The following is an excerpt.
When genetic counselors attend family reunions, their unofficial job becomes Namer-of-Relationships. “Keith, you and I are first cousins once-removed. Viola is my great aunt. Margo, you are my mother’s second cousin’s second wife so you would be…..well, some kind of in-law or kissing cousin, I guess.” It gets confusing, even for experts. It is even more difficult for patients or referring providers who try to relate a family history of a second cousin with a cleft palate and a heart defect but who is actually a first cousin once-removed.
Below I have created a generic pedigree that illustrates the most common familial relationships in the kinship system of the modern Western English-speaking world. The pedigree undoubtedly contains errors and omissions. So, in the spirit of crowd sourcing, I encourage my fellow pedigree wonks to scrutinize it and report mistakes, mislabelings, missing relatives, and thoughtful commentary in the Comments section below (this would also be a great discussion topic for a few hours of a genetic counseling student seminar).
View the original article here: And Bob’s Your Uncle: A Guide To Defining Great Aunts, Great-Great Grandparents, First Cousins Once-Removed, and Other Kinfolk
