Mutation Is The Original Source Of Genetic VariationMutations alter the DNA sequence, creating new alleles.New alleles introduce variation within a population.Without mutation, all individuals would be genetically identical, leaving nothing for natural selection to act on.DefinitionSee other references2MutationA mutation is a change in the DNA sequence, which can alter the instructions for building proteins or regulating cellular processes.New Alleles Are Raw Material For EvolutionMutation supplies the variation, and the environment then decides which alleles spread.A new allele that improves survival or reproduction becomes more common over generations.Most mutations are neutral or harmful, so beneficial ones are rare but important.New alleles are created from altered phenotypes due to mutationsExampleIn a forest of mostly green beetles, a few are brown due to a mutation.A fire darkens the forest floor, so the brown beetles are now better camouflaged.They survive and reproduce more, so the brown allele becomes more common.Practical Use: Reading Variation Through Genetic TestingModern technology can detect mutations in our DNA through genetic testing.These tests can reveal:Disease risk: variants in genes like BRCA1 can raise the risk of cancer.Ancestry: SNPs can trace genetic heritage.Trait prediction: some variants predict traits like lactose tolerance or eye color.Theory of KnowledgeHow should societies balance the benefits of genetic testing against the risk of misuse or misunderstanding?The Balance Mutation CreatesVariation is a trade-off: the same process that causes disease also fuels adaptation.A population with more variation is better able to survive environmental change.Active recallHow do mutations create new alleles?Why would a population with no mutations be unable to adapt?In the beetle example, why did the brown allele become more common?Name two things a genetic test can reveal about a person's DNA.
