What causes mutations? < mistakes when the DNA is copied < environmental factors such as UV light, radiation < chemicals / drugs, cigarette smoke ...... mutagens
Not all mutations cause problems
Often cells recognize a developing mutation and repairs it before it becomes a fixed mutation
How do we inherit mutations? Each of our genes is a copy from either our mom or our dad. If there is a mutation in one of these genes, this can be passed on from parent to child.
Examples: Sickle cell anemia is caused by a mutation in the gene that instructs the building of a hemoglobin. Red blood cells become abnormal, rigid, sickle shape, making it difficult for the cells to flow through small blood vessels. However, in African populations, having this mutation also protects against malaria.
Mutations can disrupt normal gene activity and cause diseases, like cancer? Cancer is caused by mutations occurring in a number of growth-controlling genes.
(Codon: a sequence of three nucleotide which together form a unit of genetic code in a DNA or RNA molecule.
There are many different types of mutation. Here are a few: (Point Mutation, Substitution), Inversion, Insertion, Deletion, Duplication, Translocation Point mutation* – a change in one base in the DNA sequence.
Substitution *– when one or more bases in the sequence is replaced by the same number of bases
Inversion – a segment of a chromosome is reversed end to end
Insertion – when a base is added to the sequence (frame shift)
Deletion – when a base is removed from the sequence (frame shift)
Duplication - portion of genetic material or chromosome is duplicated, resulting in multiple copies of that region
Translocation - rearrangement of part or all of a chromosome to a different chromosome