The two main sources of genetic variation are mutations and recombinations of genes as a result of sexual reproduction. A mutation is a permanent change in the DNA within a gene.Continue Reading
Some mutations, which affect all cells in an organism, are inherited from a parent. Other mutations develop during an organism's life and occur in only some cells. Mutations are not always harmful. For instance, although the disease sickle cell anemia is caused by a mutation, that modified DNA also helps prevent malaria in some people.
Sexual reproduction causes genetic variation because of three factors. During the cell division that produces eggs and sperm, genetic material is exchanged. When these sex cells are formed, chromosomes are assorted by chance. In addition, a random egg and sperm combine during fertilization.Learn more about Molecular Biology & DNA
Meiosis contributes to genetic variation by creating new groups of genes, according to the University of Miami Miller School of Medicine. The new groups are created when chromosomes passed down from a mother and father share instructions encoded into genes. The process of mixing genes leads to offspring with nearly unlimited possibilities for genetic instructions.Full Answer >
Disruptive selection tends to increase genetic variation in populations, according to About.com. It is the opposite of stabilizing selection, which tends to drive a population toward a mean genotype and eliminate outliers on either end of the population average.Full Answer >
Genetic recombination is the rearrangement of genes to produce offspring with different combinations of traits than either parent. Recombination is the source of genetic diversity in sexually reproducing organisms.Full Answer >
Genetic information is stored in several places, which are DNA molecules, genes, chromosomes, mitochondria and the genome. Different amounts and types of genetic information are stored in these locations. The majority of genetic information is stored within individual DNA molecules, although it is found in other cellular locations as well.Full Answer >