Genetics - Complex Diseases and Pharmacogenetics Flashcards
What are Mendelian traits?
traits controlled by a single gene (monogenic), and follow a Mendelian pattern of inheritance.
What is an example of a mendelian trait?
ABO blood groups, ear lobe attachment
What is the best way to study mendelian traits?
Family studies, using pedigrees and charts.
What are complex traits?
Traits controlled by multiple genes and the environment
What is an example of complex traits?
Height
Weight
Skin colour
What is the best way to study complex traits?
Collect samples of diseases individuals or with a specific phenotype and compressive them with people who don’t express the phenotype.
What are SNPs?
Single Nucleotide Polymorphisms - when a single nucleotide is changed in a DNA sequence.
What are the most common variations from in the human genome?
SNPs
How many base pairs are in the human genome?
3 billion roughly
What is an example of a large genome study?
Human Genome Project
What are GWAS?
Genome Wide Association Studies - we stratify the population into all of the SNPS
How do GWAS occur?
- We collect samples form the population
- We then see their genotypes and look at all of the SNPs
- we do association analysis for all the SNPs across the genome for the trait of interest.
- This allows us to find the risk allele- the alley that is found most commonly in those expressing the trait of interest.
How is a chance of false positiveness introduced in GWAS?
High number of SNPs possible and high number of tests conducted
How do we adjust for GWAS false positiveness?
Multiple testing correction
How do we gain robust finding for GWAS?
Large number of tests