The Filby Association™ DNA Project

A SURNAME DNA STUDY ~ By Jim Filby

Deoxyribonucleic Acid or DNA.

The human body contains approximately 100 trillion cells; inside every one of those cells (except the red blood cell) is a nucleus that contains a copy of our DNA. This is grouped into 23 pairs of chromosomes that are made up of four DNA bases. These bases are Adenine, Guanine, Thymine and Cytosine. When we refer to a particular piece or sequence of DNA it could be described as similar to: AATGCTCCCTTTTAAA or any combination of bases.

One member of each of our 23 pairs originates from our mother and the other from our father. With 22 of the pairs the two chromosomes are similar, and from time to time they interchange material between each other. The 23^rd set termed ‘X’ and ‘Y’ are the sex chromosomes. Females have two ‘X’ chromosomes, and therefore their similarity permits exchange. Males however have one ‘X’ from the mother and a ‘Y’ from the father and their dissimilarity does not permit exchange.

This means that the major part of the ‘Y’ chromosome of every living male directly resembles that of his father, his grandfather and all his common male ancestors. However when the DNA within the male ‘Y’ chromosome is copied from generation to generation, small mistakes or polymorphisms are occasionally made in the DNA sequences. These mistakes that occur every few hundred years or more are found at particular locations loci on the chromosomes and are subsequently inherited. These Single Nucleotide Polymorphisms (SNP called snips) can be used to determine our male ancestry.

DNA is involved in the production of proteins that are responsible for most of our physical make-up and is termed genic or coding DNA. However 97% of DNA is not used in this way and does not seem to have any apparent useful purpose, and is called junk or non-coding DNA. Within this junk DNA at certain loci or markers are lengths of DNA with a repeating sequence, called Short Tandem Repeats (STR) of usually three or four chemical bases; for example GATAGATAGATAGATAGATAGATAGATA. These short sequences are called Microsatellites; there are longer sequences normally 10 to 50 base pairs, these are called Minisatellites.

A number of markers (up to 67 at the moment) have been identified and are given DYS numbers (DNA Y chromosome Segment). At each marker the number of times the STR repeats is counted, this number called an Allele Value (pronounced Al-eel) is assigned to that marker. The original number of markers tested was 12, now tests of 25, 37 or 67 markers can be carried out. A specific set of numbers (a population group) defined by these specific SNP mutations defines your Haplogroup.

Our Haplogroup cannot on its own determine with any degree of accuracy who our ancestors are, it can however be used along with documentary evidence prove or disprove any assumptions we may make from the documentary evidence. The information it can tell us in a surname study are:

1) Does the surname have a single ancestor or are their multiple ancestors.

2) Determine any problems we may have with surname variants.

3) Where we have multiple trees it can point us to where one tree could join onto another tree.

4) It can also tell us if we have put an ancestor onto the wrong tree.

5) It can show us where a possible surname change has occurred.

6) Or it can point to non-paternity events, i.e. adoption, illegitimacy, or a widow re-marrying and giving the children from her previous marriage her new husband’s surname.

A Filby DNA Study.

I have started a DNA project for the Association with ‘FamilyTreeDNA’ and as such I have enlisted the help of three male members who have each taken a 37 marker DNA test. These members will remain nameless and will be referred to by a designated code. Two of the members are on the same tree separated by 6 generations; these two will be referred to as ‘1A’ and ‘1B’; the third member who is on a separate tree will be referred to as ‘2’.

Looking at the Allele values for just the first 12 markers in table 1 below, what can we determine?

Table 1.

1) 1A and 1B are in all probability not related. They are showing 8 markers with mutations some with more than one mutation? This could be down to the following reasons?

a) We have made an incorrect assumption and put one of their ancestors on the wrong tree?

b) They are both on the correct tree and there has been a non-paternity event?

2) If we have made an incorrect assumption, which is possible and placed one of them on the wrong tree; it will mean that we may have a surname with multiple ancestors?

3) 1B and 2 have all 12 markers that are identical. This indicates that there is a 50% probability that they both have a Most Recent Common Ancestor (MRCA) within 7.4 generations? (See table 2). Both are related and the two trees should join somewhere?

Table 2 above taken from the book "DNA and family History - by Chris Pomery"

4) Item 3) could also be a big pointer to the fact that person 1B has been put on the wrong tree?

A lot of further research and further DNA test will be required to determine exactly the reason for the above; and may take some years to find the answers. But even with only three participants and using only 12 markers we have identified a number of areas requiring further research.

At the moment doing any further analysis on the other 25 markers for participant 1A would be meaningless until we find another Filby with the same or similar 12 marker haplotype. However looking at markers 13 to 25 and 26 to 37 for participants 1B and 2 we have the following:

Table 3 - 13 to 25 markers

Table 4 - 26 to 37 markers

Looking at table 1, 3 and 5 we have only 3 Allele values that are different, and these show only 1 mutation on each of the 3 markers that are different. If we look at table 2 this gives us a slightly larger value for our MRCA of 9.4 generations with a probability of 50%.

Table 5 above taken from the book "DNA and family History - by Chris Pomery"

However looking at table 5 gives us a range of between 2.8 and 22.3 generations of finding a MCRA. What this table tells us is that participants 1B and 2 are definitely related with their Most Common Recent Ancestor within 22 generations, and they could be related within 3 generations.

Without giving away the participants names, what I can say is that one of the last two participants mentioned is on our largest tree which goes back 17 generations; this means that there is a very high probability that the second participant is also on that tree. All we now have to do is look for the written evidence to find out where the second participant joins the tree.

 

One for the ladies.

So far we have discussed the Y chromosome and the Y-DNA tests that inform us about the Paternal line; there are tests that give information about the Maternal line these are called mt-DNA or Mitochondrial DNA.

If you look at the picture of the human cell, at the beginning of this article, you will see a Nucleus where the main DNA and the Y chromosome is found. You will also see some Mitochondria, there are in fact a lot more, than the four Mitochondria shown in the picture of the cell; in fact in each cell there are in the region of hundreds of mitochondria.

During fertilisation, the mt-DNA carried in the tail of the sperm is lost when the sperm discharges its nucleus into the egg. The mt-DNA found in the egg is nonrecombinant, so that it is passed down unchanged, apart from mutations, along the female line.

There are however a number of differences between the two DNA: 1) the mt-DNA is very small, about 0.0003% of the length of the Y chromosome found in the nucleus. 2) It has relatively more polymorphisms. 3) They mutate about 10 times faster than the DNA found in the Y chromosome.

The tests on mt-DNA are similar to those tests on the Y-DNA; they are taken in the same way, and the costs are similar.

Conclusions.

Y-DNA studies can be used in One Name (Surname) studies to prove or disprove our assumptions made from written research data, and will point us to where further research is required. Mt-DNA studies are used to determine evidence on the maternal (female) line.

From the data shown above it would appear that evidence from a 12 marker test is more than useful to show us where some errors have occurred and where further research is required; only where there are problems in analysing the results or for deeper research would we need either 25, 37 or even 67 marker tests. Although some genealogists would argue that a 25 marker test should be the minimum.

The Future.

The various tests are quite expensive, they do however reduce in cost by about 70% if a project is started with a testing company; I have started a project with a company called FamilyTreeDNA where the above Y-DNA-37 tests where carried out. If you require information about current prices please contact me.

I have promised that the money we raise at the moment for the Association will not be used to finance the DNA project; I will however try and raise extra money to use towards this project, which is what I have done to finance the first three tests. As soon as I have enough for a further test I will approach others to participate.

We have well over 170 trees and some joined to make a total of 100 master trees. I have not analysed the number of surviving male members, but I am sure that there could be as many as 200 males who could be tested; not all of them will be members of the Association. However, if we carried out Y-DNA-12 tests on them all it would cost £11,000, a cost the Association could not afford. Therefore we would need to be selective on whom we test, this selection being driven by our researchers.

However, if any of you would like to volunteer and pay for your own tests you are quite welcome to get in touch with me. The main criteria is that you are a male descendant on the Filby or its variants (Filbey, Filbee, Philby or Philbey) line, and that you are separated by a minimum of 3 generations from anyone else already tested, and that you are on one of our trees.

You can of course visit www.familytreedna.com/public/filby/ and join there. I would however strongly suggest if you want to join the “Filby DNA Project” you email me first and I will join you, or you join and email me to let me know. The reason I ask this is that I will first of all point out all the advantages and disadvantages of having a test done; you would of course, as are the first three participants, remain anonymous. One of the worst disadvantages is that it could prove that you are not really who you think you are.

If you wish to read and understand more about this subject two good reads are: DNA and Family History by Chris Pomery - ISBN 1-903365-70-8 published by the National Archives (now out of print but you will find a revised version "Family History in the Genes" by Chris Pomery ISBN 978-1-905615-12-4 sold by the National Archives at £7.99) and DNA & Genealogy by Colleen Fitzpatrick & Andrew Yeiser - ISBN 0-9767160-1-1 published by Rice Book Press. Both these books were used by me in writing this article.

Please note: Assorted research data, as well as tables 2 and 5 where taken from the book "DNA and family History - by Chris Pomery" For further information about the Filby Association DNA project or if you are interested in joining the project please contact our Manager Jim Filby via e-mail Email Manager