Category: England, Wiltshire, Urchfont

A Sainsbury-Ruddle triangulation group

When people descend from a common ancestor and share identical segments of DNA (presumably inherited from that common ancestor), it’s known as a triangulation group.

That’s what we’re looking for in this phase of our genetic genealogy project—to identify the biological grandfather of Richard SAINSBURY of Urchfont and north Somerset (1708-1785). We know from Y-DNA and documentary evidence that his father was John SAINSBURY the younger of Urchfont (1664-1719). But the same sources also tell us that John SAINSBURY the younger was not the biological child of his documented father, John SAINSBURY the elder (1634-1710).

The common ancestors we’re looking for would be at the top of this pyramid. Descendants who inherited identical DNA from those ancestors would be the DNA matches (1, 2, 3, 4) indicated at the base:

What is a triangulation group?

What is a triangulation group?  A triangulation group is a group of people who are all descended from the same common ancestor.  Most often, DNA segments are used to determine triangulation groups.
Source: How to triangulate DNA matches to identify unknown ancestors

So in this phase of the project we’re looking for (a) descendants of John SAINSBURY the younger of Urchfont (1664-1719) who share identical DNA with (b) any documented descendant of an ancestor of John RUDDLE, born in Urchfont, Wiltshire in 1633.

Why John Ruddle?

Why are we looking for DNA matches related to any ancestor of this John RUDDLE of Urchfont?

Because after searching family trees, uncovering genealogical documents, and finding our SAINSBURY line had a “break” in the 1660s, we needed a theory to test. We already had evidence that our SAINSBURY family had a genetic connection to the JARVIS family of Upavon, Wiltshire. So could we find any male in Urchfont in the 1660s with a genetic connection to that JARVIS family?

In fact, there was only one: John RUDDLE of Urchfont. He is, therefore, the leading candidate in our quest to identify John SAINSBURY the younger’s biological father.

To establish a triangulation group to support this theory, the matches we find also need well-documented family trees going back to any ancestor of John RUDDLE Urchfont (1633 -?):

Any ancestor of John RUDDLE (born 1633, Urchfont) could be the source of DNA shared by Somerset Sainsbury descendants if he is, in fact, our ancestor.

If, if, then . . .

If a documented descendant of any ancestor of John RUDDLE of Urchfont shares an identical segment of DNA with at least two descendants of John SAINSBURY the younger’s son, Richard Sainsbury of north Somerset (1708-1785) – and if no other genealogical explanation can be found – then we may have found a triangulation group to prove that the Sainsbury family of north Somerset descends from John RUDDLE of Urchfont, Wiltshire.

Until now, however, we lacked a triangulation group in which one or more descendants of Richard Sainsbury of north Somerset could be shown to share identical segments of DNA with one or more descendants of John RUDDLE’s Urchfont-area ancestors.

But keep in mind, any lack of triangulated matches could also be because the probability that two cousins at this genetic distance will share enough DNA for the relationship to be detected is probably less than 0.002%. (Source:

Which brings us to . . .

The will of Elizabeth Jarvis (d. 1602)

One hundred and fifty years before Richard Sainsbury appeared in the Bristol area of Somerset, Elizabeth Jarvis of Upavon, Wiltshire, wrote her last will and testament.

Elizabeth had been a widow for 17 years – ever since the 1585 death of her husband, John Jarvis, haberdasher of Upavon.

As an Elizabethan haberdasher, John would have sold an assortment of small goods:

buttons, pins and fastening hooks, thimbles, silk threads and trimmings and laces of all kinds as well as felt hats and caps, gloves of all sorts, hosiery, purses of taffeta and leather and red satin pin cushions . . . playing cards, spectacles, combs, crystal glasses, ordinary drinking glasses, wooden plates, knives and even pictures.

Source: T. Cooper. (2003). What was it like to go shopping in Elizabethan London?

In effect, John Jarvis ran the Elizabethan equivalent of a Dollarama or Poundland.

In her will, written 17 years after he husband’s death, Elizabeth Jarvis bequeathed the residue of her estate to three of her children: John, Mary, and Dorothy. She also named her son-in-law (and Dorothy’s husband) John Sainsbury of Urchfont:

Elizabeth Jarvis identified her daughter “Dorithie” (third line from the bottom) and son-in-law John “Saintesberie” (1555-1634) in her 1602 will. Source: Wiltshire and Swindon History Centre. Reference Number: P2/IJ/38

John Sainsbury and Dorothy Jarvis, who married in Urchfont in 1587, were the grandparents of John RUDDLE of Urchfont through John’s mother, Edith SAINSBURY (c.1608-1670).

Any DNA shared by descendants of Dorothy’s parents, John and Elizabeth Jarvis, if also shared by two or more Somerset Sainsbury descendants, would form a triangulation group of enormous significance for this project’s latest goal: to identify the paternal grandfather of Richard Sainsbury of north Somerset.

Absent any other genealogical or genetic explanation, a triangulation group made up of descendants of John and Elizabeth Jarvis of 16th-century Upavon, Wiltshire and any descendants of Richard Sainsbury of 18th-century Somerset would support the theory that our ancestor, Richard Sainsbury, was the grandson of John RUDDLE (1633-?).

And, in fact, that’s exactly what we’ve found.

Triangulation Group #1

Using GEDmatch and MyHeritage, we identified two Somerset Sainsbury cousins in Canada who share an identical segment of DNA with two documented descendants of John and Elizabeth Jarvis of Upavon.

The blue section of this view of chromosome 15 shows the area of significant validity shared by members of this triangulation group.

One member of this group lives in New Zealand (Kia Ora, NR, for your help with this research!) the other lives in the United States.

Both have well-documented family trees going back to John and Elizabeth Jarvis of Upavon. No other family lines appeared to explain their genetic and genealogical relationship, which is indicated in this downloadable family tree:

Four other were identified who share the same segment of DNA but their family trees could not be traced back to a common ancestor. (One ended in colonial America, three ended in Warwickshire and/or Staffordshire.)

Our first good evidence

It’s clear from their family trees that NR and DS very likely (in fact, almost certainly) inherited this segment of DNA from their most recent common ancestors, John and Elizabeth Jarvis of Upavon.

And a very reasonable way to explain the presence of the same segment of DNA in two Somerset Sainsbury descendants is that their ancestor, Richard Sainsbury of Urchfont and north Somerset, was the grandson of John RUDDLE of Urchfont – himself the great-grandson of John and Elizabeth Jarvis of Upavon.

The first of many?

Over the course of this project we’ve identified almost 100 genetic matches among Somerset Sainsbury descendants to descendants of Richard Sainsbury’s Urchfont-area ancestors. We also have Y-DNA evidence that shows his own father, John SAINSBURY the younger (1664-1720) was not, in fact, the biological child of John SAINSBURY the elder (1634-1710). (Y-DNA results confirm Urchfont origins of north Somerset Sainsburys.)

This is the first triangulation group to support the theory of our RUDDLE origins. And if it’s valid, there should be others waiting to be discovered.

Disclaimer: As with any research project, when new evidence comes to light, former theories may change. This blog post includes theories and conclusions developed from the best available evidence at the time this post was written. It may be corroborated or refuted by later research. This post must therefore be considered in the context of all information presented in earlier and later posts.