12. Association Analysis

Question 1

What is genetic association?

Answer 1

Genetic Association is the presence of a variant allele at a higher frequency in unrelated subjects with a particular disease (cases), compared to those that do not have the disease (controls).

Question 2

What is a loci and a haplotype?

Answer 2

• Locus - A position in the genome

* Haplotype - This is the order of alleles along achromosome

Question 3

What are cases?

Answer 3

Cases are subjects with the disease of interest, e.g. obesity, schizophrenia, hypertension

Question 4

What is required for a case-control study?

Answer 4

• Definition of the disease must be applied in a rigorous and consistent way
• Controls must be as well-matched as possible for non-disease traits
• Such as age, sex, ethnicity, location, etc.
• Controls must be identical to the cases, but should not have the disease