ISOGG wiki entry for Triangulation

Triangulation

• When three people all match each other at the same autosomal DNA location we call it Triangulation.

• From ISOGG: "If you have at least three people with a common ancestor matching on the same segment then you can infer that the segment came from that ancestor. "

• Inversely, if three people all match each other on the same segment then you can infer they have a common ancestor.

George

Anna

Anton

Anna

Henry

KRISTINE v my cousins

Kristine compared to Mike and John on chromosome 11

John
versus
Mike

Chr 11

Kristine compared to John, George and Henry

John versus 2nd cousins
George (PG) and Henry

Chr 14

Kristine compared to Mike and Katy

Mike
versus
Katy

Chr 16

Gunnar versus my Dad

Gunnar versus my Dad

Gunnar versus my brother

Top matches Dad has in common with Gunnar

Gunnar versus Kitty, no match on 2, match on 20

Dad's Matrix Matches

Automated Triangulation Tool at GEDmatch.com

GEDmatch triangulation sorted by chromosome location

Gedmatch Triangulation for Dad sorted by Match Name

Cousin Katy

Blog.KittyCooper.com