WEEK 13: Genetics And Disease Flashcards
(13 cards)
define polymorphism
One or two (or more) variants of a particular DNA sequence
Define single nucleotide polymorphism
single base pair variation in the DNA of an individual
Define a variant
specific regions of genome that differ between 2 genomes (for individuals)
What can the extent of polymorphism be?
single base pair (SNP) up to whole stretch of DNA (absent or duplicated) - copy number variant
What are the guidelines for categories of variants
benign - pathogenic (and the categories in between, with uncertain significance in between)
2 categories of variants include?
common variants (>0.5% of population)
rare variants (<0.5% of population)
When and where do de novo variants arise?
earliest is in the embryonic development of parents
during aging of parents
post-zygotic (early embryonic development of offspring)
Types of disease causing changes can include?
single gene disorders
chromosomal disorders
What are copy number variants? (CNV)
dosage imbalance of one+ genes
deletions duplocations or other genetic rearrangements occur, causing a loss/gain of genetic material
determining CNV contribution to disease is technically challenging
What are mitochondrial disorders
caused by mitochondrial dysfunction
has unique characteristics
only inherited from mother
What are types of single gene disorders
mutations that affect a single gene, like sickle cell anemia and cystic fibrosis
What are multifactorial disorders
combination of effects of multiple genes like height and osteoporosis
combine the interaction of genes and environment
include coronary artery disease, diabetes, asthma, familial (genetic) + lifestyle/environment
What is a polygenic risk score
genes affect how likely you are to het a disease, hence scores disease for different people in a population, provide a measure of your disease risk due to your genes, helps you recognise how likely you are to get a disease
