A year ago in this space, I
lamented the differences in Y-STR nomenclature that existed on
several markers between genetic genealogy companies. Since that time, things have only gotten
worse as some markers that were previously scored the same by all companies,
now have differences. Most companies
appear to be trying to do what they believe fits best with the recommendations
of the International Society of Forensic Genetics (ISFG), but there are
apparently differing interpretations of these guidelines. In addition, a few companies have standards
on a few markers that pre-date the general acceptance of the ISFG
recommendations.
In this issue of JoGG, the Human
Identity Group at NIST, led by John Butler, has written a review article on
Y-STR nomenclature that tries to explain
the basis for the differing interpretations (Butler, 2008). Perhaps more importantly, the group is now
providing its own recommendations for the markers where differing scoring
methods exist between companies. This
could well be a turning point in the history of this messy subject. We can only hope that now all of the
different companies will adopt the NIST recommendations and bring an end to the
confusion.
Undoubtedly, if these recommendations
are adopted industry wide, the change to the new standards will bring its own
confusion at first as we try to get used to seeing a new range of values being
reported from our favorite companies, but this should only be a temporary
problem. There will probably be temporary
confusion in the public databases as well, though it should be possible for
each database administrator to make a blanket change to all records in order to
bring them into line with the new standards.
The advantages of having
industry-wide standards are compelling for both buyers and sellers of genetic
genealogy services. The advantages for
consumers are obvious, but the confusion caused by differing standards may be
causing a small number of people to opt out of testing altogether. Probably more important for companies is the amount of time that a company must spend on
explaining why its results may be different from those of another company. It seems that both customers and companies
would benefit considerably from uniform standards.
Now that we have some clear
recommendations on the specific markers where there are differences between
companies, the ball is in the court of the genetic genealogy companies. Let’s hope that they will do the right
thing. It would be helpful if they could
coordinate the date for any changes that they may adopt.
Whit Athey
References
Butler JM, Kline MC, Decker AE
(2008) Addressing Y-chromosome short
tandem repeat (Y-STR) allele
nomenclature. J Genet Geneal, 4:125-148.