Scientists studying a common disease find that relatives of an individual suffering from the disease are 5-times more likely than non-relatives to also suffer from the disease. However, the disease is not inherited in a simple Mendelian manner. What does this suggest about the genetic basis of the disease, and how would you identify variants that might be associated with it?

Scientists studying a common disease find that relatives of an individual suffering from the disease are 5-times more likely than non-relatives to also suffer from the disease. However, the disease is not inherited in a simple Mendelian manner. What does this suggest about the genetic basis of the disease, and how would you identify variants that might be associated with it?

what question

Complex Genetic Basis of Disease

layout

observation, interpretation

observations

Relatives 5× more likely to have disease
Genetic Nature
Examples
Detection Method
SNP Analysis
Other Methods
Goal

Relatives 5× more likely to have disease

Indicates genetic component, but not Mendelian inheritance

Genetic Nature

Likely polygenic or multifactorial inheritance

Examples

Diabetes, schizophrenia, cancers

Detection Method

GWAS (Genome-Wide Association Studies), family linkage studies

SNP Analysis

Identifies common variants with small effect size

Other Methods

Whole-genome/exome sequencing, polygenic risk scores, gene-environment analysis

Goal

Find associated variants, understand disease risk architecture