1. ## YFull STR matches

The YFull FAQ on STR interpretations/matches says "close matches are matches with a genetic distance of less than 0.1, and distant matches are matches with genetic distance of 0.1 to 0.2."
At the moment I have one "close" match. It's calculated to be a genetic distance of 0.028, or 11/389.
Can anyone with one or more close STR matches at YFull as well as some knowledge of relationship, such as 6th or 10th cousin, comment on how close a relationship exists for 0.028?

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3. Very close... This is approximately if it were 3/111 distance by ftdna. I think empirical ~350-400 ybp. For accurate calculation, it is necessary to know the mutation rates of each marker from those 389.

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5. You can use the McDonald TMRCA calculator: http://www.scs.illinois.edu/~mcdonald/tmrca.htm and fill in the amount of markers, the non-matching markers according to the infinite alleles method (any difference is only counted as 1, which is actually used by Yfull) and guess a mutation rate. You can use the one for Y111 (0.0026) as an estimate.

11 out of 389 is between 2 and 9 generations ago with 90% confidence (if we assume the mutation rate of 0.0026 holds for 500 markers and 31 years per generation)

For reference, I have a match of 11 out of 426 that has a SNP-based TMRCA of 200 YBP and the shared ancestor was actually born in 1766.

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7. Originally Posted by gstockman
The YFull FAQ on STR interpretations/matches says "close matches are matches with a genetic distance of less than 0.1, and distant matches are matches with genetic distance of 0.1 to 0.2."
At the moment I have one "close" match. It's calculated to be a genetic distance of 0.028, or 11/389.
Can anyone with one or more close STR matches at YFull as well as some knowledge of relationship, such as 6th or 10th cousin, comment on how close a relationship exists for 0.028?
In my case, a Kit [B] with genealogical MRCA born 1606 is GD 3/111 and 9/327 with my Kit [A].
With the same surname I have another close match [Kit C] with GD 4/111 and 19/353 and I'm trying to guess when our MRCA was born.
Considering the common 304 STRs out of 500 STRs for the 3 BIG Y Kits, I have:
KITs A&B: difference 9/304 => genealogical MRCA 1606
KITs A&C: difference 14/304 => genealogical MRCA ??
KITs B&C: difference 15/304 => genealogical MRCA ??
By the way it seems to me YFull counts as GD = 1 a STR differing 2 (eg: 25 vs 27)

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9. A case study on the 111 marker test that may be helpful

http://linealarboretum.blogspot.com/...better-at.html

CONCLUSION

While 111 markers aided in fine tuning our connectivity to those sharing our genetic and genealogical roots, genetic distance was not an accurate predictor of most relationships. Outliers can and do happen, as experienced with a GD=0; however, 78% of the participants at a GD=0 fell within the predicted level of six generations or less with a p ≤ .01, Two did not, and as explained earlier, this was due to convergence. We have seen close relatives (5th cousins and closer) having genetic distances up to 5, while 13th cousins, once removed have a GD=0.

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11. I have zero close matches, the closest distant match is:

Compared STRs: 352
Differences: 38
Distance: 0.108

How close/far is that?

12. The STR results for my VCF shows the closest match at 31 difference in 230 compared STRs which has a distance of 0.135.

I've used the TRMCA Calculator referred in this thread and and the bars show between 12 and 29 generation.
Assuming worst case which is 29th generation and again assuming 31 years per generation I got ~900 years.

Is this calculation true for TMRCA?

And my second question; when my BAM file is full processed, is it more likely to have a close match?

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sgdavies@hotmail.com (07-17-2018)

14. Originally Posted by alhan

I've used the TRMCA Calculator referred in this thread and and the bars show between 12 and 29 generation.
Assuming worst case which is 29th generation and again assuming 31 years per generation I got ~900 years.

Is this calculation true for TMRCA?

And my second question; when my BAM file is full processed, is it more likely to have a close match?
The calculation only holds if we can assume the mutation rate of Y111 is usable for all Yfull STRs. I'm pretty sure that is not the case and likely many of the Yfull STRs are slower than Y111. So the true TMRCA will be longer ago. But it's a first guess to getting a TMRCA from all Yfull STRs.

When your bam is fully processed I will expect that some close STR matches will disappear as a lot of the faster mutating STRs will become available and push the Genetic Distance beyond the threshold of 0.1 (faster mutating STRs generally have a larger number of repeats, which are more difficult to measure).

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16. No close matches. Closest distant 272 38 0.14

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18. Originally Posted by gotten
The calculation only holds if we can assume the mutation rate of Y111 is usable for all Yfull STRs. I'm pretty sure that is not the case and likely many of the Yfull STRs are slower than Y111. So the true TMRCA will be longer ago. But it's a first guess to getting a TMRCA from all Yfull STRs.

When your bam is fully processed I will expect that some close STR matches will disappear as a lot of the faster mutating STRs will become available and push the Genetic Distance beyond the threshold of 0.1 (faster mutating STRs generally have a larger number of repeats, which are more difficult to measure).

The processing of the BAM by YFull will be no different than what is done by FTDNA. The restriction on what size of STRs can be extracted is the length of the sequencing read. That has not changed. YFull's analysis is a regurgitation of what FTDNA has provided in terms of STRs and variants.

Individuals will not get a "closer" match unless there is a result from a non-FTDNA supplied BAM present in the comparison. You are initially more likely to have a result present in the FTDNA system since the majority of the results originate from that supplier.

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