MJ slides lecture 2.3

Question 2

Qualitative vs. Quantitative Trait: Define each and give examples

Answer 2

1) Qualitative: You have it or you don’t
-Lung cancer, arthritis, color blindness
2) Quantitative: You have a certain amount of it that is measurable
-Height, hypercholesterolemia, hypertension, obesity

Question 3

Define concordance

Answer 3

Pertains to a pair of relatives regarding both types of traits:
1) They both share a qualitative trait or
2) They share a quantitative trait that is similar in magnitude

Question 4

Define discordance

Answer 4

Pertains to relative pair regarding both types of traits:
1) One of them has a qualitative trait that the other does not or
2) They have values of a quantitative trait that are at opposite ends of the distribution

Question 5

1) _______________ among twins is a powerful tool for studying genetic influence.
2) Define this term

Answer 5

1) Concordance
2) Agreement between traits exhibited by both twins

Question 6

Define twin study

Answer 6

Study of monozygotic (MZ) and dizygotic (DZ) twins.

Question 7

In twin studies, the degree of concordance for a trait is compared in MZ and DZ twins. The greater the difference in concordance between MZ and DZ, the greater the ______________

Answer 7

heritability