question 2

How many genes in humans

Answer 2

~20,000

Question 3

What are recombinant types

Answer 3

combination of parental genes in a new way not present in either of the parents (think of flies)

Question 4

Linked genes show biases towards which genotypes?

Answer 4

Parental genotypes, and not recombinant.
(Violates Mendel’s 2nd law)

We can still get recombination though, due to random crossing over in meiosis (late prophase 1)

Question 5

How can we determine the order and location of genes within a chromosome?

Answer 5

By using recombination frequencies