DNA analysis can be complicated when one doesn’t know too much about their tree. Those of us who have ancestors who for generations lived in a rural area or a small tight-knit community have at least two additional issues that can compound the analysis of our matches:
- the number of people to we are related in more than one way–with relationships close enough that it can impact autosomal DNA results;
- the number of people where I and Bob are both related to A–but in different ways. Bob, A, and I don’t share any common ancestors.
When there are gaps in your tree, these issues can make people appear to be related in ways they are not when analyzing DNA matches.
For a little more read my longer post on “Another Confusing Set of Shared DNA Matches.”