Genetic tests provide an estimate of the probability that the testees have a Most Recent Common Ancestor (MRCA) within a useful range of time. The DNA test measures lengths of certain specific sequences on the Y chromosome. By comparing these lengths for different test subjects, a determination of how closely the testees are related. The Y chromosome occurs only in males and is passed down more-or-less unchanged from father to son, making this a very powerful for genealogical purposes. Females may participate by having a close male relative (father, brother or son) to provide a sample.
A genetic test kit consists of a cheek scraper and a collection tube. The cheek scraper is used to collect a sample from inside the cheek (about the same as using a soft bristle toothbrush). The YNGHA encourages all eligible Yarbroughs to take a 37-marker DNA test although the 67-marker test is much more accurate and is prefereable if cost is not a factor. It should be noted that the testing laboratory offers discounted tests from time to time. Notices about such opportunities are posted by the Project coodinator and by this site as they occur.
Yarbrough Family DNA Project Results
The project results are updated periodically by the Yarbrough DNA Project Coordinator,
Please contact him about your participation in the project.
FamilyTreeDNA (ftDNA) provides the test results to the tested person, and to WorldFamilies. Each tested individual's test results includes a user ID and password that allows the tested individual to review his/her test results at the Family Tree site. Family Tree offers tested individuals the option of allowing their respective test results to be uploaded to the World Families database. The test results may also be uploaded to ySearch, a site that allows individuals to compare their respective DNA data to others with the same markers (not always of the same surname of the tested individual). The user name and password are also used for access to an individual's data at the World Families site.
The y-DNA test results are shown at the Yarbrough DNA Project site. DNA results from ftDNA are updated at WorldFamilies periodically and by the project coordinator as required.
The complexity of the science underlying DNA testing cannot be over-stated. It is a powerful genealogical tool, and a successful program requires as much data as is possible to obtain. The Yarbrough DNA pool of data is just now becoming large enough to be really useful. Thus, the necessity of having as many Yarbroughs as possible take the y-DNA test will continue to be emphasized for some time.
The Yarbrough DNA Project Patriarchs' page lists the pedigrees of tested individuals according to the earliest respective ancestor within several apparently distinct family groups. The Patriarch's page is also available at this site. These groupings are according to the matching of the various marker sets for the tested persons. As more individusls test results become available, these groupings may change to reflect the additional data. Thus, the importance of providing accurate pedigrees cannot be over-emphasized. There is always the risk that a particular family lineage data may be taken as authoritative, when in reality it may be flawed. The project coordinators reserve the right to correct any submitted lineage data that is submitted.
Frequent Questions About DNA Testing
Visitors to the YNGHA Facebook page have raised questions about what happens to DNA data after the test lab has sent results to the tested individal (or surrogate). The more pertinent of these are:
- Are there other vendors out there that people are using?
There are a number other genealogical DNA testing firms, including 23andme, AncestryDNA (an Ancestry.com), AncestrybyDNA, Britains-DNA, DNAme, DNA Worldwide (FTDNA affiliate),Genebase, 23andme, Roots for Real, YSEQ, among others. In addition, other DNA testing labs may (but not necessarily will) provide test results that can be uploaded to the database of the user's choice.
- What happens to the results?
Typically, the results are sent to the tested person. It is up to that person to contact the database administrator (WorldFamilies, GEDMatch, etc.) and upload his/her test results. Generally, the submitter chooses between private and public viewing of the data. In the case of the Yarbrough DNA Project, the test subject must authorize the display of his/her data with the y-DNA spreadsheet. Subject to this limitation, FamilyTreeDNA test data are automatically uploaded to ySearch (http:www.ysearch.org). This is a service provided by FTDNA that is more or less comparable to GEDmatch.
- If they're not using familytreedna, are the results transferable the Yarbrough DNA database?
Yes, and it can be either quite straight-forward or a bit more involved, depending upon the testing lab. There are several sets of test data in the Project database that originated from labs other than FamilyTreeDNA.
- Do we have a female Yarbrough database?
Not as such, and the mitochrondial results address an entirely different set of conditions. That is, the mtdna shows maternal connections but not the relationships. For those, one must rely on y-DNA tests of a maternal ancestor's nearest male relative. Another way of saying it, the mtdna just isn't that useful for establishing relationships, however interesting it may be.