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Messages - rt-sails

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To further clarify, the Zacary Taylor who was having children in Lancs in the 1680s could have been a cousin or brother of the man who emigrated to Virginia, apparently ca1660 and not the emigrant himself. The emigrant was James Taylor, who was fathering children until 1696 and died in 1698. 
-rt_/)

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Ancestral Family Tree DNA Testing / Re: Surname Tests - Realistic Expectations
« on: Friday 30 August 13 18:54 BST (UK)  »
Its more than 2 or 3 sentences!
Genetic science is complicated and is composed of multiple complex concepts. I doubt that it CAN be fully explained in two or three sentences with no jargon. (God knows, I've tried!) But, here's another stab at simplifying:
  • The DNA in our cells is inherited from our parents, roughly equally from each.
  • An exception is DNA of the Y chromosome (Y-DNA), which is inherited only by males (it defines maleness) and only from fathers. Y-DNA is relatively stable over many generations and similarity of two haplotypes (i.e., particular patterns) indicates that both sample donors share a direct paternal ancestor. Differences (mutations) between haplotypes yield time-probability windows as to how many generations separate the two donors; in general, the more diffirences, the greater the separation.
  • Mitochondrial DNA (mtDNA) is another exception. It is inherited by both genders, but only from mothers. Present technology does not permit identification of a specific direct maternal lineage from mtDNA.
  • Autosomal DNA (AuDNA) is the DNA in the 23 22 pairs of non-sex chromosomes; it is inherited about equally from each parent, who each got roughly half from each of their parents. However, AuDNA is subject to recombination and "swapping" of DNA segments between each chromosome in a pair, thus complicating analysis and interpretation.  (Oops. One of the 23 pairs is the gender-determining XX or XY; only 22 pairs are autosomal.)
Experts would say the above is an over-simplification; it leaves much out. They'd be right.

I am not trying to be awkward, but everything I have seen about DNA testing just reads like gobblygook to a lay person (and I am not totally thick, do have a basic knowledge of genetics etc), and those who are fans of it can write at great length, but to the run-of-the mill family historian, it just goes over the head.
I cannot see any worthwhile use in it, but seeing as people were saying it has a very legitimate use in genealogy, I was prepared to be openminded and invited someone to tell us exactly how. How does it have a use, how can it be used as a tool?
Using DNA in genealogy requires learning some new concepts, though the skills of analysis and evaluation learned in documentary genealogy will also be helpful. An example may illustrate:
  • Suppose your family history research leads you to two men, both with the same name, born about the same time in the same area. From the available documentation, each is an equally likely candidate.  Which is your ancestor?
  • Y-DNA would be a way to answer the question. Each man would have passed their DNA to their direct filial descendants and comparisons of the haplotypes would (likely) exclude one candidate and point to the other.

For an example using mtDNA, review the investigation showing that the skeletal remains found in Leicester were actually those of Richard III. (He, it turns out, had an uncommon form of mtDNA.)  The investigation relied about equally on documentary genealogy and DNA comparisons. See http://www.theguardian.com/science/2013/feb/04/richard-iii-dna-bones-king.

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Ancestral Family Tree DNA Testing / Re: Surname Tests - Realistic Expectations
« on: Wednesday 28 August 13 20:49 BST (UK)  »
As a genetic genealogist, I resist the term "Surname Tests" and prefer the more specific "Y-STR Tests". Surnames (i.e., inherited family names) are a relatively recent development and are not so fixed and immutable as often believed.

  • Disclosure: I am biased in favor of Y-STR testing. As a surname project administrator, I've seen it help many further their family histories.

The practice of using surnames came to most of Europe after 1000 AD and became universal in England as recently as 1400. Common surnames often have multiple origins (founders);. many who bear the name will not be genetically related to each other within a genealogical time frame.

Another writer mentioned NPE (non-paternal events) which result in a child bearing the name of other than its biological father's birth name. The effects of NPE tend to be cumulative as the name is passed down to succeeding generations. It's estimated that 30% to 40% of people have NPE somewhere in their family trees. Often, the fact of a NPE is found only after a Y-STR test and can present a means of overcoming a genealogical brick wall..

So what are realistic expectations for a Y-STR test?

Chances for matching are certainly improved if one recruits a known descendant of one's direct paternal ancestor to test as well. Only a NPE or wrong genealogy will result in a non-match. The downside is that a match merely confirms what one already knew.

For a "blind test" (potluck) one's matching chances much depend upon the makeup of the database to which your results are compared. A bigger database is better than a smaller one. A database with more people who have a reasonable chance of matching you is better than one with fewer. (For example, Englishmen should probably not test with a company specializing in Chinese DNA.) More inclusive is better than more restrictive.

One's chances also depend on the resolution of the test. A minimal test (12 markers) does not, in most instances, yield enough precision to eliminate ambiguities.

The frequency of your surname is a factor. Rare surnames have a much better chance of matching with the same name than do common names. However, if the name is near extinction, you may not have a close match with anyone living.

Aside: If one has a common, multi-origin name, the Y-STR test can be especially helpful in focusing research on one lineage over others with the same name.

Country of residence is presently another factor. It is true that Americans of English heritage represent only a portion of the English gene pool and that acceptance of this methodology, by comparison, has lagged in England. Participation is growing though and there's no reason why it won't eventually achieve similarly as for Americans of many ethnic backgrounds.

Most DNA surname projects for common names will have about half of participants showing Y-STR matches with surnames other than the one of the project. They can not be grouped into a "Green family" because -- no matter who else they match -- they do not match other Greens.

Expectations may not be met immediately; patience and persistence are recommended. The results have a long shelf-life and may result in matches appearing years later. Often, matches depend on the unknown person who would match you getting tested.

Y-STR testing (or DNA testing of any kind) is not a substitute for traditional, documentary genealogy; it is merely a complement. To expect DNA to come labeled with names, dates, places and other identifiers is to expect more than it can deliver.

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Ancestral Family Tree DNA Testing / Re: Surname Tests - Realistic Expectations
« on: Wednesday 28 August 13 18:59 BST (UK)  »
What I cannot understand about the family tracing bit of DNA research is, if we all originated at/from a single source, we all should be carrying a level/marker of DNA from that source...

The above assumes that evolution of the human species has stopped; it has not. Evolution at the molecular level is a continuing process. Changes in our DNA have occurred since the appearance of homo sapiens sapiens and are still occurring.

While most of our DNA reflects the "single source", some is de novo. Changes happen according to molecular clocks whose ticks can be measured (or estimated) in generations. Careful observation and analysis allow scientists to track emergence of branches of the human family and their ages.

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Ancestral Family Tree DNA Testing / Re: The best test for me
« on: Tuesday 27 August 13 21:31 BST (UK)  »
Thank you for all the advise as for Harrison the full name was William Harrison I did try tracing him but with only a name and the area of Gainsborough I was unable to get anywhere and my second great grandmother married Robert Dixon a few years later in 1893 so the trail goes cold as for the test my aim would be one to see where we originated from and two to see if the test could link me up with anymore relatives much further down my fletcher side but my worry was that the female in the middle would mess that up if that makes sense

In general, the Y-STR results will match with male Fletchers who are direct paternal descendants of your earliest Fletcher ancestor (your 2GGF?). It will also match with Harrisons (if that was your 2GGF's father's name). If that was not his name, it will match with other surnames who also share a direct paternal ancestor.

There are exceptions to the general rule. Certain very common haplotypes will also show "coincidental matches" but one never knows whether one has one of those haplotypes until seeing the results.

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Ancestral Family Tree DNA Testing / Re: The best test for me
« on: Monday 26 August 13 21:38 BST (UK)  »
Hi all I am wanting to go back through my male line of Fletchers ...  I am not sure which test would be best for me as I would imagine the female will throw a spanner in the works any suggestions.
You have a choice of four types of genetic genealogy tests:
1. Y-STR tests "short tandem repeats"("micro-satellites") on the Y chromosome and can identify or exclude a direct paternal lineage within genealogic time. Any intervening female ancestors will break the Y-inheritance chain. Depending on the commonness of the surname, Y-STR is more or less associated with surnames. You may find you have Y-STR matches with men named Harrison, which could suggest that this was the surname of your 2nd great-grandfather's biological father.

2. Y-SNP tests single nucleotide polymorphisms on the Y chromosome and relates to paternal ancestry before genealogic time. Again, the Y chromosome does not pass through a female ancestor.

3. mtDNA is analogous to SNP testing, but for mitochondria instead of the Y chromosome. Mitochondria are passed to both genders, but only by mothers; males do not pass on their mitochondria to their children.

4, AuDNA ("au" meaning autosomal) tests genetic blocks in all chromosomes and can identify similar genetic inheritances up to a limit of about five generations. It is not limited as to ancestors' genders

To trace paternal lineage, I recommend a Y-STR test of at least 37 markers. It can look as far back as 24 generations, roughly about the time of universal surnames. More recent relationships (where both parties share a direct paternal ancestor) will also show as matches.

My opinion is that, at this time, Family Tree DNA is the provider of choice for these tests. Prices are reasonable (as compared to others), reliability and customer service are good, the database (for searching) is large, and support & tools are excellent. I also recommend joining a project for a surname or geographical area in order to obtain further support; this also argues for FTDNA. 

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