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Mark D
11-21-2013, 01:02 AM
Although I assume most everyone here gets emails from the DF27 Yahoo Forum, in case not, I noticed that CeCE Moore in her blog posted a SNP comparison chart provided by Britains DNA:

http://www.yourgeneticgenealogist.com/2013/11/a-list-of-alternate-snp-names-for.html

Mark

razyn
11-21-2013, 05:32 AM
Couldn't help noticing that Jim Wilson says S250 (i.e. DF27) is unfortunately one of those SNPs "Illumina appear to have removed... from the design."

I think that's the same problem FTDNA had when designing the Geno2 chip; it's a palindromic marker or something, and has to be scanned twice to know whether the call is + or - (hence the "nested primers" approach when it was Sanger sequenced, which meant that specific test had to be run twice, and therefore cost more).

I'm vague about the actual science, but these things were discussed a little when the DF27 test became available a bit over a year ago.

Mark D
01-05-2014, 04:14 PM
Couldn't help noticing that Jim Wilson says S250 (i.e. DF27) is unfortunately one of those SNPs "Illumina appear to have removed... from the design."

I think that's the same problem FTDNA had when designing the Geno2 chip; it's a palindromic marker or something, and has to be scanned twice to know whether the call is + or - (hence the "nested primers" approach when it was Sanger sequenced, which meant that specific test had to be run twice, and therefore cost more).

I'm vague about the actual science, but these things were discussed a little when the DF27 test became available a bit over a year ago.

Is that why FTDNA doesn't report DF27, because they don't test it? I would think the DF27 project would have more members if FTDNA didn't skip over it on the results page.

razyn
01-06-2014, 12:57 AM
I think it's more a matter of their haplotree's not having been updated since the end of 2010. DF27 was discovered in the fall of 2011, so it's invisible -- as are a few hundred other recent discoveries, both on and off the ISOGG tree for their respective groups.

GoldenHind
01-06-2014, 01:07 AM
Is that why FTDNA doesn't report DF27, because they don't test it? I would think the DF27 project would have more members if FTDNA didn't skip over it on the results page.

Perhaps you're referring to Geno 2 results? They did not include DF27 in that test. So obviously Geno 2 results, when posted on FTDNA make no mention of DF27.

FTDNA most certainly does test for DF27, though it has to be ordered individually, and that company is responsible for nearly all of the DF27 that has been identified.

Mehrdad
01-06-2014, 02:11 AM
So what's the difference between this test, the Big Y from ftDNA?

Heber
01-06-2014, 10:52 AM
I understand that the recent Genographic project in Asturias found mainly R1b-DF27 in the same way as the Mayo project found mainly R1b-L21 and specifically M222. Apparently up to 32 new SNPs were found under M222. Hopefully we will reap a similar harvest under DF27. I don't know if they used the Geno 2.0 chip or a prototype 3.0 NGS chip. They have not yet published a technical paper. I analysed my Geno 2.0 results using the Morley draft tree and got the following results. It would be interesting to do something similar for a Geno 2.0 DF27 result.

http://www.pinterest.com/gerardcorcoran/genographic/

Heber
01-06-2014, 10:53 AM
http://www.pinterest.com/pin/32721534766773137/

Mark D
01-06-2014, 02:43 PM
Perhaps you're referring to Geno 2 results? They did not include DF27 in that test. So obviously Geno 2 results, when posted on FTDNA make no mention of DF27.

FTDNA most certainly does test for DF27, though it has to be ordered individually, and that company is responsible for nearly all of the DF27 that has been identified.

Thanks for both your and razyn's responses. ie., FTDNA tests DF27 individually but does not show it on their haplotree. I had joined the DF27 project assuming that as I was L176.2+ I was clearly DF27+, without having specifically tested for it. I also see that Geno 2.0 does not show any DF nor S results, and I look forward to my Big Y results showing hundreds more SNPs and FTDNA updating their tree. I understand this is a massive work in progress and do appreciate everyone's assistance in this.

I hope one day the powers that be in this field can sort out the nomenclature of SNPs so that we non-professional consumers of DNA testing products can understand more clearly what it all means.

GoldenHind
01-06-2014, 06:59 PM
I understand that the recent Genographic project in Asturias found mainly R1b-DF27 in the same way as the Mayo project found mainly R1b-L21 and specifically M222. Apparently up to 32 new SNPs were found under M222. Hopefully we will reap a similar harvest under DF27. I don't know if they used the Geno 2.0 chip or a prototype 3.0 NGS chip. They have not yet published a technical paper. I analysed my Geno 2.0 results using the Morley draft tree and got the following results. It would be interesting to do something similar for a Geno 2.0 DF27 result.

http://www.pinterest.com/gerardcorcoran/genographic/

If they tested for DF27, they did not use the Geno 2.0 chip.

GoldenHind
01-06-2014, 07:09 PM
Thanks for both your and razyn's responses. ie., FTDNA tests DF27 individually but does not show it on their haplotree. I had joined the DF27 project assuming that as I was L176.2+ I was clearly DF27+, without having specifically tested for it. I also see that Geno 2.0 does not show any DF nor S results, and I look forward to my Big Y results showing hundreds more SNPs and FTDNA updating their tree. I understand this is a massive work in progress and do appreciate everyone's assistance in this.

I hope one day the powers that be in this field can sort out the nomenclature of SNPs so that we non-professional consumers of DNA testing products can understand more clearly what it all means.

Your assumption was correct. L176.2 is a subclade of Z196, and Z196 is a subclade of DF27. Anyone who has tested positive for a DF27 subclade (which also includes SRY2627 among others) is necessarily positive for DF27. It is however entirely possible to be negative for all the currently known DF27 subclades and still be DF27+, in which case one is designated DF27*.

FTDNA's R1b haplogroup tree has been outdated for many years. It is so out of date that it can be misleading, and it has caused endless confusion for many of their customers.

They say they are finally in the process of updating it. It must be a technical nightmare to update the haplogroup subclade designation of all their R1B customers.