instagram pinterest linkedin facebook twitter goodreads

Genetic Linkage

A Common Ancestry Metric Is Based On a Century-Old Discovery by a 19-Year-Old: CentiMorgans Explained

I’ve been immersed in genetic genealogy, following up on a recent contact from a relative I didn’t know existed. While trying to imagine scenarios that might explain how we came to be connected, I contacted Ancestry.com for assistance in seeing actual data. When I found the obvious drop-down menus next to my matches on the website, I was astounded to recognize the unit used to assess the closeness of relationships – a centiMorgan.

I’m sure that’s Greek to most people. But to a former Drosophila (fruit fly) geneticist like me, “centiMorgan” (cM) brought an instant meaning: distance along a chromosome.

Invention of the centiMorgan is one of my favorite tales from the history of genetics. It provided the very first genetic map, and inspired the variations on the theme that were to come, including full genome sequencing.

The intuition that has sent millions of people googling centiMorgans, with more to come after all those DNA kits are opened and spat into for Christmas, goes back to a sleep-deprived 19-year-old with a fantastically brilliant idea, 105 years ago.

To continue reading go to DNA Science, my blog for Public Library of Science, where this article first appeared. Read More 
Be the first to comment