|DEPARTMENT OF GENETICS - Prof Mark A. Jobling|
We are all interested in our origins, and many of us research our own family trees. Most of us get our surnames from our father, and those of us who are males also get a section of our genetic material (DNA) from our father too. This is the Y chromosome, which is responsible for making males (while females have two X chromosomes, males have one X and one Y). We want to know how different kinds of Y chromosomes relate to different surnames. Do all males who share a particular surname share a kind of Y chromosome, and thus a common ancestor ? And what can we learn from this about the history of Britain? This research is not only of interest for genealogists, but also has forensic relevance (surname prediction from crime-scene samples? ), and medical importance. Surnames are often used as a simple way of looking at the 'structure' of a population, and also to help predict risks of diseases such as cancers and cardiovascular disease. In this study we aimed to be able to put these studies on a sounder scientific basis by using modern molecular genetic methods to test some of the assumptions which underlie them.
The particular aim of the project was to explore the relationship between Y chromosome types and British surnames: since both are patrilinearly inherited (through the paternal line) we expect some correlation between the two, but it is not clear how strong that correlation is likely to be, or what factors have affected it. By collecting male volunteers sharing surnames, for a number of names, we aimed to describe the patterns of variation within surnames, and then use computer methods to decide which factors were most important in determining these patterns, in particular:
To do this, Turi recruited over 2500 unrelated men, chosen geographically randomly, who provided cheek-swab samples from which she extracted DNA. She typed a set of 17 binary markers to define haplogroups, and a set of 17 Y-STRs (or microsatellites) that allow finer-scale variation within haplogroups to be defined (see here for definitions of these terms). The set of 2500 men included a control group not sharing surnames, plus sets of men (between 2 and 180 in number) who shared a surname, including recognised surname spelling variants.
Our previous work on the connection between surnames and Y chromosomes was in the Thomas Jefferson paternity case , and in the geographical subdivision of modern Irishmen on the basis of their surnames , work that was initiated and continued by Dan Bradley at Trinity College, Dublin.
We published our study of 150 pairs of men sharing surnames in February 2006 , in the journal Current Biology. That study aimed to examine the relationship between Y chromosomes and British surnames in a broad way - many names, very few samples. It showed a high degree of coancestry that justified a larger scale study. You can Download the final pre-publication version of the article here. Our more in-depth study of 40 individual surnames has been published  in the journal Molecular Biology and Evolution, and will be of greater interest to volunteers who belong to these study groups. We again show a high degree of coancestry that increases as surname frequency decreases, the dominant effect of genetic drift in patterning variation within surnames, and a remarkable difference between Y-diversity within British and Irish surnames.
We have also published studies of an African lineage in a Yorkshire surname , the lineage of President Thomas Jefferson , and a paper about the risk of accidentally diagnosing infertility from genealogical testing .
This project has now been superseded by a Wellcome Trust funded project grant, running from December 2007 to November 2010:
1. Jobling, M.A. (2001) In the name of the father: surnames and genetics. Trends Genet. 17, 353-357.
2. Jobling, M.A., Pandya, A. and Tyler-Smith, C. (1997) The Y chromosome in forensic analysis and paternity testing. Int. J. Legal Med. 110, 118-124.
3. Foster, E.A., Jobling, M.A., Taylor, P.G., Donnelly, P., de Knijff, P., Mieremet, R., Zerjal, T. and Tyler-Smith, C. (1998) Jefferson fathered slave's last child. Nature 396, 27-28.
If you are interested in the Jefferson/Hemings case, visit the Monticello website, where a detailed report is available.
4. Hill, E.W., Jobling, M.A. and Bradley, D.G. (2000) Y-chromosome variation and Irish origins. Nature 404, 351-352.
5. King, T.E. et al. (2006) Curr. Biol. 16, 384-388. Genetic signatures of coancestry within surnames. You can download the final pre-publication version of the article here, and obtain the published pdf from the Current Biology website.
6. King, T.E. and Jobling, M.A. (2009) Mol. Biol. Evol. 26, 1093-1102. Founders, drift and infidelity: the relationship between Y chromosome diversity and patrilineal surnames. Article available as Open Access.
7.King, T.E. et al. (2007) Eur. J. Hum. Genet. 15, 288-293. Africans in Yorkshire? - the deepest-rooting clade of the Y phylogeny within an English genealogy. Article available as Open Access from journal website.
8.King, T.E. et al. (2007) Am. J. Phys. Anthropol. 132, 584-589. Thomas Jefferson's Y chromosome belongs to a rare European lineage.
9.King, T.E. et al. (2005) J. Med. Genet. 42, 366-368. Inadvertent diagnosis of male infertility through genealogical DNA testing. Article available as Open Access from journal website.
Last updated: 14th April, 2009
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