15. Mutations Flashcards
What are possible causes of mutation?
ionising radiation
Chemical mutagens
Replication errors
Virus infection - HPV
What is a germ line mutation?
Mutations in the gametes (eggs or sperm) which will be passed onto offspring and affect all cells in the body.
What is a somatic mutation?
Mutation which occurs in a body cell. This will not be passed on to offspring.
Why are RNA polymerase more prone to making mistakes then DNA polymerase?
RNA polymerase does not proof read like DNA polymerase
Why are the long term effects of errors in transcription and translation less severe than a genome mutation?
- RNA is quickly degraded, so errored copy will be quickly removed
- it isn’t inherited, so change will not be passed on
- the cell will make multiple copies of RNA, so unlikely to keep making the same mistake
How is mitochondrial DNA inherited?
Maternally
What type of mutations can mitochondrial DNA suffer from?
Germ line and somatic
What is the result of a mitochondrial germ line mutation?
Mitochondrial disease
Which organs are most likely to be affected by a mitochondrial germ line mutation?
high energy organs - heart, brain and muscles
Give an example of an autosomal recessive disease.
Cystic fibrosis
Anaphase lag in mitosis will cause….
Wrong number of chromosomes - one cell will have 2 copies and the other 0 copies.
If a parent is unaffected and a child is affected by an autosomal dominant disease, what can you conclude?
Must be a spontaneous mutation in the child
Where do primordial germ cells migrate to and from?
Orginate in gut mesentery and migrate to gonads
Loss of function mutations are typically what type of inheritance?
Recessive
What do loss of function mutations typically affect?
Biochemical pathways
