Human Molecular Genetics - Lecture Twenty Four : The Human Genome and Disease
5 important questions on Human Molecular Genetics - Lecture Twenty Four : The Human Genome and Disease
What is the definition of a mutation and which types of mutations are inherited ?
- A permanent alteration in the DNA sequence
- Can be acquired (through environment) or inherited (from parents gametes)
1. Germline Mutations
- Occur in germline cells (gametes; ova and sperm)
- These can be inherited by the next generation
2. Somatic Mutations
- Occur in somatic cells (diploid cells that don’t form gametes) -
- These can’t be inherited by next generation
What are the roles of mutations ?
- Introduce variation
- If favorable: advantageous
- Drive evolution of a population
- Mutations can bring on damaging/harmful phenotypes that result in a disease state
- Mutation in a part of the DNA that has no function (known)
- Environment→ certain environmental exposures can affect gene expression
- Other genes→ may affect how mutated gene is expressed
Classifying mutation into Dominant vs Recessive
- This means that if we have a mutation in one chromosome, we have a backup: Heterozygous
- Or both copies can be affected: Homozygous
- Only one copy of allele required for it to be expressed
- Two copies of alleles required for them to be expressed
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
Classifying mutations into "Loss of function" vs "Gain of function"
Loss of function :
- Cause production of a protein that doesn’t work well, or not at all
- Recessive
- Gene works better than normal or do something unexpected
- Dominant
Describe genetic determinism in genetics and gene environment interactions
- Having a disease related mutated allele doesn’t mean you will definitely get the disease
- Due to the effect the environment can have on gene expression
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
![Trustpilot Logo](/images/design_2020/lp/clp-trustpilot-en.png)