The Effect of Pedigree Collapse on DNA Matching: A Case Study
Pedigree collapse occurs in a person’s family tree if one of their ancestral couples are related to each other. This causes the same ancestors to be repeated in their tree. For example, if a person’s parents are second cousins through their great-grandparents Joseph Dyer and Anna Smith, then Joseph Dyer and Anna Smith appear in the test taker’s pedigree twice. Instead of having 32 unique third-great-grandparents, this test taker has 28 unique third-great-grandparents. These diagrams...


