Icelandic names and consanguinity

In the "searching the news for something not utterly horrible" category, there is this recent story on the Islendiga-App - the App for Icelanders.  Basically, this smartphone app allows any two individuals to "bump phones" and discover how closely related they are as a preventative measure against inbreeding.  Apparently, the app makes use of the Islendingabok, the online genealogical database for Icelanders which cross-references the extensive census records, church registries and personal genealogies with molecular DNA data.  I should note that, in reference to a major personal research interest, Iceland is probably the only western nation where traditional isonymy research is ineffective due to the use of patronymic (and occasionally matronymic) name systems.  In other words, Icelandic children derive their surname from the first name of their father (and occasionally mother).  For example, my surname would be "Thomasson", whereas my son would be "Kevinsson."  This pretty much invalidates the surname as a genetic proxy, although in the case of Iceland the extensive geneaological records provide an alternative for assessing consanguinity via archival methods.

Surnames and Vikings

Just finished reading Leif the Lucky to my 2 year old, who sat with very un-bedtime like, rapt attention through the whole thing.  This reminded me of a recent article in Molecular Biology and Evolution regarding the covariance of Scandinavian-derived surnames and Y-chromosomal signatures in northwestern England.  Lest I begin to sound like a broken record, here we have yet another example of how classic marker studies are being validated by modern molecular methods.


Bowden, G et al., 2010, Excavating Past Population Structures by Surname-Based Sampling: The Genetic Legacy of the Vikings in Northwest England.  Molecular Biology and Evolution 25 (2): pp. 301-309.

More on diseases and surnames

As a follow-up on the previous post, here is another journal article using surnames as potential indicators of disease inheritance (in this case, chronic hypothyroidism).  What is interesting about this study is that Rocci employs two fairly novel methods for isonymy research.  One is the rarefaction method developed by Howard Sanders to measure species richness, and the other is a statistical randomization method. 

References

Rocchi, M.B. 2006. Surnames as markers of pathologies-two statistical techniques and their applications.  Coll. Antropol. 30: 383-385.

Surnames and cancer

After my first few postings introducing surname genetics (isonymy), I wanted to bring up a very important practical application of this research; the application of surname studies to cancer research.  In a 1992 study on the potential genetic influence on certain cancers, Holloway and Sofear compared the rates of various cancers identified in Scottish males with the coefficent of relatedness (Random Isonymy / 2) derived from surname data.  They were able to conclude that a strong genetic component underscores colon and prostate cancer, with a lesser genetic influence on stomach and rectal cancers.  This study underscores just how useful surnames can be as simple, readily available markers of kinship.

References

Holloway, S.M. and Sofaer, J.A. 1992. Coefficents of relationship by isonymy among registrations for five common cancers is Scottish Males.  Journal of Epidemiology and Comunity Health 46: 368-372.

Sources for Surname Data

Continuing from the previous post on surname studies, today I'll talk a bit about where to find surname data.  Historically, there have been three main sources of data:  marriage records, census data and directories (later phonebooks).  Marriage records are used for measuring non-random isonymy, which I will discus in a later post.

Census data is useful since state and federal censuses often contain additional demographic data, such as vital statistics (births, deaths, marriages), as well as state or country of origin, which can aid in immigration studies.  When using census data it is generally accepted practice to utilize a single generational component, usually the heads of households only.  

Another source of data are town directories.  Throughout the 19^th century, directories of town residents were often produced, though somewhat irregularly.  These directories essentially functioned like phonebooks without the phone number, giving the name of the head of household and address.  Directories have the advantage of being typed records, rather than handwritten census records.  With the advent of the telephone, naturally the phonebook took the place of directories.  Phonebooks have been used extensively in isonymy studies, particularly when the information is available via CD-ROM.

Beyond the three major sources listed above, data sources are only limited to the creativity of the researcher.  Indeed, any specific record of individuals may represent a biological sample of some population.  For example, Gabriel Lasker utilized militia roles from the Revolutionary War as random samples of males from bounded populations.  Another possible source of data are cemeteries.  Many cemeteries include grave markers listing married couples, which would constitute a source of marital isonymy data.

One of the most significant developments for surname research is the fact that many of these data sources are now becoming available online.  Historical societies and genealogical websites are beginning to transcribe census and historical directory data on to the internet.  Of course, you are taking a risk of sorts when utilizing transcribed data alone since you are relying on the accuracy of the transcriber.  This may be especially problematic when the information was originally hand-written.  Then again, much of this work is being done by dedicated volunteers, who can be quite adept at both translating hand-writing and identifying alternate spellings of words.  When in doubt, check out the hard copies yourself at the county offices or local historical society.