Causes Of Disease Flashcards
1
Q
Give a brief overview about the causes of disease
A
- Natural causes of disease were first studied scientifically by Hippocrates, around 400 BCE
- Introduced the concept of etiology
- Diseases can have a single cause or be the product of multiple factors
- Conditions with no known causes are called idiopathic
2
Q
What 2 groups are the “causes of diseases” usually categorised into?
A
- Intrinsic: From within
- Extrinsic: From the outside
3
Q
Describe the intrinsic causes of disease
A
- Changes in the individuals genome e.g. Nuclear or mitochondrial, inherited mutations, de nova mutations
- Typically alter the function of a gene or a group of genes e.g. more or less protein or same amount but more/less activity
- Effects of genetic variations can manifest at a variety of levels
4
Q
At which levels can the effects of genetic variations manifest for the intrinsic causes?
A
- Cell autonomously: Cell X no longer expresses structural protein Y so cell X is the wrong shape
- Cell non-Autonomously: Cell X no longer secretes protein hormone Y so cell X no longer functions
5
Q
List the extrinsic causes for disease
A
- Injury
- Infection
- Nutrition and diet
- Chemical poisoning
- Exposure to Radiation
- Lifestyle e.g. Smoking, Exposure to workplace toxins
6
Q
How can the “causes of diseases” be seen as a grey area?
A
- The terms intrinsic and Extrinsic can be seen as ambiguous
- Causes of diseases are often a chain of events: Are allergies caused by a sensitive immune system (intrinsic) or the preceding allergen (extrinsic)
- Intrinsic or extrinsic depends on the viewpoint
- E.g. Extrinsic to what: The cell, tissue, Organ or body?
7
Q
Describe how there can be multiple causes to a disease
A
- The phrase “One cause leads to one disease” is rarely true
- Many diseases are the products of many interacting factors
- “Risk factors” can be a more accurate term than cause
- Other “diseases” are umbrella terms for a variety of conditions with different causes but similar signs/symptoms/pathologies
8
Q
Describe age as a cause of disease
A
- Age is a contributing factor to many diseases but is it a cause
- Age often just means “time” in the context of causes that accumulate
- E.g Number of mutations increases as time increases which can lead to a cancer risk
9
Q
How can age be seen as an intrinsic cause?
A
- Age can be seen as an intrinsic cause when it describes the biological process of ageing
- For e.g. Ageing -> Menopause -> Decreased Estrogen -> Risk of osteoporosis
- Many diseases associated with chronic inflammation also have biological ageing as a cause
10
Q
What are the alternative descriptions for causes?
A
- For many diseases, causes are grouped as either “genetic” or “environmental”
- These terms are versions of intrinsic or extrinsic that are more reflective of that disease
11
Q
Give an example of these alternative descriptions
A
- E.g. Parkinson’s disease risk factors are
- Aging, Genetics, Environment
- Genetics: Inherited gene variants
- Environment: Exposure to pesticides, herbicides, solvents
12
Q
List some diseases classified as intrinsic
A
- Cancer: Leukaemia, Lymphoma, Myeloma, Breast, Prostate
- Developmental diseases: Neural tube defects
- Inherited anaemia: Sickle cell disease
- Inherited metabolic diseases: Phenylketonuria
13
Q
Idk this slide
A
14
Q
Are the causes of Down Syndrome Intrinsic or Extrinsic?
A
- Intrinsic
- Trisomy of chromosomes 21, Inherited at conception
15
Q
Are the causes of Covid-19 Intrinsic or Extrinsic?
A
- Extrinsic
- Infection with SARS-CoV-2
