Mixtum: a graphical tool for two-way admixture analysis in population genetics based on f-statistics

TL;DR

Mixtum is a user-friendly tool for analyzing two-way admixture in populations using f-statistics and provides graphical and numerical results.

Contribution

Mixtum introduces a novel angle-based index to assess the quality of ancestral reconstructions in admixture models.

Findings

Mixtum estimates ancestry contributions using bi-allelic genotype data and f-statistics.

The tool provides interactive and graphical outputs for different admixture models.

A new angle-based index is introduced to evaluate the quality of ancestral reconstructions.

Abstract

Mixtum is a Python-based code that estimates ancestry contributions in a process of two-way admixture based on bi-allelic genotype data. The outcomes of Mixtum come from the geometric interpretation of the f-statistics formalism. Designed with user-friendliness as a priority, Mixtum allows to interactively handle a menu of user-supplied populations to build different mixture models in conjunction with the set of auxiliary populations required by the framework. The results are presented graphically and numerically. Importantly, Mixtum provides a novel index (an angle) that assesses the quality of the ancestral reconstruction of the model under scrutiny. The use and interpretation of the outcomes of Mixtum are explained and illustrated with case studies.

The open source code is available on GitHub at https://github.com/jmcastelo/mixtum and on Zenodo at https://doi.org/10.5281/zenodo.17789375. Mixtum is implemented in Python and runs on Linux, Windows and macOS.

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