A mutation is an abnormality in the DNA structure of an individual. Mutations can take place on different scales; the smallest mutation being called a point mutation which happens when base pairs on the DNA pair up with the wrong ‘partner’. Not all mutations are harmful. Many mutations are beneficial and our survival and that of most other creatures on the planet depend on mutations happening. Mutations can be caused over a period of one’s life by exposure to various types of radiation or when the DNA makes a mistake during its replication often in the stage of cell division, referred to as mitosis, where the cell nucleus divides and replicated all the genetic material within it.
Mutations can be hereditary. There can be mutations which alter a whole chromosome or part of a chromosome, in the case of for example Down’s syndrome which results when an individual has an extra chromosome, thus have a total of 47 instead of 46- the normal number of chromosomes in an individual. Occasionally, during a DNA paternity test, there can be a mis-match between father and child alleles, this usually happens when there is a mutation and can be confusing to parents trying to understand the results.