Those thousands of knights went to the Middle East during the 11th-13th centuries to free the Holy Land from the hands of the Muslims, but despite their religiosity, they found some moments to have some hanky-panky. In the end, their wives from England, France, Germany and Italy
were far away and many ended mixing with the inhabitants.
In a recent research published in the American Journal of Human Genetics, DNA "forensics" detected their lustful behavior. This research is part of the Genographic Project, which aims to determine historical human migrations via DNA.
Some Christian men from Lebanon carry a DNA signature in their Y chromosomes which is specific for the western Europe. Similarly, many Lebanese Muslim men were more likely than Christians to possess a genetic mark connected to the waves of Arab immigrants who came in the area coming from the Arabian Peninsula during the expansion of the Islam in the 7th and 8th centuries.
Of course, these variants represent a very small percentage of the overall Lebanese genetic make-up, and that Christians and Muslim Lebanese have more common heritage, connected to previous populations (like Phoenicians, other Semites and Greeks). The genetic mark originated in the Arabian Peninsula was also found by other similar researches focused on the genetics of Middle Eastern and North African populations.
The Y (male) chromosome comes only from the paternal side, from father to his son(s). In time, the genes located on the Y chromosome store mutations (small DNA changes). During the human evolution, these mutations created groups of male chromosomes (haplogroups), connected to geographical populations. This means they can track down migration.
The Y chromosomes of 926 Lebanese males were analyzed and resulted that Lebanese haplogroups were more connected to religion than geography. The WES1 mark, typical for west European populations, was discovered on the Y chromosomes of the Christian Lebanese men.
"It seems to have come in from Europe and is found mostly in the Christian population. This is odd because typically we don't see this sort of stratification by religion when we are looking at the relative proportions of these lineages - and particularly immigration events," Dr Spencer Wells, director of the Genographic Project told BBC News.
"Looking at the same data set, we saw a similar enrichment of lineages coming in from the Arabian Peninsula in the Muslim population which we didn't see [as often] in the Christian population," he added.
The J1 mark is typical in populations rooted in the Arabian Peninsula, where Islam expanded from.