State of the Art for Microhaplotypes

In recent years, the number of publications on microhaplotypes has averaged more than a dozen papers annually. Many have contributed to a significant increase in the number of highly polymorphic microhaplotype loci. This increase allows microhaplotypes to be very informative in four main areas of forensic uses of DNA: individualization, ancestry inference, kinship analysis, and mixture deconvolution. The random match Probability (RMP) can be as small as 10⁻¹⁰⁰ for a large panel of microhaplotypes. It is possible to measure the heterozygosity of an MH as the effective number of alleles (A_e). A_e > 7.5 exists for African populations and >4.5 exists for Native American populations for a smaller panel of two dozen selected microhaplotypes. Using STRUCTURE, at least 10 different ancestral clusters can be defined by microhaplotypes. The A_e for a locus is also identical to the Paternity Index (PI), the measure of how informative a locus will be in parentage testing. High A_e loci can also be useful in missing persons cases. Finally, high A_e microhaplotypes allow the near certainty of seeing multiple additional alleles in a mixture of two or more individuals in a DNA sample. In summary, a panel of higher A_e microhaplotypes can outperform the standard CODIS markers.