quantitative genetics

Question 1

what is phenotype influenced by

Answer 1

genetic and environment (non genetic)
P = g + e

Question 2

phenotype variation equation

Answer 2

Vp = Vg + Ve

Question 3

heritability calculation

Answer 3

H2 = genetic variation/phenotype variation

Question 4

narrow sense heritability calculation

Answer 4

h2 = VA/(Va + VE)

Question 5

define heritability

Answer 5

the genetic variation as proportion of the phenotypic variation

Question 6

causes of low heritability estimates

Answer 6

errors in pedigree recording
misclassification of phenotype
large phenotypic variance
low additive genetic variance

Question 7

correlation

Answer 7

association between 2 quantities and how one changes when the other changes

Question 8

phenotypic correlation

Answer 8

one characteristic observed with another characteristic

Question 9

genetic correlation

Answer 9

genetic merit for one trait associated with genetic merit for another trait

Question 10

causes of genetic correlation

Answer 10

• one gene affects two traits (pleiotropy)
• genes are close together so in linkage ( linkage disequilibrium)

Question 11

estimated breeding values

Answer 11

= the best estimate of genetic merit of an individual
calculate by removing systematic environmental effects on measured phenotypes

Question 12

what is estimated breeding values calculated from

Answer 12

pedigree
own performance
relatives performance

Question 13

predicted transmitting ability

Answer 13

the expected deviation of progeny’s performance from population mean
= 1/2 EBV