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The DNA lines get more tangled…

No, DNA doesn’t lie.

But it sure can confuse the issue.

Case in point: The Legal Genealogist‘s Robertson great grandfather and his line.

Jasper Carlton Robertson was born in April 1871 in Texas,1 the youngest of the 11 known children of Gustavus Boone and Isabella (Gentry) Robertson. The Robertsons came to Texas just after the Civil War from their home state of Mississippi.2

We can trace the line back to Gustavus’ father easily — William M. Robertson is recorded living with his son’s family on both the 1850 and 1860 censuses.3 And with some effort we have identified Gustavus’ mother’s line, placing William in Lowndes County, Mississippi, at the time of his marriage to Delilah Moore.4

Judging from those census records, William M. Robertson was born in North Carolina. But that’s as much as we know about his roots. There’s not one clue about his parents or where in North Carolina he might have come from.

Which, of course, makes YDNA testing a good choice to try to extend the research. YDNA, remember, is the kind of DNA that only men have and that is passed from father to son to son down through the generations largely unchanged.5

Fortunately, my great grandfather Jasper had sons as well as the daughter, Opal, who became my grandmother. And one of those sons had sons. And one of those sons — my mother’s cousin Michael — agreed to take a YDNA test. His was, in fact, one of the very first DNA tests I paid for.

And — sigh — it turns out that our Robertsons aren’t exactly what we were expecting. We figured Scots-Irish — and that may still be true — but our YDNA haplogroup is J-M172:

Haplogroup J-M172 is found in the highest concentrations in the Caucasus and the Fertile Crescent/Iraq and is found throughout the Mediterranean (including the Italian, Balkan, Anatolian and Iberian peninsulas and North Africa).

The highest ever reported concentration of J-M172 was 72% in Northeastern Georgia. Other high reports include Ingush 32%, Cypriots 30-37% , Lebanese 30%, Assyrian, Mandean and Arab Iraqis 29.7%, Syrians and Syriacs 22.5%, Kurds 24%-28%, Pashtuns 20-30%, Iranians 23%, Ashkenazi Jews 24%, Palestinian Arabs 16.8%-25%, Sephardic Jews 29% and North Indian Shia Muslim 18%, Chechens 26%, Balkars 24%, Yaghnobis 32%, Armenians 21-24%, and Azerbaijanis 24%-48%.6

Now this makes perfect sense for our Scots-Irish family origin story if you imagine a Roman legionnaire romancing a Scots girl centuries ago along Hadrian’s Wall. But that theory doesn’t help figure out who William’s parents were.

So we look at our matches. Michael has 14 matches at 37 markers: one at a genetic distance of 0; seven at a genetic distance of 2; five at a genetic distance of 3; and one at a genetic distance of 4. Of the 14, 11 have a surname approximating ours: seven Robinsons; two Robersons; one Robison; and one Robertson.

The Robertson — of course — is among the ones who are least closely related. The one most closely related is — of course — an adoptee with no information about his parents.

Seven of his matches haven’t tested beyond 37 markers, so at 67 markers, Michael has eight matches: the adoptee at a genetic distance of 1; two Robinsons at a genetic distance of 3; a Roberson and that one Robertson at a genetic distance of 4; a Robinson at a genetic distance of 5; and two others with entirely different surnames at genetic distances of 5 and 7 respectively.

Four of those matches haven’t tested beyond 67 markers, so at 111 markers, Michael is down to three matches: the adoptee at a genetic distance of 1; one Robinson at a genetic distance of 4; and the Robertson at a genetic distance of 6.

Two of these — the adoptee and the Robinson — have also taken an autosomal DNA test: the test we use to look at the DNA we receive from both parents and that can help identify cousins within five or six generations.7

The Robinson is not on Michael’s autosomal match list.

But the adoptee is.

Okay, so maybe we won’t find William’s family but maybe we can help the adoptee find his.

And looking at the which-side-of-the-family icons, the adoptee is going to be on Michael’s father’s side of the family, and I’m all ready to look at that father’s father’s father’s side.

Except that the matches in common tell a different story.

Take a look at that chart up above. The ones in red are the most recent common ancestors of the closest matches in common.

And they don’t come from Michael’s father’s father’s father’s side.

The closest matches in common are all from his father’s mother’s mother’s mother’s side.


Take a DNA test, they said.

It’ll help you figure things out, they said.

Unless, like mine, the strands of your family tree end up looking like a plate of spaghetti.

The DNA lines are all tangled up.

Back to the drawing board.

Cite/link to this post: Judy G. Russell, “Revisiting the Robertsons,” The Legal Genealogist ( : posted 27 June 2021).


  1. See Oklahoma State Board of Health, death certificate 3065 (1912), Jasper C. Robertson; Bureau of Vital Statistics, Oklahoma City.
  2. See See “Mrs. Isabella Robertson,” Cooper (Texas) Review, 16 October 1908, p. 9, col. 2; digital images, University of North Texas Libraries, The Portal to Texas History ( : accessed 4 Feb 2021).
  3. 1850 U.S. census, Winston County, Mississippi, population schedule, p. 373(A) (stamped), dwelling 809, family 816, William M. “Robinson”; digital image, ( : accessed 27 June 2021); citing National Archive microfilm publication M432, roll 382. Also, 1860 U.S. census, Attala County, Mississippi, Township 14, Range 8, population schedule, p. 76 (penned), dwelling 455, family 494, Wm. M. Robertson; digital image, ( : accessed 27 June 2021); citing National Archive microfilm publication M653, roll 577.
  4. See Judy G. Russell, “Landing the fourths,” The Legal Genealogist, posted 22 Dec 2020 ( : accessed 27 June 2021).
  5. ISOGG Wiki (, “Y chromosome DNA tests,” rev. 30 Oct 2020.
  6. Wikipedia (, “Haplogroup J-M172,” rev. 4 June 2021 (internal citations omitted).
  7. See ISOGG Wiki (, “Autosomal DNA,” rev. 21 Oct 2020.
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