Finding History in the Genome

ResearchBlogging.orgWe are starting a little bit of genetic genealogy in our household. I’ve always have been an avid genealogist and with an adopted child we’ve been found it interesting and helpful to delve a bit deeper into our heritages in a way we couldn’t have 10 years ago. So, I’m a bit aware lately of studies of historical and genetic links to our backgrounds…

A study in this month’s American Journal of Human Genetics suggests that the history of the spread of Islam and the crusades can be found in the genomes of the male population in Lebanon. The study found that…

926 Lebanese men were typed with Y-chromosomal SNP and STR markers, and unusually, male genetic variation within Lebanon was found to be more strongly structured by religious affiliation than by geography.

Their hypothesis was that migrations within historical times contributed to difference. The data was from the Genographic Public Participation Project (National Geographic). Their conclusions?

Y-haplogroup J(xJ2) was more frequent in the putative Muslim source region (the Arabian Peninsula) than in Lebanon, and it was also more frequent in Lebanese Muslims than in Lebanese non-Muslims. Conversely, haplogroup R1b was more frequent in the putative Christian source region (western Europe) than in Lebanon and was also more frequent in Lebanese Christians than in Lebanese non-Christians. The most common R1b STR-haplotype in Lebanese Christians was otherwise highly specific for western Europe and was unlikely to have reached its current frequency in Lebanese Christians without admixture. We therefore suggest that the Islamic expansion from the Arabian Peninsula beginning in the seventh century CE introduced lineages typical of this area into those who subsequently became Lebanese Muslims, whereas the Crusader activity in the 11th13th centuries CE introduced western European lineages into Lebanese Christians.

It confirms what we might have guessed, evidence of those early migrations/invasions/admixtures into Lebanon persist in the population hundreds of years later. It also somewhat surprises me at how well it has persisted and those populations remain separated (in general). But the thing I find most fascinating about this is how, as we expand our research in projects like this, HapMap and others, we are starting to unravel, confirm and/or debunk so many of our understandings of human history and migrations.

It’s fascinating as a biologist and as an individual I look foward to finding at least a bit more about our own family migrations.
ZALLOUA, P., XUE, Y., KHALIFE, J., MAKHOUL, N., DEBIANE, L., PLATT, D., ROYYURU, A., HERRERA, R., HERNANZ, D., BLUESMITH, J. (2008). Y-Chromosomal Diversity in Lebanon Is Structured by Recent Historical Events. The American Journal of Human Genetics, 82(4), 873-882. DOI: 10.1016/j.ajhg.2008.01.020