Selecting Microhaplotypes Optimized for Different Purposes

Massively parallel sequencing is transforming forensic work by allowing various useful forensic markers, such as STRPs and SNPs, to be multiplexed, providing information on ancestry, individual and familial identification, phenotypes for eye/hair/skin pigmentation, and the deconvolution of mixtures. Microhaplotypes also become feasible with massively parallel sequencing. These are DNA segments (smaller than 300 nucleotides) that are selected to contain multiple SNPs unambiguously defining three or more haplotype alleles occurring at common frequencies. The physical extent of a microhaplotype can thus be covered by a single sequence read, making these loci phase-known codominant genetic systems. Such microhaplotypes supply significantly more information than a single SNP. The project's efforts to develop useful sets of microhaplotypes have already identified 182 such loci that the project has studied on a large number of human populations from around the world. (publisher abstract modified)