Y-DNA SNP Database Characterization

Vertical bar chart showing the five most densely sampled countries for Y-DNA: Ireland, Finland, UK, Norway, and Sweden.

Analysis of sample count and sampling density of the Y-DNA SNP results in the Family Tree DNA results database. Comparison of World, European, and British Isles figures by country, Y haplotype, and phylogenetic tree branch count.

English surnames: Plural Origins and Emigration

Scatter plot of Monte Carlo simulation of surname population simulations

Comparison of the distribution of English surnames in modern England versus former colonies with distinction between the relative rareness of the surname and the overall population of persons using that surname. Geographical surname patterns, Monte Carlo population simulations, and Y-DNA results are considered. Some examples using very early written sources are also used to address the controversy of single versus multiple surname origins in England. A reassessment of the DNA data and conclusions of King and Jobling’s 2009 results is also made.

Using STRs for Intra-Family Y-DNA Comparisons: Segmenting Markers

Notional tree diagram of four descendants of common ancestor using a segmenting marker.

Counting Y-DNA STR differences is a poor discriminator for members of the same family. Unless a very large number of markers are used, matching cannot be used with a statistically significant degree of accuracy to establish whether someone is more closely related even to second cousins. However there are other methods that may be used to distinguish degrees of relatedness. We present a simple and useful test which involves finding a “segmenting marker” which can establish relative consanguinity with some accuracy, and we give a real-life example of its use to show from which of two 17th Century brothers a man of partly unknown origins descended.

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

Bar Chart of Irish County Distribution and Map Plots of Placenames for Donohoe test subject.

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.