Tuesday, July 28, 2009

DNA Project Update March 19, 2009

DNA Project Update March 19, 2009

Last weekend I had the good fortune to attend the fifth annual conference of project administrators sponsored by Family Tree DNA in Houston. This is always a worthwhile event, and I’d like to share with all of you some of what I learned.

Websites: I’m sure most of you have already noticed that the FTDNA website has had a significant upgrade and is much easier to navigate and use. (Of course, the same is true of our World Families Network site.)

Haplogroups: The haplogroup tree (also known as phylogenetic tree or tree of mankind) is constantly growing as new SNPs are discovered. Some of you have had the Deep Clade test, which refines your individual placement on the tree (determines the subgroup to which you belong and, therefore, the smallest twig so far identified on your branch). To explore where you now are placed, go to your personal page at FTDNA and click on the Haplotree tab. There are also advanced tests to further refine your placement in subgroups. There is a bit of overlap among the various panels of Advanced Tests now, but this is undergoing careful examination and will be minimized if not eliminated soon.

Some of the advanced tests can be helpful in establishing break points in lineages in order to assign descendants within a family to a specific common ancestor.

Projects: Effective immediately, everyone tested at Family Tree DNA may join as many projects as he or she wishes. (Click the Join tab on your personal page and scroll through the options.) You are certainly encouraged to join your haplogroup project, of course, since you can only match someone who has the same haplogroup that you do.

You may also join geographic projects that interest you. For example, if you have German roots, you may want to join the Germany-DNA and the Colonial German DNA project as well as the Palatine project if you fit within the parameters of all three groups. Or join the British Isles and Lancashire groups if that is your place of origin.

Of course, the surname project continues to be the primary project for everyone if one exists for your name. Remember to look for alternative spellings too.

Legal Concerns: Legislation has been passed in California, New York and Maryland that prevents the sale of DNA kits direct to consumers. They require that a medical professional place the order. More legislation is threatened in other states. FTDNA is working with authorities to help disassociate genealogical testing from medical testing. There is much confusion among the public, which often does not distinguish between them. As you know, genealogical testing is not autosomal testing. That is, it does not deal with 22 of the 23 chromosomes we inherit from each parent. We look only at the non-recombining 23rd chromosome, the Y chromosome for men and the mitochondria for women.

The position that we project administrators all agree on is that we should not be prevented from learning as much as we wish about ourselves. A genealogical DNA test is certainly less revealing than a paternity test or, indeed, a pregnancy test, both of which are readily available over the counter. Results from these can produce far more anguish than dealing with ancestry issues in most cases. A bill was introduced in Congress, but it is not actively being considered now. Most proposed legislation is aimed at companies like 23andMe and DeCodeMe that are medically oriented and test the other 22 chromosomes, but there is a potential risk for confusion between them and Family Tree DNA.

Testing Standards: FTDNA has always worked closely with the National Institute of Standards, which has finally taken a position that should help to standardize test results nomenclature across testing companies. Some labs have always taken a proprietary approach, and they may continue to do so, but standards are now in place. Each of you may see some of your marker values change over the coming weeks as FTDNA implements changes to three of its markers. This does not mean there is any underlying change, only in the nomenclature.

National Geographic/Genographic Project: This project will continue to recruit participants until sometime next year. At that time, they will destroy all samples submitted to them. If you know anyone who has tested with National Geographic, be sure to encourage them to authorize their transfer to Family Tree DNA to allow future testing. As you may know, FTDNA does all the testing for this project. Therefore, they have physical possession of the samples to be destroyed. Transfer to FTDNA’s repository is therefore FREE and very simple to accomplish. The testee simply signs into his page at National Geographic/Genographic, scrolls to the bottom of the page where it says “More information…”, clicks on it and finds the link to authorize transfer.

All of you who have already tested with FTDNA may have your results added to the National Geographic Project for a charge of $15. This allows you to contribute to this major population study, which I highly recommend. The option to allow you to do this is on your personal page at FTDNA.

About mtDNA: As we all know, it is extremely difficult to trace a maternal lineage because the surname changes every generation. The mtDNA test has been less than useful genealogically because mtDNA mutates so slowly. HVR I reveals one mutation per 20,000 years! The one significant factor is “private SNPs” which can only be discovered in the FGS (Full Genetic Sequence) test. The FGS mutation rate is one per 4,000 years. FTDNA now has 4100 FGS test results in its database. When uploaded to GenBank, these results are an extremely valuable resource for geneticists and population scientists.

Work in Progress: A “walk through the Y” is a new offering that is still experimental. It is a way to participate in advanced testing that is expected to yield new SNPs within haplogroups but geared to specific subgroups of people who might benefit from a deep analysis of the Y. At a cost of $750, it is not expected to attract large numbers of people, but we will watch carefully as work continues.

The lab is working to develop a new “maximum likelihood” estimated TMRCA (time to most recent common ancestor). Needed are four-generation volunteers and groups of close relatives who all have tested to 67 markers. If anyone is interested in participating, please let me know. The goal is to build a better model taking into account variable mutation rates, asymmetry, multiple steps, and allele-specifity. We were reminded that the present method of estimating TMRCA is highly useful for unknown single events, but is much less so where a pedigree is known from traditional genealogy. In other words, just because a TMRCA estimate suggests a difference of many generations, we should always consider the paper trail as equally important. We should not apply the probabilities to known events.

Ysearch will be redesigned this year. (Everyone should automatically upload his results from his personal page every time he receives any new test results.) For now, you can add any advanced marker results in the Comments field.

Miscellaneous: Some of you have asked what the DYS numbers mean in your test results. They are meaningless for all practical purposes and represent the order in which a particular marker was discovered. Similarly, the names of Sub Haplogroups are formed from the first letter of the laboratory that discovered the SNP and the sequential number of the discovery within that lab.

Another question that arises sometimes is, What is the difference between a SNP and a STR. The STR (Short Tandem Repeat) is equivalent to DYS numbers (DNA Y-chromosome Segment), the markers we all know and love; a SNP (Single Nucleotide Polymorphism) refers to the entities tested to refine haplogroup placement. (Aren’t you glad you asked? GRIN)

If I think of anything else, I’ll write again. Questions are always welcome. Write anytime!

Best regards,
http://freepages.genealogy.rootsweb.com/~dorisw (personal website)

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