HLAfreq: Download and combine HLA allele frequency data

The Allele Frequency Net Database contains publicly available data on human immune gene frequencies for different populations from a variety of sources. We introduce a python package HLAfreq to download, combine, and analyse this data. In particular, HLAfreq can combine multiple datasets and/or prior knowledge to improve allele frequency estimates and produce credible intervals. We demonstrate these features using real world data to visualise allele frequencies and compare populations. HLAfreq is hosted at www.github.com/Vaccitech/HLAfreq/ with documentation and detailed examples.