A report by Arthur T. Corey
27 January 2003

Dr. Arthur Thomas CoreyA project was undertaken by the Cory Family Society to determine the genetic relationships between Cory/Corey family lines in North America and Britain by analyzing Y-chromosome markers. We wished to learn whether or not the progenitors: William of Portsmouth, John of Long Island, and Thomas of Chelmsford were genetically related. Each had arrived in America during the period 1635-1645. We also wished to learn where in Britain the progenitors lived before arriving in America, and to what current Cory lines in Britain they might be related.

Why DNA is useful for genealogical research

Two kinds of DNA material are useful for genealogical studies: Mitochondria and Y-chromosome bodies found in cells of living organisms. Mitochondria bodies found in all human cells are handed down from mother to her children virtually unchanged. Although not directly involved with reproduction, mitochondria contribute to some human characteristics and are associated with energy conversion in cells. Chromosome DNA is directly involved in reproduction and DNA bodies on chromosomes control most human characteristics. Y-chromosomes are found in the nucleus of cells of males only, paired with an X-chromosome. The nucleuses of female cells contain pairs of X-chromosomes only, and only males can contribute DNA from Y-chromosomes to their male offspring.

Both types of DNA have been used successfully to answer genealogical questions, including the genealogy of some well-known people in highly publicized cases. However, Y-chromosome DNA is more useful for tracing the ancestry of individuals bearing a particular surname. Most women in western cultures have historically taken the surname of their husband upon marriage. Bodies on the Y-chromosome are handed down virtually unchanged from father to son for generations, except for rare mutations. This property makes the Y-chromosomes an ideal focus for genealogical studies because, barring adoption or illegitimacy, the Y-markers parallel the surname.

By determining the Y-markers of males bearing the same or similar surname, it is possible to determine (with a high degree of confidence) whether or not individuals have a common paternal ancestor. It is also possible to guess the number of generations two individuals are removed from their Most Recent Common Ancestor (MRCA) from the number of mutations found. Unfortunately, it is difficult to pinpoint the exact ancestor using genetic techniques currently available.

Each specific location on a chromosome has its own mutation rate, but to date the specific rates are unknown. Currently, the laboratory that did our analyses estimates that a total of about one mutation occurs (at one of the 26 locations the laboratory examines) in ten generations. However, this estimate is likely to change as the laboratories conducting the analyses obtain more data. It has already changed from one every 5 generations to one every 10 generations since we started our project.

The percent confidence for the estimated MRCA is currently not reported. If more than three mutations have occurred, the laboratory will report that the individuals are ?genetically unrelated.? They mean by this that any common ancestor is probably sufficiently removed that the genetic relationship is insignificant.

The publicity resulting from a dispute involving the claims of black descendants of Thomas Jefferson (and its solution) has resulted in much research to develop Y-chromosome analysis as a genealogical tool. For example, Brigham Young University has an ambitious research project led by Dr. Woodward. The program is supported by the Molecular Genealogy Foundation. A benefactor of the foundation, Jim Sorenson, established a laboratory in Salt Lake City to provide Y-chromosome analyses for the public. It was this laboratory (Relative Genetics) that I contacted to see if they could help our Society establish the relationship, if any, between the three main Cory/Corey progenitors in America.

The Cory Family Society DNA project

Charlotte Muller, our late Society Historian, was selecting the participants for the first phase of a Cory Family Society project involving American participants, and was planning to obtain English participants for a second phase at the time of her passing. At the last annual meeting of our Society in Seekonk, Massachusetts, Margaret Bruegel presented a check to our Society for $ 5000.00 to defray the cost of completing our DNA project. The donation was a gift from the family of Charlotte Muller to honor their mother who, along with several other members, had suggested the project a couple of years earlier. . We were able to expedite the second phase by using some of her family's gift to defray the cost of analyses of DNA samples from English participants.

The objective of the first phase was to determine whether or not the three main Cory family lines, mentioned in the introduction, are genetically related. The objective of the second phase was to explore the relationship between current English Cory lines and to determine how the American and English lines may be related.

Analyses have now been performed by Relative Genetics on a total of 14 participants, six from England and eight from America. One of the American participants, from a family of relatively recent immigrants, was selected by the English Society as a representative of one of their family lines. Relative Genetics has now provided a report giving the results of the analyses performed to date. A summary of their report follows.


Charlotte Muller, contacted a number of Cory/Corey males who agreed to furnish DNA samples for Y-chromosome analysis. She selected Cory males with well-documented records of descent from one or the other of the three progenitors mentioned. Those selected by Charlotte included: our web master, Earl Cory, from the Thomas line; John H. Corey of Rhode Island and Thomas Corey of Nebraska from the William line; and Charles Cory of Virginia from the John line. It is likely that Charlotte contacted others before her passing, but I was not able to determine who they were.

Our president, Fred Corey, volunteered to furnish a sample as a representative of the William line. I included my own sample because my brother and I wished to establish our own ancestry beyond our great grandfather. Alan Cory from Colorado was included to provide a second well-documented representative from the John line. Following the 2002 meeting in Seekonk, Arthur E. Corey from Connecticut requested that he be included as a participant.

After the lab had completed their analyses of the first seven American participants, we asked the Cory Family Society of Britain to suggest English participants. They appointed Jean Hayes to coordinate the selection of participants, with well-documented pedigrees, representing Cory family lines in Britain. Jean selected five English male participants representing family lines in Britain. She also requested that her relative, Halsey D. Cory from Florida, be included to represent her own family line.

Those selected by Jean Hayes, and the family lines represented, included:
Michael R. Cory (Norfolk), Dr. William Cory (Kent/Northampton), Colin Cory (Northampton), John P.F. Cory (Poundstock), Dennis John Cory (W. Putford), Halsey D. Cory (Pyworthy), and Don Reginald Cory (Australian/Holsworthy).


DNA analyses indicate that the three Cory progenitors identified did not have a common ancestor within the number of generations regarded as genetically significant. Thomas of Chelmsford was not related to either William or John. John and William were definitely not father and son, at least not biological father and son. This was a major surprise for many of our Society members, as well as researchers in Britain, because there was convincing circumstantial evidence indicating that Thomas of Long Island was the father of William. The circumstantial evidence leading to this conclusion was reported in the Cory Family Society newsletter of September 1999.

Charles and Alan Cory were found to be related, verifying their documentary records of descent from John of Long Island. Their Y-chromosomes differed at only one of the 26 sites examined. John H. and Thomas Corey are also related, verifying their documentary evidence of descent from William of Portsmouth. Fred Corey is probably related to William of Portsmouth also, but his Y-chromosome differed from those of John H. and Thomas at three sites, indicating a more distant relationship, or possibly no relationship. Earl Cory, Arthur T, and Arthur E. Corey have Y-chromosomes that differ at only one site. Since Earl's descent from Thomas of Chelmsford is well documented, it is likely that Arthur T. and Arthur E., as well as Earl Cory, are from the Thomas line. At least, they share a common ancestor with Thomas.

Only two of the English participants appear to be genetically related. Dr. William Cory and Colin Cory from the Northampton line are both related to Thomas of Chelmsford. The Y- chromosome of Colin is identical to that of Arthur T. Corey from Colorado at all 26 sites examined, and differed from the other participants from this line at only one site. The other English participants appear to be unrelated to one another, or to any of the three main American lines.

Unfortunately, the English coordinator failed to identify a participant from the Bristol area where William of Portsmouth was born. I have asked her to include a Bristol participant in the future if one can be found. In any case, we now have documentary evidence that William came from Bristol, and DNA evidence that Thomas of Chelmsford was from the Northampton line. We have yet to identify the family line for John of Long Island, but we hope to determine his line from DNA analyses of additional participants. In any case, DNA evidence indicates that the Long Island line is not related to the Norfolk line that includes the Bramerton Cory family.

How you may participate

Many of you, who like me have insufficient documentation to be confident of what Cory/Corey line in America you are descended from, may wish to participate in our project. If you are a male bearing the Cory/Corey surname or have a male relative with that surname, you can discover which line you are from, provided your relative will volunteer to participate. The cost currently is $175 per participant, provided the analysis is done as part of our group project.

You may participate in our project by sending the name and postal address of your Cory/Corey donor, and a check to cover the laboratory charge. Please include your e-mail address, as this will greatly facilitate communication. By sending your name and address you will be agreeing to have the results of the analysis made available to the membership of the Cory Family Society by means of our newsletter. Send inquires to:

Thomas E. Corey
DNA Project Coordinator

110 N. Cherokee Road
McCook, NE 69001-2275

Addresses will be sent to Relative Genetics. Relative Genetics will then send a sample kit to each donor including a ?Buccal Swab? along with directions for obtaining the sample from inside the cheek. A device for collecting and mailing the sample back to Relative genetics will be included. Relative Genetics will perform the analyses when they receive a check covering the laboratory charge. After the laboratory completes the analyses, a report will be sent to me that will be forwarded to each participant along with my own summary of the results.

A check covering the laboratory charge should be made out to Relative Genetics and its purpose (for a DNA analysis) should be indicated on the check. You should indicate that you are a participant in the Cory Family DNA project. The Postal address of Relative Genetics is:

Relative Genetics
2495 South West Temple
Salt Lake City, Utah 84115

We hope that many of you will participate in our project. The more participants involved the more information we will have about the history of Cory/Corey family lines. The charge of $175/participant is a small sum compared to the cost of obtaining comparable information by other means. Discovering your Cory family line early will greatly narrow the scope of research needed to fill out your family tree.

If you have additional questions concerning Y-chromosome analysis, you may address them to Diahan L. Southard, Bioanalyst for the laboratory. Her e-mail address is: diahan@relativegenetics.com, and her phone number is (801) 461-9769.