Haplogroup I M438

Origin and prehistoric presence

Haplogroup I2a may be the haplogroup of the first anatomically modern humans to inhabit Europe, Cro-Magnon. A 2015 study found Y DNA haplogroup I2a in a 13,000 year old, purportedly Cro-Magnon, fossil, of the Azilian culture from Bichon Switzerland The subclades of I-P37.2 - I-M423 and I-M26 were found on remains dated to 10,000 and 8,000 ybp respectively.

Sub-haplogroups

Haplogroup I is divided into I1 and I2. Sub-haplogroup I2 is further divided into I2a, I2b and I2c (ISOGG 2016). Further division is made up by SNPs (or Snips), Single Nucleotide Polymorphisms.

I-P37.2

The I-P37.2+ (or P37.2, L68) is the SNP that defines I2a1. The subclade divergence for I-P37.2 occurred 10.7±4.8 kya. The age of YSTR variation for the P37.2 subclade is 8.0±4.0 kya. It is the predominant Y-DNA lineage in Eastern Europe. The I2a is further made up by sub-groups I-M26, I-M423, I-L1286, I-L880.

I-L158

Haplogroup I-M26 (or M26) has previously and is still sometimes called Eu-8, I1b2 (YCC), I1b1a, I2a1 or I2a2.

Haplogroup I-L158 (L158, L159.1/S169.1, M26) accounts for approximately 40% of all patrilines among the Sardinians. It is also found at low to moderate frequency among populations of the Pyrenees (9.5% in Bortzerriak, Navarra; 9.7% in Chazetania, Aragon; 8% in Val d'Aran, Catalunya; 2.9% in Alt Urgell, Catalunya; and 8.1% in Baixa Cerdanya, Catalunya) and Iberia, and it has been found in 1.6% of a sample of Albanians living in the Republic of Macedonia and 1.2% (3/257) of a sample of Czechs. The age of YSTR variation for the M26 subclade has been calculated at 8.0±4.0 kya.

I-L178

I-L178 is very rare, but has been found in two persons from Germany and one from Poland. The age of YSTR variation for the M423 subclade is 8.8±3.6 kya.

I-L621

I-L621 is typical of the South Slavic populations of south-eastern Europe, being highest in Bosnia-Herzegovina (>50%) in Croats. There is also a high concentration of I-L621 in north-east Romania and Moldova. Several groups have determined the common occurrence of this subclade in the South Slavic-speaking populations to be the result of "pre-Slavic" paleolithic settlement in the region. Peričić et al. for instance places its expansion to have occurred "not earlier than the YD to Holocene transition and not later than the early Neolithic”. Decidedly, the Slavic population can be divided into two genetically distinct groups: one encompassing all Western-Slavic (Poles, Czechs, Slovaks, etc.), Eastern-Slavic (Russians, Ukrainians, Belarusians, etc.) and a few Southern-Slavic populations (north-western Croats and Slovenes), characterized by Haplogroup R1a, and one encompassing all remaining Southern Slavs (Serbs, Bosniaks, southern Croats, Montenegrins, Macedonians and Bulgarians) but also the non-Slavic Romanians, characterized by Haplogroup I2a1b2 (I-L621). According to Rebała et al., this phenomenon is explained by "contribution to the Y chromosomes of peoples who settled in the Balkan region before the Slavic expansion to the genetic heritage of Southern Slavs. It is attributed to the Cucuteni-Trypillian culture in what is now modern day Ukraine, Romania and Moldova. L69/S163 - Removed from I in 2011 and IJK in 2012.

I-M223

Haplogroup I2a2a (ISOGG 2014). The age of YSTR variation for the I-M223 subclade is 13.2±2.7 kya and 12.3±3.1 kya. I-M223 has a peak in Germany and another in eastern Sweden, but also appears in Romania/Moldova, Russia, Greece, Italy and around the Black Sea. Haplogroup I2a2a has been found in over 4% of the population only in Germany, the Netherlands, Belgium, Denmark, Scotland, and England (excluding Cornwall) -- also the southern tips of Sweden and Norway in Northwest Europe; the provinces of Normandy, Maine, Anjou, and Perche in northwestern France; the province of Provence in southeastern France; the regions of Tuscany, Umbria, and Latium in Italy; Moldavia and the area around Russia's Ryazan Oblast and Mordovia in Eastern Europe. Of historical note, both haplogroups I-M253 and I-M223 appear at a low frequency in the historical regions of Bithynia and Galatia in Turkey. Haplogroup I2a2a also occurs among approximately 1% of Sardinians. The subclade divergence for M223 occurred 14.6±3.8 kya (Rootsi 2004).

Haplogroup I-M223 can be further subdivided in several subclades designated in the Y2012 ISOGG tree as follows:

I-M284

Haplogroup I2a2a1a1 (ISOGG 2014). I-M284 has been found almost exclusively among the population of Great Britain, suggesting that the clade may have arisen in that island. I-M284 is comparatively rare in Ireland except in the north-east. In regard to north-east Ireland, the presence of this subclade "provides some tentative evidence of ancient flow with eastern areas that could support the idea that the La Tene culture was accompanied by some migration." Where it is found in those of Irish descent with Gaelic surnames, this suggests an ancestor who arrived in Ireland from Celtic Britain. Men with several Gaelic surnames such as McGuinness and McCartan bear this subclade, family groups that have a historically recorded 6th-century common ancestor, thus it is not the result of known recent gene flow between Britain and Ireland. While subclades of I-M284 are atypical of Ireland they are relatively common in continental Europe. The observed mutational divergence between men with this subclade suggests its foundation very approximately at 300 BC, thus dates and geography are circumstantially but not securely associated with Iron Age continental Europe.

I-CTS10057

Continentals. Mother Haplogroup for group I-Z161 (Continental 1 and 2) and I-L701 group (Continental 3). Around 10.000 years old.

I-Z161

Haplogroup I2a2a1b2 (ISOGG 2014). Z161+ defines the I2 Continental clade (except Continental 3). Its age is estimated around 7,000 years old. It is mainly found in North Europe, especially in Denmark, Germany, the Netherlands, and England. In Northwest Sicily it can also be found; this is believed to be due to remnants of a Norman settlement.

I-L701

Called Continental 3. Continental 3 has a wide distribution. Found in Central Europe from Germany, Austria to Poland, Romania and Ukraine, but also in lower frequencies in Greece, Italy, France, Spain, England, Ireland, and Armenia. It may have been disseminated in part by the Goths. It is nearly absent from Scandinavia and Scotland.