QUIZ 1 Flashcards
4 things that can predispose or cause a disease
- presence of a gene
- traits that turn genes on/off
- gene - gene interactions
- gene - environment interactions
DNA consists of…
A, C, G, T
DNA in humans is..
double stranded
Mutations on chromosome 14 change to
C-G or A-T
Some minor alleles can..
increase disease risk - Ex: breast cancer
Genetic variation only shows if it’s
Expressed
(transcribed to RNA/Protein)
Changes that determine gene expression
Epigenetics
Nucleosomes
Repeating units of chromatin - made of 146 base pairs of DNA wrapped around Histone
Histone
Positively charged proteins - structural scaffolds for DNA packaging: H2A, H2B, H3, H4
Histone Acetyltransferase (HAT)
enzymes that add acetyl groups to histone proteins, loosen chromatin - allow gene expression
- reversible modification, balanced by HDAC > uncoiling and transcription
Histone Deacetylase (HDAC)
enzymes that remove acetyl group from histone > condensed/ closed structure of chromatin and less transcription
Euchromatin
less dense transcriptionally active DNA - open arms
Heterochromatin
Densely packaged transcriptionally inactive DNA - hibernating > gene repression
Methylation
Addition of methyl groups to DNA or Histone tails - often altering chromatin structure + reducing gene expression > occurs in cytosine rich sequences called CpG sites
Gene silencing
HDAC and Methylation combine. Permanent method of down - regulating transcription of genes
- turn off gene so it can’t produce product - often through chromatin or RNA interference
Genetic changes interact..
with each other
Chronic Conditions - common complex diseases..
symptoms arise due to variety of factors - ex: Asthma
Gene - Gene interaction
Epistasis
- effect of one gene influenced, modified, masked by other genes
Gene - Environment interaction
genetic backgrounds differ in different environments - ex: air pollution can affect asthma
Race is a social construct.. NOT
biological
CRISPR
technology able to cut specific genes
How does genomics have increasing role in public health?
disease prevention and health promotion
why is a “tiered” system for genomic test and individual health important?
make sure it’s used when most important and necessary
how genomics is creating change and improvement
familial hypercholesterolemia - “fix”it - prevent from passing down
what would you study about genomics and why?
diabetes - underlying factor for many other things, something that feels like you could fix
Tier 1 Evidence for Recommendation
Supported by a base of synthesized evidence for implementation in practice
Tier 1 Examples
HBOC, Lynch syndrome, FH, Newborn screening
Tier 2 Recommendation
Synthesized evidence is insufficient to support routine implementation in practice, may provide information for decision making
Tier 2 Examples
Many pharmacogenomic tests
Tier 3 Recommendation
Evidence based recommendation against use; or irrelevant synthesized evidence identified; not ready for routine implementation in practice
Tier 3 Examples
Direct - to - Consumer personal genetic tests
