E-M81

From Haplowiki

E-M81 is a Y chromosome haplogroup defined by the mutation M81. It is a sub-clade of E-M35. It's phylogenetic name according to the E haplogroup page on ISOGG's website is E1b1b1b.

Origins

E1b1b1b (E-M81) is the most common Y chromosome haplogroup in the Maghreb, dominated by its sub-clade E-M183. It is thought to have originated in the area of North Africa 5,600 years ago (Cruciani et al. 2004, Arredi et al. (2004)). It is colloquially referred to as the "Berber marker" for its prevalence among Mozabite, Moyen Atlas, Kabyle and other Amazigh groups, E-M81 is also quite common among North African Arab groups.

In this key area from Egypt to the Atlantic Ocean, Arredi et al. (2004) report a pattern of decreasing STR haplotype variation from East to West, accompanied by a substantial increasing frequency. This pattern the authors believe to be consistent with the hypothesis of a post Paleolithic "WP:demic diffusion" from the East. The ancestral lineage of E-M81 in their hypothesis could have been linked with the spread of Neolithic food-producing technologies from the Fertile Crescent via the Nile, although herding rather than agriculture. E-M81 and possibly proto-Afroasiatic language may have been carried either all the way from Asia, or they may represent a "local contribution to the North African Neolithic transition".

Distribution

E-M81 is generally found at frequencies between 40 and 80% in the Maghreb. This includes the Saharawish for whose men Bosch et al. (2001) reports that approximately 76% are M81+. In Egypt, highest reported frequency so far is 28.6 % in the Egyptian Western Desert (Kujanová et al. (2009)). E-M81 is also found in Canary Islands at 8.28% (Flores et al. (2001)).

In Europe, E-M81 is found everywhere but mostly in the Iberian Peninsula, where it is more common than E-M78 unlike in the rest of Europe (Adams et al. (2008)), and shows an average frequency of 4% (Adams et al. (2008)) in the whole peninsula (including 5.6% in Portugal, Beleza et al. (2006)), with frequencies reaching 8% in Extremadura and South Portugal, 9% in Galicia, 10% in Western Andalusia and Northwest Castile (Adams et al. (2008), see table) and 13 % in Cantabria (Capelli et al. (2009)). The highest frequency of this clade found so far in Europe has been observed at 40% in the Pasiegos from Cantabria (Cruciani et al. 2004). According to some authors (Gonçalves et al. (2005)), the presence of this haplogroup in Iberia likely reflects a pre-Moorish component shared with North African populations and indicates that "male Berbers constituted a long-lasting and continuous community in the country" while for others (Adams et al. (2008), Capelli et al. (2009)) it is mainly due to the medieval Moors which "confirms a general correlation between historical and genetic data".

At lower frequencies, E-M81 is also found in Sicily at 2.12 % (5 out of 236, Gaetano et al. (2008)), in continental Italy in the region across the southern Apennine mountains (East Campania, Northwest Apulia, Lucera) at 2.63% (5 out of 190, Capelli et al. (2009)) possibly due to "Frederick II’s relocation of Sicilian Arabs" and in France (Cruciani et al. 2004).

Presumably as a result of its old world distribution, this sub-clade is found throughout Latin America, for example 6.1% in Cuba (8 out of 132, Mendizabal et al. (2008)) and 5.4% in Brazil (Rio de Janeiro), (6 out of 112, Silva et al. (2006)). According to Silva et al. the presence of chromosomes of North African origin in Latin America can be explained by "a Portuguese-mediated influx, since this haplogroup reaches a frequency of 5.6% in Portugal quite similar to the frequency found in Rio de Janeiro (5.4%) among European contributors.". M81 has also been found among Hispanic men from California and Hawaii in the United States at 2.4% (7 out of 295, Paracchini et al. (2003)).

In smaller numbers, E-M81 men can be found in areas in contact with the Maghreb, both around the Sahara, in places like Sudan and Somalia (1.5%) and around the Mediterranean in places like Jordan (4.0%), Lebanon (1.9%), Turkey, Greece (1.8%) (Nea Nikomedeia and Sesklo/Dimini, King et al. (2008)) and amongst Sephardic Jews.

Sub-clades

There are two recognized sub-clades, although one is much more important than the other.

• E1b1b1b1 (E-M107). Underhill et al. (2000) found one example in Mali.
• E1b1b1b2 (E-M183). This clade is extremely dominant within E-M81. In fact, while Karafet et al. (2008) continues to describe this as a sub-clade of E-M81, and ISOGG defers to Karafet et al., all data seems to imply that it should actually be considered phylogenetically equivalent to M81. As of 21st June 2009, several SNPs are considered to define sub-clades of E-M183, although the phylogenetic structure is not yet known with confidence: M165, M310, and L19.