Michael Cooley's Genetic Genealogy Blog
14 May 2018

A Cooley By Any Other Name

The Cooley DNA Project has identified several early American Cooleys of varying origins, most from the British Isles. Many of these families have grown extensively over the last centuries. Several testers, however, have had no significant Y-DNA matches. Cooley group CF08 is one, having only two testers — father and son. CF06 is another, which also has two testers, cousins of several degrees. Both groups claim descent from the Peter Cooley who immigrated to Virginia with his wife and children as indentured servants in 1774.1 But the first twelve Short Tandem Repeats (STRs) tell us that these groups are not even remotely connected, having a genetic distance of 17 over the 12 markers!

CF0613 24 13 10 16-18 11 12 14 13 11 30
CF0813 23 14 10 11-14 12 12 12 13 13 29

One way or another, the genealogy cannot possibly be correct. Undoubtedly, the children who immigrated with Peter were his own and kits #99728 and #190011 (CF06) are distantly-related cousins. The STR agreement confirms that Samuel Cooley was their Most Recent Common Ancestor. The genealogy going back to him, thus, is proved to be genetically consistent. The descent from Samuel's father, Joseph, can also be verified through testing of a descendant of one his brothers. David, born c1808 and married to Eliza Emerson, has plenty of eligible descendants, for example.

Peter had three sons, the first of whom, Peter Jr, died unmarried and without issue. Only one child, John W, can be attributed to Peter's second son John and his wife Catherine Burner. Although Samuel's descent is confirmed through test results of his two sons, it appears to be impossible to do the same with John's lineage. History, however, has provided a possible answer to this conundrum. The following entries are from the Shenandoah Minute Books.

Mar 12, 1810: John Cooley is to indemnify the Overseers of the Poor for support of a bastard child.

Jan 13, 1812: Jacob Summers is ordered to reimburse Commonwealth for support of a base born child of Catherine Burner.

This doesn't prove that John W was the illegitimate child but the mismatching DNA supports the suggestion. What is needed is supporting evidence — genetic or genealogical — through a collateral line to determine the truth. Unfortunately, it's lacking in both CF06 and CF08. The CF06 Cooleys, for starters, have no STR matches at 67 and 37 markers, and only three near matches at 25 markers, none of which are Cooleys. The E haplogroup, which CF06 has been determined to belong to, is very rare in Europe, but has strong representation in Portugal and Spain. (It has origins in the Middle East and Africa, where it's most seen today.)

CF08 and the Big Y

The son half of the current CF08 membership has tested for the Big Y, a sequencing of more than ten million positions on the Y chromosome. Because FTDNA reports matches only for thirty or fewer differences in SNP values, none are reported for the tester. In other words, there are men who match CF08's terminal SNP, BY4305, but their relationship is so distant that FTDNA doesn't deem it necessary to report them. Indeed, if we are to accept the general notion that a SNP mutation shows up on the Y about every 144 years — or perhaps every three to five generations — working that out over thirty-plus SNPs tells us that the nearest SNP relative in FTDNA's database could go back more than 4,000 years. Indeed, there's no genealogical relevance to be found among those results.

The STR matches for CF08 are just as discouraging. At 67 markers, the nearest match is a genetic distance of 5, a descendant of William Pierce (1755-1843) of South Carolina and Mississippi. That tester, however, hasn't Big Y tested. A descendant of Gustaf Karlsson from Scania, Sweden does have Big Y results. His terminal SNP is S27466, a descendant branch of Z8168 and, therefore, a "sibling" of SNP BY4305, CF08's terminal SNP. This suggests that the branch the CF08 Cooleys belong has a much higher degree of SNP mutations than STR mutations, indicating that the SNPs in this branch happened to mutate a lot faster than the average, the grossly estimated rate of about 144 years.


Not only does FTDNA find no matches for the terminal SNP BY4305, none are found for the four haplogroups upstream of it. Obviously, each has multiple descendants, but they all differ by at least thirty SNPs. Our tester does, however, have one matching BY4305 at YFull, a descendant of Eero Pahlman (1917-1988) of Finland (YFull kit #YF02599). Still, among the nearly 500 STRs extracted from the FTDNA BAM file, none are near matches. All "matching" kits have a genetic distance of dozens — even just shy of 100 — out of the 500 STRs, which — again — amounts to no matches.

Both FTDNA and YFull reports that haplogroup R-BY4305 is comprised of only one SNP — BY4305, a mutation at position 15124289 of the Y chromosome that morphed from the ancestral value of T to a C. This mutation occurred at the birth of a specific man of an unknown location about 2700 years ago (YFull's estimate). YFull's tree for haplogroup R-Z330 illustrates testers with origins all over northern Europe. It's a large and robust branch of the Y-DNA SNP tree. But that doesn't really help us genealogically.

FTDNA reports twenty private SNPs for CF08 — SNPs that are not yet shown to have matches. (Father and son, however, would match one another.) Three of these SNPs may be problematic. A17261, for example, is found in a region called DYZ19, a large disorganized area of repeats (Short Tandem Repeats or STRs). Yseq.net (and other testing companies) advises that any test results for them could be unreliable. (Repeats are somewhat volatile and can insert or delete matching segments over multiple generations). And SNP A17262 is found in a region of the X chromosome that looks much like the Y. Because of the manner in which the labs rip apart the DNA and reassemble it, there can be no certainty whether the sample is, indeed, from the Y or the X. In others word, A17262 may not unique to the Y chromosome.

YFull, on the other hand, has found two additional SNPs not reported by FTDNA: Y106863 and Y110368. CF08, then, is defined by the block of 16 SNPs below BY4305. I'll call it haplogroup R-A17249, named for the first listed SNP.

A17249 A17250 A17251 A17253 A17254 A17255 A17256 A17257 A17258 A17259 A17260 A17263 A17264 A17265 Y106863 Y110368
CF08 Cooleys

If we apply the 144 year per SNP rule to this, we can estimate that the block emerged (one SNP at a time) over a period of about 2,736 years, which is close to YFull's estimate.

What's Next?

If there's a bright spot in the FTDNA results for CF08, it's that the tester is an STR genetic distance of 7 from Dr. Spencer Wells, the founder of the The Genographic Project and a pioneer in the field of genetic genealogy. But a GD of 7 is a big deal. Besides, it's not much of a consolation since there's an absence of genealogical value. What we want is to see this group of sixteen SNPs break up into two or more haplogroups. That could happen should there be a test from another descendant of John's great-great-great grandfather (for example), leaving CF08 with a much smaller terminal haplogroup. In any case, the group has an advantage in that they do come from a well-populated branch, even though their particular twig at present is mightily long and slender. CF06 also has an advantage in that other descendants of Joseph Cooley (1762-) and Margaret Toomey are probably out there. Although it will likely be difficult to attach Peter to the larger picture, it's realistic that a single test will verify the lineage back to him.

In short, we need more testers.

What's in a Name?

So, these two Fredericksburg Cooley families had a definite social tie through Peter's son John but not a genetic one — neither to one another nor to any other known Cooley family, whether in Virginia, Britain or elsewhere. But no matter how certain we might be that John W Cooley arose out of a non-paternal event (NPE) that doesn't make him any less a Cooley. Indeed, we can't yet say whether Peter Cooley's own Cooley heritage ran much deeper. After all, who's to say what a "real" Cooley is?

We know that all names began as descriptors of some kind: the person's location, occupation, physical description, etc. Names often passed with property or with a marriage. Cooley has several known origins: coal field, cow field, Mac Olaf, de Quilly (dating from the Conquest), and the famous Mac Giolla Chúille. In the late eighteenth century the word cooley even meant "broth of boiled meat!" The Oxford English dictionary even gives this example usage from 1543: " If the pacient be weake..ye shall gyve hym the coleys of a yonge capon."

It doesn't really matter when or how a name was acquired, whether from a stepfather or via an inheritance three hundred years earlier. Although surnames and the Y chromosome make for very valuable pairs for the genealogist, at some point the association will inevitably break down. It's at that point that a SNP tree becomes very useful. And we can now trace the CF08 lineage through its SNP tree back tens of thousands of years. As more testing arrives, we'll learn more about the timeline and geographic origins of the markers. We'll likely never find the earliest CF08 (or CF06) progenitor, but we'll be able to follow the trail, the proverbial cookie crumbs, one SNP before the other, through time. We simply need more testers. The ball park is being built. In time they will come.

1 "The following indentured servants bound for four years to go from London to Virginia by the Planter, Mr. David Bowers... Peter Cooley of London, weaver, aged 38; Peter Cooley Jr. of London, weaver, aged 18; John Cooley of London, weaver, aged 16; Joseph Cooley of London, weaver, aged 12." The Complete Book of Emigrants, 1607-1776, Sec V, Ch 25, 1774, p. 44.

2 http://vagenweb.org/shenandoah/bly_1800_1803.htm