Y-Haplogroup N3a with DYS437=15. Expert advice requested!

[Svein Davidsen]

I know this is a long entry, but stay with me to the end, may be you can help!

I have taken the Ethnoancestry Multiplex SNP test and have been confirmed as belonging to Haplogroup N3a (i.e. with mutations - M214 – LLY22/M231 – TAT – M178). I have also taken the Family Tree 37 marker STR test and the test results are on the FT “N Y Haplogroup Project” under N3115 and on ysearch.org under code SW7S9.

The N3 Haplogroup is not very common in southern Norway where my paternal family has lived for at least the last 8-9 generations, with less than 1% of the sampled population, but this is increased to over 10% in the northernmost counties of Norway and increases further to over 60% of the population in Finland. Searching the FT database for Haplotype matches this is reflected in a large number of 12/12 matches with people living, or with paternal ancestors, in Finland. In fact my first 12 markers, in the FT sequence, matches the “N3a” Modal values as calculated from the current “N Haplogroup Project” participants.

However, extending the search to 37 marker does not give me any really close matches at all. On FT the closest is one 29/37 match. On ysearch .org there are two 22/25 matches. On ybase.org there are two 23/37 matches, on yhrd.org there is one 11/11 match in Volot, Russia, and on smgf.org there are two 20/23 matches, one of which is in Finland.

The way I understand the TMRCA calculations the lack of any close matches means that I do not appear to have a common ancestor within several thousand years with any of the people tested so far.

In Norway, until 3-4 generations ago, surnames were patronymic so it is not much use looking in a Davidsen family project for distant relatives either.

An interesting point arises however, if I look at some of the STR markers where I do not match with other people. For example the DYS437 marker where I have the value of 15. On all the Haplogroup N databases I know of I can only find one other person with the same value, all the others have DYS437=14. The one person with DYS437=14 states his origin as Ireland, but unfortunately the overall match between us is only a 25/37 match with a genetic distance of 15, i.e. the MRCA is 1000’s of years distant.

Looking at http://hurlbutdna.pbwiki.com/DNA%20...utation%20Rates it states that DYS437 is a very “slow moving “ marker with, on the average, one mutation every 800 generations, i.e. say every 15-20,000 years.

Dr Spencer Wells in “Deep Ancestry” estimates the time of the LLY22G mutation, i.e. the start of Haplogroup N, to be within the last 10,000 years and Siiri Rootsi et al. in their EJHG (2006) article on Haplogroup N calculate the age of the N3 mutation, TAT, to 11.8 +/- 6.8 Ky ago. They do not have a date for the N3a mutation, M178, but that obviously must be even later, i.e. closer to the present time than the average mutation time for the DYS437 marker.

My interpretation of this, with regard to the DYS437 marker, is that the original DYS437 marker allele value was probably 14. In the majority of N3a males, DYS437 has not changed since the time of the M178 mutation, but somewhere in my own paternal ancestry, possibly even with me, it mutated to the value 15. The main reason for not finding any matches for this marker is because it is a recent event and too few N3a people in southern Norway, or anywhere else for that matter, have tested for this marker to-date. For example Berit M Dupuy et al in their 2005 article “Geographical heterogeneity of Y-chromosomal lineages in Norway” did not test for this marker.

For other slow moving markers, e.g. DYS454, 455 and 448 I have a 100% match on the various N databases, i.e. these markers have not changed since the M178 mutation, whenever that was.

There is another explanation of course and that is that my test results are wrong and that I also have DYS437=14!

Can any of you experts out there tell me if I have made any fundamental error(s) in my “research” and reasoning before I start to use brute force on my male paternal relatives to get them to take the STR test to confirm the Haplotype markers? Or are there databases I don’t know about that can move my search forward?

All suggestions thankfully received.

[lgmayka]

The way I understand the TMRCA calculations the lack of any close matches means that I do not appear to have a common ancestor within several thousand years with any of the people tested so far.

This is an exaggeration. Years ago, FTDNA was solely interested in genealogy, and so whenever a near-match was beyond the range of traditional genealogy (i.e., English-speaking surnames and land records), FTDNA would say 'thousands of years' in order to discourage some customers from needlessly bothering others with weak near-matches.

FTDNA's current position is better expressed by its FTDNATiP calculator, available on your Y-DNA Matches page for close matches and also available to a project administrator for any two members of her/his project. The calculator is actually criticized as perhaps too optimistic--i.e., based on unintentionally exaggerated mutation rates reported by customers.

Ysearch shows a couple of men who are 3 steps away from you at 25 markers, plus several men who are 11 steps away from you at 37 markers. However, keep in mind that for members of haplogroup N, genetic distance can be artificially exaggerated by the triple-doubling (actually a harmless deletion in part of the Y chromosome) which causes some single mutations to appear twice in FTDNA's presentation and computation of the haplotype.

You might try to persuade the two men who are 3 steps away at 25 markers to upgrade, at least to 37.

In any case, however, you should not be discouraged by a lack of close matches. This is actually the common case of a haplogroup that has not undergone a recent rapid expansion (e.g., due to imperialist colonization of another continent). I suggest that you encourage more descendants of your patrilineal ancestral village to get tested.