15.6 xDNA Testing

Because it is connected to the man’s maternal line, the xDNA inheritance pattern is complex. Expanded DNA (xDNA) is not actually tested on its own but is part of atDNA testing. Unfortunately, xDNA is not reported in the results of all atDNA testing companies.1 This type of testing can be helpful to some research projects but will not be explored in this text. Researchers can find more information by consulting the sources cited in the footnotes of this chapter.2