Michael Cooley's Genetic Genealogy Blog GEN • GEN
11 May 2016

The Bogus “Dutch Cooley” Lineage

Thanks to a 1930s genealogy written by one-time poet, Lura Coolley Hamil, a number of Cooley families have been misidentified. I'm not going to enumerate here all the many errors Hamil committed to paper — except to say that she spent only six months on the project. I've spent ten years looking at the genetic evidence. Furthermore, there is no paper evidence to support her claims.

The following series of slides utilizes Y-STR data. To refresh memories, STRs (Short Tandem Repeats) are strings of bases, the A's, C's, T's, and G's of the genetic alphabet soup, that repeat at specific locations on the Y chromosome n number of times. For example, at position DYS385b (the sixth column, below) I have 13 repeats of GAAA. Normally, at least 37 positions (markers) are examined to determine the likelihood that two people are related. But only 12 are needed to disprove a relationship. For 12 markers, at least 11 should match.

The first frame is taken from Hamil's tree. Those highlighted in blue in the second frame are persons for whom at least one descendant has tested. The yellow boxes in the inner graphic, found in the later frames, indicate mismatches. As we see, none of these six families are even remotely related along the paternal line, proving that Hamil's claims were false. As Elizabeth Cooley, a one-time genealogist of the Cooley Family Association of America, wrote in 1977, Hamil's work "should be labeled with a huge 'Skull and cross bones.' Mrs. Hamil went about grabbing up anything she felt might go together, has mixed up many different Cooley families, etc." The following proves the point.

I believe I've identified a seventh lineage but have not yet located a potential tester.