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gcoombsjr
06-18-2018, 06:27 PM
I just got LivingDNA results for autosomal, mtDNA, and y-DNA and I am a bit lost as to where to go with the information beyond the overviews that the company provides about the two haplogroups (T2b3 for the motherline and R-Z284 for the fatherline.) Can anyone suggest some good introductory resources for a beginner to start to make sense of the various strings of numbers provided? Any pointers would be appreciated.

GC

C J Wyatt III
06-18-2018, 07:28 PM
What are you looking for?

RobertCasey
06-18-2018, 07:51 PM
As C J points, you really need to formulate and state your goals for testing. But there are three major kinds of testing:

1) autosomal testing - whose prime genealogical goal is to find matches. But this takes a lot of analysis to determine which line each matching segment belongs to. Plus many people place several atDNA tests of close relatives to start this sorting out process. The big advantage of this test is if you have very recent brick walls (post 1850). The downside, after only four or five generations some branches of your pedigree are at noise level where you start losing the ability to match older lines. So, if you have all your lines already traced back to the 1700s, atDNA morphs into query tool vs. breaking down brick walls. The minimal mtDNA test from LivingDNA, Ancesty.com and 23andme are extremely limited mtDNA tests and are very dated.

2) mtDNA testing. Save your funds. This test has minimal genealogical value. The problem with this test is - poor sample size. The mtDNA strand is only 16,000 base pairs long - not much for significant content. Big Y reveals around 10,000,000 base pairs and the YElite2.1 long read reveals around 20,000,000 base pairs. So the potential of YDNA to make connections has 1,000X better chance than mtDNA.

3) The YDNA testing has the best long term potential of all tests. Your mileage will vary based on: 1) how prolific your haplogroup is compared to others (1,500 to 2,500 years ago); 2) how well tested and analyzed your part of the haplotree is; 3) the geographic region associated with your male line (UK/Ireland has the most testing due Americans and other former British colonies are trying to find that elusive connection back to the homeland and more disposable income that builds larger databases). France and Germany are way behind UK/Ireland but have a pretty good database. Balkan countries (Bulgaria, Hungary, Romania, etc.) have limited amount of testing to date. So set your expectations based on your YDNA line's geographic origins. Again, the YDNA testing that is bundled with atDNA tests is extremely limited and very dated. LivingDNA just copied the competition and added a minimal amount more. Pick one male of most interest and concentrate on that line only until you get how YDNA works. Always start with Y67 markers from FTDNA - prior to any YSNP testing. You may luck out and immediately get assigned a prolific well known haplogroup up front which would minimize your YSNP testing costs as you may be able to go directly to a recent SNP pack test or go directly to Big Y500 and be done with nickel and dimes lost to lower functional YSNP testing.

msmarjoribanks
06-18-2018, 11:08 PM
The value of mtDNA for genealogy is limited. It can confirm some research (my dad's test helped confirm my research on his farthest back line, but only because of the excellent pool of matches at FTDNA). It can also help suggest paths/rule out matches if they are supposed to be along that particular line.

Mostly, though, it's just a matter of idle interest, which is what it was for me originally.

What we know from mtDNA is currently limited, because it mutates SO slowly that the main haplogroups (for Europe, U, H, and a variety of others, including K (mine) and T (yours), tend to be found in a huge variety of places, at least in some level, so it's not useful in identifying where a line originated (Y-DNA can, but doesn't always, give you more about that). As they test more samples and population samplings more specifically and as more people are tested, I think we will find out more and it will get more helpful.

Re: T2b3, here is some information (from Eupedia's write-up):

"Haplogroup T is composed of two main branches T1 and T2. The two of them have very different distributions, which are diametrically opposed in most regions....

Haplogroup T2 peaks among the Udmurts (24%) and the Chechen-Ingush of Daghestan (12.5%). After that T2 is most frequently encountered in the Netherlands (12%), Sardinia (10%), Iceland (10%), Switzerland (9.5%), Hungary (8.5%) and Ukraine (8.5%), as well as among many ethnic groups around the Caucasus such as the Kumyks (10%), Azeri (9.5%) and Georgians (9%)....

The mutation defining haplogroup T happened some time around 29,000 years ago, probably in the East Mediterranean region. T1 and T2 split from each others some 21,000 years ago, toward the end of the Last Glacial Maximum (c. 26,500 to 19,000 years before present). T2c and T2d developed almost immediately afterwards, followed by T1a, T1b, T2a and T2f circa 17,000 years ago, and T2h 15,000 years ago. The most recent subclades are T2b, T2e and T2g, which date from 10,000 years before present, during the Pre-Pottery Neolithic period."

My note: so you would be no more than 10,000 years separated from your common ancestor for other T2b's, but obviously that's a LONG time, and explains why it's going to be so spread out, as people moved around a lot during that period of time. Anyway, back to Eupedia:

"T2b was by far the most successful, accounting for roughly half of all T2 individuals in Europe. T2b is subdivided in 30 basal subclades (+ their own ramifications) to date, twice more than all other T2 subclades combined."

Apparently, T2b3 is "found in mostly in western Europe (especially Sardinia), but also in eastern Europe, Azerbaijan and the Maghreb"

There's more here: https://www.eupedia.com/europe/Haplogroup_T_mtDNA.shtml

gcoombsjr
06-19-2018, 01:52 AM
Thanks for the replies. What I am hoping for is a pointer to a good tutorial, book, etc that will explain what I am looking at when I review the results I received. For example, when I look at the list of codes from the y-dna genetic signature and see that 73 of them map to BT and 35 of them map to CT, what does that mean? Out of 316, 80 don't map to anything on the lists. The mtDNA results are less intimidating with only 19 codes that are relatively easy to match up to nodes in the haplotree.