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An experimental extension to the discrete Laplace method for Y-STR haplotype frequency estimation

NCJ Number
Forensic Science International Genetics Supplement Series Volume: 8 Dated: 2022 Pages: 237-238
Date Published
2 pages

In this paper, the authors propose a small extension to the discrete Laplace method that allows to model the full haplotype; their generalization of the method relaxes the limitation of requiring that all haplotypes should consist only of integer alleles at all loci.


Frequency estimation for Y-STR haplotypes is a challenging problem because limited data are available and complex dependencies exist within the data. As a result, various statistical methods have been proposed for frequency estimation. The discrete Laplace method has been recommended in some contexts by the DNA commission of the ISFG. This method is limited to haplotypes with single integer repeat alleles only at all loci. The authors propose a generalization of the method that handles duplicated loci such as DYS385 and less common alleles that are not integer repeats. The extension is implemented in an experimental R package called disclapmix2. Publisher Abstract Provided

Date Published: January 1, 2022