And if anyone wants to see the results that we have received so far for the participants in the Alexander DNA project, we invite you to take a look at the web site at http://alexanderdna.org/http://alexanderdna.org/. You won't see 100 participants because we haven't received laboratory reports from all yet.
As Roger said, we are one of the larger family projects. The members, who live mostly in the U. S., belong to more than 30 groups that have been genetically separated from each other for at least as long as their surname has been Alexander, often much longer. About a dozen of these 30 groups have two or more members while the remainder have not yet found anyone else as part of their family group among the DNA testers.
Within a group having several members, the tests on YDNA, which is inherited only from father to son, show no variation or very little variation from person to person; however, the difference in YDNA between a person from one group and a person from another group is usually extremely great. If a person's test includes sufficient "markers" (at least 25 with more being better) there is usually no difficulty in determining whether the person belongs to a particular family group.
If you are undecided about using DNA testing to help find your Alexander ancestors, take a look at the web site. It has the YDNA profile for each project participant, the family grouping of participants, the known Alexander lineage for many participants, and contact information (including a link to Roger) for learning more about the project and how you can join. Please note that YDNA is passed only from father to son; so, if you are a female who wants to trace your Alexanders, you must get a father, a brother, or a male Alexander cousin to take the test for you.