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Estimation of Y haplotype frequencies with lower order dependencies

NCJ Number
Forensic Science International-Genetics Volume: 46 Dated: 2020
Date Published

This article reports on a new model for Y STR haplotype population frequency estimation.


Estimating Y haplotype population frequencies is a demanding task in forensic genetics. Despite the suggestion of various methods, none of these have yet reached a level of accuracy and precision that is acceptable to the forensic genetics community. At the basis of this problem is the complex dependency structure between the involved STR loci. The current project approximated this structure using specific graphical models, namely t-cherry junction trees. Researchers applied trees of order three by which dependencies between three STR loci can be taken into account, thereby extending the Chow–Liu method, which is restricted to pairwise dependencies. The t-cherry tree method outperformed the Chow–Liu method as well as the well-established discrete Laplace method in estimation accuracy. (publisher abstract modified)

Date Published: January 1, 2020