Week 6 Flashcards
What is genetic basis to a disease?
Inherited
Acquired
What is an example of genetic changes?
Cancer
What is the consequence of finding genetic basis?
Define the disease
What is risk factor ?
Characteristic or exposure of an individual that increases the likelihood of developing a disease or injury
Genetic molecular changes
What is genetic testing?
Medical test that looks at changes in chromosome, genes or proteins
What are examples of genetic testing?
Confirm a suspected genetic condition
Determines a person’s chance of developing or passing on a genetic disorder
Determines whether a person is a carrier of a certain genetic mutation - inherited by any children they have
Diagnostic - looking at families
Pre-symptomatic
Carrier-status
Prenatal diagnosis
What is not always diagnostic?
Phenotypic observations and tests
What’s mostly hidden?
Genetic risk factors
What do we need to identify ?
Underlying pathology
What is an example of an inherited disease?
Sickle cell disease
What occurs in West Africa?
Prevalence of carrier frequency can be very high
1 in 20 people carrying sickle cell disease gene
What is progeria?
Rare genetic condition that causes a person to age prematurely
What are rare diseases?
Collectively are common
What is Factor V Leiden?
Variant of human factor V Cause an increase in blood clotting Mutation; protein C (anticoagulant protein) is not able to bind normally to factor V - hypercoagulable state Amino acid substitution in that gene 1 in 20 if people are carrying Increases the risk of thrombosis
What is allele frequency?
how common is the genetic variant within the population,
What are genetic markers?
a marker tags a piece of DNA and can be used to track genes in families or populations
STR [short tandem repeat]
a little stretch of DNA sequence CACACA that expands and shrinks and is usually in anonymous region of the genome
Highly variable in length
SNP: single nucleotide polymorphism
single nucleotide one base in the DNA
- Polymorphic – the frequency in the population is > 1%
TERT gene
telomerase reverse transcriptase
Functional consequence synonymous
it means it is in the coding sequence of that gene but does not change the amino acid, its effect is pretty low
Global MAF
minor allele frequency – it is saying 11% of allele in the population are T
TT
least common genotype – it is the minor allele
Testing for disease association
- Determine the allele frequency of a SNP in a group of cases and compare it to the allele frequency in controls
- Are the allele frequencies significantly different?
- If yes - SNP tested is associated with disease - causative/protective
What is LPP associated with?
Coeliac disease
Through consanguineous marriage
the mutation homozygous and causes an autosomal recessive disease
SNP
Most common type of genetic variant among people
