Courtesy of Pixabay Mystery Match - What To Do Next You've checked your DNA results, possibly at a new test company, and you find an unfamiliar match sharing a large segment of DNA. While some of the companies assign a relationship, "1C,2R", that may not be accurate due to variables such as "half" siblings or cousins.  There are several tools available to help calculate relationships; one we have seen in presentations and online is the Shared cM Project 4.0 Tool v4.  https://dnapainter.com/tools/sharedcmv4 You can locate yourself in the white square marked "Self" just off the center.  Relationships that share, or are descendants of one or both of your parents are in light or blue gray.  Relationships with which the most recent common ancestor (MRCA) is one or both grandparents are in green, great-grandparents are in orange. The numbers in the squares represent the average shared cMs for that relationship as well as the low and high range.  Notice that

  Peter Calver of LostCousins has a new edition of his DNA Masterclass . If you don't use LostCousins, you are missing out! And you don't even need DNA results for that. If you have UK or Canadian ancestry, you really do need to add as many ancestors and cousins to LostCousins as possible, if you want to connect with British cousins. Distant Cousins are Gold In this Masterclass, Mr. Calver points out how important distant cousins will be to you. He published a chart I've not seen before: Based on Table 2 from: Henn BM, Hon L, Macpherson JM, Eriksson N, Saxonov S, Pe'er I, et al. (2012) Cryptic Distant Relatives Are Common in Both Isolated and Cosmopolitan Genetic Samples. PLoS ONE 7(4): e34267. doi:10.1371/journal.pone.0034267 Revised using Ancestry DNA estimates for the chances of detecting cousins and the expected number of 1st to 6th cousins for those of British ancestry; the numbers for 7th to 10th cousins are my own guesstimates Calver leaves out steps that I do on