On Fri, 8 May 2009 10:29:59 -0700 (PDT), Q <quolla6@gmail.com> wrote: > In August I asked several questions about the new Ancestry YDNA > testing service. There were no substantive replies to the question > asked, though several replies indicated skepticism about the use of > YDNA. > > The question remains a matter of interest. In following up another > problem this morning I came across the Sorenson site which provides > a nice comparison of different YDNA testing services and the markers > used for a 37 marker test. > > http://www.smgf.org/ychromosome/marker_standards.jspx > > These data seem to be directed more toward systematic differences in > values assigned to the markers tested which seems to vary between > testing services. In many cases there's a direct conversion from > one service to another, but in other cases no conversion is known. > As a result, if you make certain choices as to testing service, > comparability with results from other testing services may be > difficult, or limited. > > The Sorenson data does not immediately answer the specific questions > asked. Vis-a-vis, Ancestry and FTDNA, the results look to be > generally comparable. If you did a 33 marker test on Ancestry per > their suggestion, it seems that it would be comparable with data > from a 37 marker test on FTDNA, though obviously you wouldn't be > able to compare results for the 4 markers not tested in Ancestry's > 33 marker test. I note that four markers (probably different from > the four excluded by Ancestry in the 33 marker test) require some > degree of conversion. > > Q Look at Family Tree DNA 37 marker test. Hugh Eagle@bellsouth.net (J. Hugh Sullivan)