Friday, May 24, 2013

Finding your Irish surnames origins

At the last FTDNA Administrators Conference, Dr Tyrone Bowes, PhD, gave a talk showing how one could find the origins of an Irish surname. It was a fascinating talk that he updated for Who DO You Think You Are. Links to both talks appear on this page. He has recently published a paper on it in the Surname DNA Journal:

Using Y Chromosome DNA Testing to Pinpoint a Genetic Homeland in Ireland


Analytical techniques were developed combining the Surnames of Y-STR DNA matches, the 1911 Census of Ireland, and geographical place names to pinpoint the ‘Genetic Homeland’ of five (5) of eight (8) individuals used as test cases. Four (4) of the individuals were natives of Ireland and one (1) was a native of Scotland. The Genetic Homeland concept is based on the area where founding ancestors first adopted surnames and lived for hundreds or thousands of years. Although the surnames adopted may have been diverse and many or all descendants with a particular surname may have moved away from those areas, the geographical place names and other descendants from the same patriarch often remain in those geographies today.

Thursday, May 23, 2013

Do you have a Family Tree at 23andme?

I am finding a number of Family Tree entries for married females that list them by the husband's last name. Looking at the data entry page in Family Tree I see that there is a separate line for Last Name and another line for Birth Name. The usual best practice is to have both Last Name and Birth Name be the BIRTH NAME for a married female. This makes it much easier for someone to see the connecting surname when looking at the limited tree shown by 23andme.

Wednesday, May 08, 2013

Although confined to western European populations, this article seems to provide empirical evidence to validate several earlier papers on the theoretical relatedness of humans throughout the world.

Ralph P, Coop G (2013)

The Geography of Recent Genetic Ancestry across Europe.

PLoS Biol 11(5): e1001555. doi:10.1371/journal.pbio.1001555


The recent genealogical history of human populations is a complex mosaic
formed by individual migration, large-scale population movements, and other
demographic events. Population genomics datasets can provide a window into
this recent history, as rare traces of recent shared genetic ancestry are
detectable due to long segments of shared genomic material. We make use of
genomic data for 2,257 Europeans (in the Population Reference Sample
[POPRES] dataset) to conduct one of the first surveys of recent
genealogical ancestry over the past 3,000 years at a continental scale.

We detected 1.9 million shared long genomic segments, and used the lengths of
these to infer the distribution of shared ancestors across time and
geography. We find that a pair of modern Europeans living in neighboring
populations share around 2–12 genetic common ancestors from the last 1,500
years, and upwards of 100 genetic ancestors from the previous 1,000 years.
These numbers drop off exponentially with geographic distance, but since
these genetic ancestors are a tiny fraction of common genealogical
ancestors, individuals from opposite ends of Europe are still expected to
share millions of common genealogical ancestors over the last 1,000 years.

There is also substantial regional variation in the number of shared
genetic ancestors. For example, there are especially high numbers of common
ancestors shared between many eastern populations that date roughly to the
migration period (which includes the Slavic and Hunnic expansions into that
region). Some of the lowest levels of common ancestry are seen in the
Italian and Iberian peninsulas, which may indicate different effects of
historical population expansions in these areas and/or more stably
structured populations. Population genomic datasets have considerable power
to uncover recent demographic history, and will allow a much fuller picture
of the close genealogical kinship of individuals across the world.