Genetic mutation

Genetic mutation- this term indicates an alteration to base sequence in DNA of an organism which results in a mutant allele of a gene i.e. an allele that occurs in less than 1% of population. The change is heritable and can be passed on to offspring if fixed into the parental genome. Mutations can vary depending on the type of genomic alteration:

• addition
• deletion
• substitution
• rearrangement of bases.

To investigate the events leading to mutation we can look at the 3 types of mutagenesis process:

• spontaneous (no mutation causing agent)
• induced (a foreign genome introduced e.g.in the laboratory)
• directed (in vitro change to the genome).

We can calculate the rate of mutation occurance using an equation from Poisson distribution:

P₀=e^-mN

where P₀ is the probability of seeing no mutations, N is the number of cells per culture and m is the mutation rate .