Relatedness inference using IBDhalf

This app allows you to interactively assign relationship labels to pairs of individuals, based on IBD statistics.

Following Henn et al. (2012), IBDhalf is defined as the total length of genomic segments (of at least 5 cM) where two individuals share DNA identical by state for at least one of the homologous chromosomes.

The plot on the left shows pairs of individuals as points, with their log10(IBDhalf) value on the x-axis and the number of shared segments on the y-axis. Use the dropdown to choose the relationship category, then drag a rectangle to assign it to a group of points. Assigned relationships are color-coded on the plot, and you can see a preview of the generated CSV output below the dropdown.

Figure 3A from Henn et al. (2012) illustrates expectations from their simulations.

The data are the test data from 2026 GHIST Relatedness Challenge 1. Once you're satisfied with your assignments, you can download the CSV file for submission.