In a strict sense, mutations are changes in genes not caused by genetic recombination. A change in the base sequence of DNA, for example, represents a mutational change. Spontaneous mutations are mutations that occur at a given frequency without the need for an inducing agent of change (mutagenic agent). The term mutation is also used in a less technical sense to describe changes in the human genome (i.e., evolution) that result from a broad spectrum of processes that act to increase or decrease genetic variation within a population.

By definition, a gene is a hereditary unit that carries information used to construct proteins via the processes of transcription and translation. The human gene pool is the set of all genes carried within the human population. Genetic changes, including mutations, can be beneficial, neutral or deleterious. In general, mutations, along...