How is genetic distance calculated for NULL values?
For matching, genetic distance is calculated for someone with a NULL result using the value of zero. As part of the coming system upgrades, this will be brought in line with current science that considers NULL events rare but not necessarily meaning that two men are not related on their Y-chromosome lineage within the genealogical time frame. Once the upgrade is complete, a NULL value-causing event will be treated as a single step event with a genetic distance of one. This is how we recommend you evaluate your potential cousins within group projects.
