genome wide approaches to complex diseases

Question 1

large scale genotyping is used for

Answer 1

• molecular diagnosis of diseases
• to search for susceptible genes for complex disorders GWAS
• search for genes related to phenotypic traits
• history of human pop
• detecting SNP underlying domestication traits in plants/animals

Question 2

GWAS require

Answer 2

a high number of SNP and a high number of individuals

Question 3

the phenotype of a complex disease depends of

Answer 3

the balance between the good and the bad predisposing variants, if you are beyond the threshold the you have a higher probability to get sick

Question 4

the manhatten plot

Answer 4

• each dot represents a SNP
• each chromosome has a different color
• the lack of SNP in some chromosomes correspond to the centromere area
• the horizontal line corresponds to the genome wide significance level

Question 5

why is GWAS deposited to public repositories

Answer 5

due to individual efforts and the high cost

Question 6

what can you find in dbGAP

Answer 6

• clinical protocols
• phenotypic data
• association data

Question 7

GWAS disadvantage

Answer 7

• many susceptible variants locate within genic deserts
• the conferred risk of each single variant is very low
• missing heritability

Question 8

odds ratio

Answer 8

is a measure of association between an exposure and an outcome

• OR=1 does not effect odds of outcome
• OR>1 exposure is associated with higher levels of outcome
• OR<1 exposure associated with lower levels of outcome

Question 9

meta analysis

Answer 9

is a statistical method allowing the simultaneous analysis of data coming from different studies