How much DNA in FIRs (Fully Identical Regions) do relatives share?

Note: see here for a collection of links to Sim-cM-related pages. When we find a DNA match between two people, one way we can attempt to understand their relationship is to evaluate the amount of DNA shared. Resources such as The Shared cM Project, and DNA Painter’s relationship probability tool allow us to quickly evaluate the likelihood... Continue Reading →

Sim-cM: An Update

A couple of weeks ago, I introduced Sim-cM - a project aiming to provide data from simulated pedigrees for different relationships of genealogical interest. I have now added more data, with results posted for 66 different relationships (including all of those listed in the Shared cM Project Version 3.0). For each relationship, I have included:... Continue Reading →

A New Project: Sim-cM

I've been working on a project to simulate pedigrees and calculate the amounts of DNA shared between pairs of computer-generated relatives in different relationships. Using the Ped-sim Pedigree Simulator,1 I've generated data for eight relationships so far, with 10,000 simulated pairs of relatives apiece.  The main page for Sim-cM has summaries of the results that... Continue Reading →

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