What effect does a somatic mutation typically have?

A somatic mutation occurs in non-germline cells, meaning it takes place in the body cells rather than in the reproductive cells (sperm or egg cells). As a result, somatic mutations typically only affect the individual in which they occur. These mutations can result from environmental factors like UV radiation or can occur spontaneously during DNA replication. Since somatic mutations are not present in the germ cells, they cannot be passed on to offspring, distinguishing them from germline mutations, which do have hereditary potential.

While somatic mutations can sometimes lead to diseases such as cancer, this is not universally true, as many somatic mutations may have no significant effect on the individual. Thus, the impact of these mutations varies widely, but fundamentally, they are confined to the individual organism in which they arise.