Start A most accomodating nephew

A most accomodating nephew

This has happened when there are two good sized matching segments but each segment is from a different ancestral couple.

This is why I prefer to look at matches that are “phased” that is to say a child and a parent have the same match. based on Blaine Bettinger’s lastest chart at: https://dnapainter.com/tools/sharedcm that will show you all the possibilities for the shared c Ms.

If you only match someone on a single good sized segment (greater than 10 c M for most, more than 20 c M for the endogamous) your DNA relative can be anywhere from a 4th to a 14th cousin. Then you can use the ages of the testers plus test more relatives to try to figure it out.

Conversely, he inherited less DNA shared with Dick’s mother from his other grandparents.

I have sometimes found that someone predicted to be a 3rd/4th cousin based on total c Ms is much more distant.

The amount he shares with each 2nd cousin is practically identical, as long as you subtract the 40 c M that he shares with John on the X from the total shown by 23andme.

Amazing how variable DNA inheritance can be among 2nd cousins.

Click here for the ISOGG wiki article on Autosomal DNA statistics which usually includes the current chart from Blaine Bettinger’s shared centimorgan DNA project.