The general heterogeneous composition of Hgs seen in our Sicilian data is consistent with similar patterns observed in other major islands of the Mediterranean, like Sardinia and Crete, possibly reflecting the complex histories of settlements in these islands during the Holocene.
Friday, November 14, 2008
Y chromosomes of Sicily
In May of 2008, Cornelia Di Gaetano et al submitted an article to the European Journal of Human Genetics studying the Y chromosome makeup of the island of Sicily. Sicily has one of the highest frequencies of Haplogroup J2 (M172) in the mediterranean. J2-M172 made up 33% of the Y chromosome signatures on the island and was non-randomly distributed occurring at higher frequencies in the eastern areas of the island. This distinction was evident in the subclades, M67 and M92, which have previously been linked to Greek and proto-greek colonization. Both M67 and M92 were twice as frequent on the eastern portion of Sicily which displays more archaelogical traces from the Greek classic era. Even the paragroup of undistinguished J2 haplotypes (M172) was more than twice as frequent in Eastern Sicily. One of the more interesting subclades, referred to as J2a1k (DYS445=6) showed an interesting non-random distribution in Sicily. This subclade is also commonly referred to as J2a1h (ISOGG) or J2a-Lambda (J2 DNA Project). Most striking was differences in frequencies between Mazara Del Vallo and Sciacca. Mazara Del Vallo is a port city established by the Phoenicians in the 9th century B.C. while Sciacca, known as Thermae in Greek times, was founded in the 5th century B. C. by the Greeks. These 2 cities, founded by different groups are only 57 KM apart. Yet 11.11% of the Y chromosomes in Mazara del Vallo were J2 M172 with DYS 445=6 while this subclade was absent from the sample data from Sciacca. Trapani, another port city in Western Sicily also exhibited high levels of J2-M172 with DYS 445=6 at 9.09%. This subclade was absent from the inland cities of Santa Ninfa and Piazza Armerina and the northern Sicily town of Caccamo. The data seems to suggest that J2a1h (J2a1k)'s distribution is stronger in coastal regions of Western Sicily and more rare in inland and Eastern parts of the island. The sole exception to this trend was the data from Troina which did report 10% J2 M172 with DYS 445=6. Overall the non-random and high levels of J2 on the island of Sicily seem to reflect the complex history of the island and might represent multiple migrations by multiple groups over various periods of the islands history.