Evaluation of the match probability between a DNA sample from an innocent suspect and DNA from the scene of the crime is one of the controversial aspects of presenting DNA evidence in court. Calculating the frequency of the DNA profile of a randomly chosen person from the population involves statistical problems and problems linked to the genetics of the human population. The frequency of this profile is used in the calculation of the value of the evidence - the declared match between the DNA profile of the suspect and the DNA profile of the biological trace taken at the scene of the crime. This frequency is influenced by the racial differentiation of the population and the possibility that the innocent suspect and perpetrator are related to a varying degree.