Bath, Bathe, de Bathe Families DNA Study

DNA Study

of the


Bathe and de Bathe,


of English and Irish Origins.



Please read the following carefully, before deciding to participate.


                 Project Status 19/02/2006               

               We have recently been able to document and provide over 400 years of history and lineage for an Australian Bath family, who joined our project through the participation of one of its male members.
                Though calculations to establish the MRCA (most recent common ancestor) would have suggested a much earlier time period, in ancient history in fact, the MRCA was found only some 10 generations ago. This suggests that having the same surname and a close test result may indicate a nearer relationship than the current fomulas might lead one to believe.
                 Of course, we cannot promise the same outcome for all participants, but persons contemplating their participation should consider the possibility against what it would cost, in time and money, to have performed the research themselves.

                                                                         Martin Bath
                                                                     Project Administrator


Project Outline

             It is recognized that tracing one's genealogy back multiple generations is a time consuming, expensive process that often leads to roadblocks and dead ends. Birth, marriage and death certificates only began in England in 1536 and for many generations were haphazard at best. Whenever found Irish records were destroyed by Protestant extremists and later records were burned during the Dublin uprising in 1922. Devon, likewise, lost its archives during the German bombing of Exeter. Added to this, people did not leave forwarding addresses when they moved from place to place, necessitating far flung searches in the often futile hope of picking up their trail again. This study is intended to eventually become a resource for Bath / Bathe family genealogists, by giving them an indication of to which of the subject branches they are most closely linked and therefore an indicator of where and during what timeframe they may possibly find a connection.

         As stated in the body of this web site there are two opposing theories as to the origin of the English/Irish surnames of Bath, Bathe and de Bathe. The first is the commonly held surmise that all families of that name have their origin in the medieval town of Bath, Somerset and that these multiple families adopted that town's name independently of one another. The second is that most, if not all, of these families are descended from the prosperous, medieval family of de Bathe / Bathonia / Baa, whose surname is argued to be derived from lands of that same name in Devon. The secondary purpose of this DNA study is to obtain an indication as to which of these theories is the more probable. Admittedly, the chances of succeeding in this respect are quite remote, given that over the thirty four generations there may have been multiple adoptions, "straying" wives etc..           

          This project began on November 17, 2005. Whether or not it meets the above stated objectives will depend entirely on the number of participants it attracts.

Participant Criteria

         1)  As we are testing the Y-chromosome you must be a male. Females can participate only by obtaining a sample of a near male relative i.e. brother, father.

       2) Your surname must be Bath, Bathe or de Bathe. No matter the spelling it must be pronounced "Bath". Families with the surname Bathe who pronounce it as "Baithe" are not connected to the subject families. (see criteria 3)

      3) You should be fairly sure that your family originates in England, Ireland, or perhaps Wales. Many English Bath / Bathe families migrated to Wales during the 19th century. 

          Families with the name Bathe / Baethe / Baithe / Beith etc. and who pronounce the name as "Baithe", originate from the Scottish town of Beith, Ayrshire and are not of interest to this study.  

          Persons of the family name of Bath, living primarily in the United States and Canada, should be aware that some Russian, German, French and even East Indian names were "anglicized" to this form when their ancestors migrated to those countries. However, in most cases, ancestral first names often reveal the country of origin. 

           Batho, Bathgate and other similar surnames containing the name "Bath" are unlikely to find a connection in this study. Similarily, a theory exists that some Bath surnames are Cornish in origin and may have a connection to the Bagh or Bache surnames. We'd suggest that any holders of these names, who are interested in a possible connection, set up their own DNA study and compare their results to ours. 

     4) You must be willing to provide a sample, pay the required fee(s) and share the DNA results with others. No personal information on any of the subjects will ever be published on the internet, or other medium. Should another participant wish to contact you your contact information will only be divulged after you have given your written permission.

The Cost

      The initial test of 12 markers currently costs $ 99.00 US with a $4.00 US shipping charge. This is the laboratory processing fee and not ours.

       Should two individuals match on the 12 marker test and desire to narrow down the general timeline, at which point they possibly shared a common ancestor, a 25 marker test is available for an additional $ 90.00 US. No additional sample is required.

       Should you match on the 25 marker test and desire an even narrower general timeline a 37 marker test is available for a further $ 59.00 US. No additional sample is required.

       The company performing the test will retain your sample for 25 years and your results will become part of the worldwide human genome project. 

       Needless to say, there is no point in male members of a single family each applying to be tested. A single representative sample is all that's necessary. 

       Once you have registered and paid the fee a test kit will be mailed to you. A sample is taken by your rubbing a cotton tipped swab on the inside of your cheek. It is imperative not to contaminate the sample! Don't be kissing your wife, girlfriend, co-worker or dog prior to taking the sample. HA! 

DNA Testing

      It must be understood by the participant that DNA testing is not an exact science! The interpretations of the results are based on statistical probabilities, not absolute certainties. 

     The theory (and that's all it is at the current time) is that the vast majority of European men shared a common ancestor tens of thousands of years ago. This common ancestor passed on his Y-chromosome unchanged to his sons, who in turn passed it on unchanged to their sons and so on. However, mutations in this Y-chromosome occurred at random intervals that were passed on to succeeding generations of males. These mutations are theorized to have occurred only once in every 500 generations. Therefore, by comparing the degrees of difference in the test results of two males of European origin, we can determine the probabilities of their having had a common male ancestor within certain numbers of preceding generations. It should be noted that due to the random nature of the mutations, there is a possibility, however slight, of your having an exact match with someone with whom you shared an ancestor a thousand years ago, but having a small difference with your own biological son.

     There are many detailed explanations on the theories involved in DNA analysis available on the internet. We suggest that you read more on this subject before considering your participation in this project.

The Results

    Because you share a rather uncommon surname as well as a country of origin with the other participants of this study, there is already a probability that you also share a common ancestor. How high that probability is you'll have to decide for yourself, given what you know of your lineage and, specifically, the locality in which your known ancestors lived. If your ancestors are Baths from Bristol and your test results match another participant whose ancestors are also from the same'll have to decide for yourself. 

    Added to this existing probability are the probabilities derived from comparing your test result with those of the other participants. Theoretically, if you score 12 / 12 with another individual there is a 50% probability that you shared a common male ancestor sometime within the preceding 14 generations ( Approx. 350 years, 1655 - 2005 ) and a 90%  probability that this occurred within 48 generations ( Approx. 1200 years, 805 - 2005 ). Medieval records indicate that the Bath / Bathe surname may have been first adopted in the mid 1100s, 850 years ago or 34 generations. lf all the Bath / Bathe participants should match 12 / 12 this would indicate only a 76% probability that they all shared a common ancestor within that timeframe. 

    These are rather long odds, but the fact that these participants also share the same surname should certainly shorten them. For further illustration, should all of these participants opt for a 25 marker test and score 25 / 25 there is a 95% probability that they shared a common ancestor within the above 850 year timeframe, a 90 % probability that this occurred within 575 years and a 50 % chance that they are closely related within 175 years. Again, sharing the same last name should increase this probability. 

    As stated above, it is possible, however slight, that a father and son may not have fully identical markers in their DNA. However, multiple mismatches greatly decrease the probability that two individuals shared a common ancestor within recorded time. Remember that the theory is that we all shared a common ancestor at some point, however long ago.

   If most of the other participants' tests closely match one another and yours doesn't, despite having the same last name and country of origin, it may raise more questions than it answers. Did you derive your surname from some other source? Did one of your grandmothers have an illegitimate child that became your ancestor ? Was your male ancestor adopted ? Etc.

   If too many of the study participants, who meet the participant criteria, have dissimilar results then we must conclude that a single, medieval family is not the source of the Bath / Bathe families.

Publication of the Results

    Initially, the test results will only be shared among the participants. As the number of participants grows and the data collected becomes of use for family genealogists, the results will be presented on this web site. No personal information pertaining to the participants will be published other than a few details regarding their known antecedents, such as their earliest known male ancestor, the county / town / village where the family was located etc. .  Should you wish to contact any of the participants this may be done through the project administrator and only with the consent of the participant.

How to Join

If you have any questions, regarding this study, please contact the Project Administrator, Mr. Martin Bath of Devon.

   Having carefully read the above information and having satisfied yourself that this project is of interest and value to you, you can click on either of the hyperlinks below to register and begin your participation.

Family Tree DNA

  We suggest that you read about the laboratory that will be doing your test, then Click on "Surname Projects", "B" in the index, "Bath, Bathe, de Bathe" on the projects list.

  Or go directly to the registration page.  Bath / Bathe / de Bathe DNA Project

Whether you decide to join us or not, we wish you all the best !

                                                                                The current Bath participants from England, Australia and Canada.