The invention provides a method for obtaining additional information about DNA mixtures arising from a variety of sources and/or a variety of concentrations. In particular, the invention provides a method for indicating the likelihood that a DNA mixture arose from sources of a defined type where: the DNA mixture is formed by DNA samples from more than one source, the method involving the determination of the identity of the alleles present at a locus for the DNA in the mixture; determining a first probability function for the situation where the DNA mixture is formed from samples arising from the given person and from a first other person; determining a second probability function for the situation where the DNA mixture is formed from samples arising from a second other person and a first other person; using the first probability function as numerator and the second probability function as denominator in determining a likelihood ratio for the mixture having arisen from the defined type of sources considered in the first probability function; determining such likelihood ratios for a plurality of loci; and combining the likelihood ratios to give a combined likelihood ratio for the mixture having arisen from the defined type of sources considered in the first probability function.