Genetics and Environmental Causes of Disease Flashcards
What are the main causes of disease?
+ Genetic
+ Environmental
+ Combination (multi-factorial)
+ Unknown
Through what methods are we able to try and identify the causes of diseases?
+ Laboratory studies
+ Family studies
+ Epidemiology
What is heritability?
The extent that observed differences are due to genes
If traits run in families, what could this be due to?
+ Genetics
+ Social learning (modelling)
+ Operant conditioning (rewards)
+ Chance
Are heritable traits unchangeable?
No.
+ Some are difficult to change
+ Other change across generations (height)
+ Some highly heritable conditions are easily modified:
- vision
- mental retardation due to Phenylketonuria (PKU)
What are ways in which heritability can be measured?
+ Family studies
+ Twin studies
+ Adoption studies
+ Migrant studies
What are the two types of twins?
+ Monozygotic (identical) twins:
- share genes
- share environment
+ Dizygotic (non-identical) twins:
- share same environment
- share same amount of genetic information as any other sibling
What are the potential problems with twin studies?
+ Monozygotic twins share more ‘environment’ than dizygotic twins
+ Monozygotic twins may not have shared the same uterine environment
What sort of things are likely to be influenced by ‘environment’?
+ Infection
+ Injury from chemical agents
+ Injury from physical agents
+ Behaviour
Name some infectious agents
\+ Bacteria \+ Fungi \+ Parasites \+ Prions \+ Protozoa \+ Tropism \+ Viruses \+ Yeast
What are the various modes of transmission of infectious agents?
\+ Droplet \+ Faeco-oral \+ Venereal \+ Blood \+ Water \+ Food \+ Vectors/fomites
+ Horizontal
+ Vertical
+ Zoonoses
+ Nosocomial
What are some of the diseases associated with smoking?
+ Mutagenic: cancer
+ Inflammation: COPD
+ Nicotinic receptors: increases blood pressure and heart rate
+ Endothelial damage
+ Carbon monoxide levels: intrauterine growth retardation
What are the consequences of metabolising alcohol, which underlie disease?
+ Acetaldehyde: carcinogenesis
+ Increases oestrogen levels
+ Decreases NAD levels: alters lipid metabolism
+ Reactive oxygen: damages lipid membranes
+ Decreases vitamin B levels
+ Depresses CNS function
+ Teratogenic (can disturb development of an embryo of foetus)
What can asbestos cause?
Mesothelioma: develops from the cells of the mesothelium, the protective lining that covers most of the internal organs of the body
What is the name of the occupational lung disease caused by inhalation of coal dust?
Coal worker’s pneumoconiosis
