Genealogy Through DNA

Project Members Markers


Results of participents

Y-DNA is passed from father to son unchanged for upwards to 20 or more generations.It is particularly useful in proving or disproving a relationship when the documentation is not provable. Y-DNA can also help discover links to family lines that document research has not uncovered.


Results of participents

mtDNA is not as usefull as is Y-dna. It is passed from mother to child unchanged for thousands of years, but since a females surname changes with marriage, it isn't as usefull in tracing family lines.

Our Origins

Where We Came From

Associated Surnames


Caer, Car, Care, Carr, Carrach, Carre, Cear, Cer, Corr, Kar, Kare, Karr,Kaar, Karre, Kaare, Kaer, Kar, Kaurr Kay, Ker,Kear, Kehr, Keire, Kere, Keor, Kerr,Kerre, Keyr, Kier, Kurr,

Carrach is also the Gaelic form of Kerr in Arran ( ie One Of The Kerr's) The name Carr in Ireland is not just an anglicized form of the Scottish Kerr only.During the time of the penal laws in Ireland, a number of different native Gaelic Sept names were anglicized to Carr also. It being decidedly unpopular if not downright dangerous to be either Catholic or Gaelic at that time

These include the O'Carraigh Sept of County Louth,

From Ulster the Anglicized form of the Gaelic Ó Carra ‘ descendant of
Carra’, a byname meaning ‘spear’.

From Donegal The Anglicized form of the Gaelic Mac Giolla Chathair,
a name meaning ‘son of the servant of The Mac Giolla Domhnaigh Sept of County Derry

And the O'Ceardain Sept of County Donegal.

The Kerr surname also absorbed examples of the German surname Kehr.
Kehr from Middle High German kere ‘bend’, ‘corner’, hence a topographic name for someone living near a bend in a road or near a field named with this word. The name is common in Tyrol (where it is also a place name from which the surname may have arisen) and in adjoining parts of Switzerland. possibly a short form of a personal name, Kehri or Kehrein, derived from the Roman personal name Quirinus, which was borne by several early Christian martyrs. Dictionary of American Family Names, Oxford University


Genalogical Objectives

  • Identify others who are related
  • Prove or disprove theories regarding ancestors
  • Solve "brick walls" in your research
  • Determine a location for further research
  • Validate existing research
  • Develop a DNA database for future researcher

Analysis of the mutations in the Y-chromosome can also be used to estimate the Most Recent Common Ancestor (MRCA) in terms of number of generations since the separation occurred.

If your Carr research has hit a “stone wall”,DNA analysis could be the break through you have been looking for, and push your genealogy research back generations, by finding connections to other Carr family Lines.


Genealogical DNA testing is still in it's infancy, having only been available since 2000.
As the data base expands with more and more individuals being tested, it cannot but help become a greater genealogical asset as the time goes by.
However, since we are presently interested in tracing surnames, which are usually passed from father to son, the testing of the Y-chromosome DNA and SNP test is what we are interested in.

For more information on DNA and Y-chromosome testing see

DNA 101


The Carr Surname DNA Program

Your membership in the program will require the submission of genealogically relevant DNA results.

Carr / Kerr Family DNA Contact: John Carr

Family Tree DNA


A Word Of Caution

There is always a possibility that you could get a disappointing test result. Samples can vary by three or more markers from the main group, and may do so for a number of reasons.

One reason could be that they represent distinct lines, either older or younger than the currently observed and most frequent line. Another is that there could have been a “non-paternal event” at some unknown past time.

  • There are several possible types of non-paternal event other than
    a pregnancy gained outside of a marriage.
  • For example, a child could have been adopted and given the Carr name; a man could have taken the Carr name when he married a Carr daughter; a Carr man could have married a pregnant woman whose husband has died; a couple where the wife is the Carr, could have choosen to give their children the Carr name for various reasons; a clerical error in recording administrative data may have assigned a Carr name to the wrong person, and so on.
  • It should be stressed that adoptions have been quite common in every age (i.e.. parents having died of disease or by war and a relative took in the children and raised them with their name; or a young daughter had a child out of wedlock and the parents raised it as their own).
  • Some may not wish to see a result indicating a “non-paternal event” but we are all Carrs legally, a small sample size could be misleading. One might get a DNA sequence which suggests a “non-paternal event” but they just could be of the original Carr blood line.

For instance;

Twenty people are tested and 19 are very similar but the last is clearly different.
It could turn out that the 19 descend from the same person 300
years ago and this person was an adopted Carr.
While the other is of the original Carr blood line going back 800 years.

The Carr surname could probably have come from at least four distinct groups;

  • Normans who appear to have established the name in Scotland, in the twelth century.
  • The descendants of people who have lived there since the last ice age, and who adopted the name
  • The local britannic celts mixed with other people who came in with the Romans, who also
    adopted the name.
  • And the Irish Gaels that anglicsized their names to Carr during the time
    of the penal laws, to avoid persecution.