Complex Diseases and Pharmacogenetics Flashcards
What are the two different types of genetic diseases?
mendelian or complex
What is a mendelian disease?
A condition with clear mendelian inheritance patterns, caused by a single gene
What is a complex disease?
A disease controlled by multiple genes, and and the environment e.g CVD
Can a disease explicitly be Mendelian or complex?
It is difficult to say if a disease is one or the other. E.g SCD is caused by point mutation in B-globin chain of haemoglogin. However condition is exacerbated by environmental factors.
What is an SNP?
A single nucleotide polymorphism - DNA sequence variations that occur when a single nucleotide is changed
where do SNPs occur?
in coding or non-coding regions
What is the most common type of variation in a genome?
SNPs
What is meant by heritability?
It is an estimation of the genetic contribution to a disease
what are the causes of phenotypic differences?
- genetic differences
- shared environment
- Unique environment
What are the two ways to measure heritability?
Twin Studies and Genome Wide Association studies
What are Genome Wide Association Studies?
Where you study the genomes of different people and look for an association between specific genetic variations and the different diseases that the people in the study have
What are the downsides of GWAS?
You need a very large sample size
Mass testing is required which needs money and qualified people
When are SNP’s said to be associated with certain conditions?
When SNPs are found to be more frequent in people with a disease compared to people without the disease
What specifically is GWAS lookin for?
Shared SNPs
what is whole genome sequencing (WGS)?
entire genome scrutinised - every SNP can be identified
How do Twin studies work?
Since monozygotic twins share 100% of their genetic material, they can be analysed as any variation will be due to the environment, not genetics
What is pharmacogenetics?
The study of differences in response to drugs due to genetic differences amongst people
what is the aim of Pharmacogenomics?
improve drug therapy and prescribing in the future
What are the 4 possible outcomes of drugs on our body?
- It can be non-toxic and beneficial
- non -Toxic and non -beneficial
- Toxic and beneficial
- Toxic and non-beneficial
genetic variants in drug-related genes are v.rare. What are the consequences of this in clinical trials?
They are unlikely to be spotted in clinical trials (need huge population)
what is Pharmacokinetics?
what the body does to the drug
explain simplistically the process of pharmacokinetics
- drug absorbed
- activated.
- distributed to target site
- has its effects
- metabolised so deactivates
- excreted
What can pharmacogenetics specifically help with?
The development of personalised medicine
where are the majority of drugs absorbed if taken orally? How are they absorbed?
small intestine and use specific transporter proteins;
