Joan, I am sorry but I am not an expert on the testing methods that are used by 23andme as well as their test loci, etc. But I can give you some feedback on the state of testing by most other current sites. I know of none of them using any loci located on the X or Y ("sex") chromosomes for AUTOSOMAL testing, so I am not going to comment on your "Find" beyond stating that it surprises me that 23andme does use those chromosome in their autosomal testing, IF, in fact, you are correct in your statements. Autosomal testing is NOT the same as Y-DNA testing. It is also not the same as my-DNA testing. Perhaps you have them confused? I don't know, but assuming what you are saying is correct, I would say that you have some fairly interesting miracles going on there that someone might want to study. Dave ====================================== Date: Sat, 19 May 2012 14:53:10 -0400 (EDT) From: JYoung6180@aol.com Subject: Re: [ROOTS-L] Are You kidding me??? To: odinaz@comcast.net, Roots-L@rootsweb.com, nelda_percival@hotmail.com Message-ID: <9a66.582dafc6.3ce94616@aol.com> Content-Type: text/plain; charset="US-ASCII" Well...I can tell you that I found a mother and son (I'm her 2nd cousin once removed and he's my 3rd cousin) and our total percentage of match is slightly less than 2% (23andme's relative finder said we were both probable 3rd cousins). However, we all match just about completely on an X chromosome The X my 3rd cousin got from his mother and the one I got from my father match very very closely. We have other matching segments of autosomal DNA but those are tiny segments in comparison to our X matches. Of course X like other sex-linked DNA (Y and mtDNA) is inherited intact from one parent of the other. The problem with X is figuring out (for females like me at least) WHICH of the 2 Xes came from which parent. My cousins' paper trail and mine prove out exactly where each one came from. If I ever had any doubt as to paternity (I didn't but just saying) the X match verifies it in this case. Joan