This article needs attention from an expert in Human Genetic History. The specific problem is: Nomenclature of haplogroup(s) and subclades.(November 2015)
|Possible time of origin||28–33,000 years ago|
|Possible place of origin||South-Eastern or Eastern Europe.|
|Highest frequencies||I2a1a: Sardinia |
Haplogroup I-M438, also known as I2 (ISOGG 2019), is a human DNA Y-chromosome haplogroup, a subclade of Haplogroup I-M170. Haplogroup I-M438 originated some time around 26,000–31,000 BCE. It originated in Europe and developed into several main subgroups : I2-M438*, I2a-L460, I2b-L415 and I2c-L596. The haplogroup can be found all over Europe and reaches its maximum frequency in the Dinaric Alps (Balkans) via founder effect. Examples of basal I-M438* have been found in males from Crete and Sicily .
Origin & prehistoric presence
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Haplogroup I2a was the most frequent Y-DNA among western European mesolithic hunter gatherers (WHG) belonging to Villabruna Cluster. A 2015 study found haplogroup I2a in 13,500 year old remains from the Azilian culture (from Grotte du Bichon, modern Switzerland). Subclades of I2a1 (I-P37.2), namely I-M423 and I-M26 have been found in remains of Western European Hunter-Gatherers dating from 10,000 to 8,000 years before present respectively.
In a 2015 study published in Nature, the remains of six individuals from Motala ascribed to the Kongemose culture were successfully analyzed. With regards to Y-DNA, two individuals were ascribed to haplogroup I2a1b, one individual was ascribed to haplogroup I2a1, and one individual was ascribed to haplogroup I2c.
Subclades of I-L460
The I-P37.2+, also known as I2a1a (ISOGG 2019) (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 version of I2 in Eastern Europe. The I2a is further made up by sub-groups I-M26, I-M423, I-L1286, I-L880.
Haplogroup I-M26 (or M26) I2a1a1a (ISOGG 2019).
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 North 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 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.
I2a1a2b-L621 is typical of the Slavic populations, being highest in Southeastern European regions of Bosnia-Herzegovina and South Croatia (>45%), in Bosniaks (43.53-52.17%), Croats (37.7-69.8%), and Serbs (36.6-42%), because of which is often called "Dinaric". It has the highest variance and also high concentration in Eastern Europe (Ukraine, Southeastern Poland, Belarus). According to YFull YTree it formed 11,400 YBP and had TMRCA 6,500 YBP, while its main subclades lineage is I-CTS10936 (6,500-5,600 YBP) > I-S19848 (5,600 YBP) > I-CTS4002 (5,600-5,100 YBP) > I-CTS10228 (5,100-3,400 YBP) > I-Y3120 (3,400-2,100 YBP) > I-Y18331 (2,100 YBP) / I-Z17855 (2,100-1650 YBP) / I-Y4460 (2,100 YBP) / I-S17250 (2,100-1,850 YBP) > I-PH908 (1,850-1,700 YBP).
Older research considered that the high frequency of this subclade in the South Slavic-speaking populations to be the result of "pre-Slavic" paleolithic settlement in the region. Peričić et al. (2005) for instance place its expansion to have occurred "not earlier than the YD to Holocene transition and not later than the early Neolithic". However the prehistoric autochthonous origin of the haplogroup I2 in the Balkans is now considered as out of date,[nb 1] as already Battaglia et al. (2009) observed highest variance of the haplogroup in Ukraine, and Zupan et al. (2013) noted that it suggests it arrived with Slavic migration from the homeland which was in present-day Ukraine. The research by O.M. Utevska (2017) concluded that the haplogroup STR haplotypes have the highest diversity in Ukraine, with ancestral STR marker result "DYS448=20" comprising "Dnieper-Carpathian" cluster, while younger derived result "DYS448=19" comprising the "Balkan cluster" which is predominant among the South Slavs. This "Balkan cluster" also has the highest variance in Ukraine, which indicates that the very high frequency in the Western Balkan is because of a founder effect. Utevska calculated that the STR cluster divergence and its secondary expansion from the middle reaches of the Dnieper river or from Eastern Carpathians towards the Balkan peninsula happened approximately 2,860 ± 730 years ago, relating it to the times before Slavs, but much after the decline of the Cucuteni–Trypillia culture. However, STR-based calculations give overestimated dates, and more specifically, the "Balkan cluster" is represented by a single SNP, I-PH908, known as I2a1a2b1a1a1c in ISOGG phylogenetic tree (2019), and according to YFull YTree it formed and had TMRCA approximately 1,850-1,700 YBP (2nd-3rd century AD).
It is considered that I-L621 could have been present in the Cucuteni–Trypillia culture, but until now was mainly found G2a and non-I2-L621 clades, and another clade I2a1a1-CTS595 was present in the Baden culture of the Chalcolithic Carpathian Basin. Although it is dominant among the modern Slavic peoples on the territory of the former Balkan provinces of the Roman Empire, until now it was not found among the samples from the Roman period and is almost absent in contemporary population of Italy. It was found in the skeletal remains with artifacts, indicating leaders, of Hungarian conquerors of the Carpathian Basin from the 9th century, part of Western Eurasian-Slavic component of the Hungarians. According to Pamjav et al. (2019) and Fóthi et al. (2020), the distribution of ancestral subclades like of I-CTS10228 among contemporary carriers indicates a rapid expansion from Southeastern Poland, is mainly related to the Slavs and their medieval migration, and the "largest demographic explosion occurred in the Balkans". The earliest archeogenetic sample until now is Sungir 6 (~900 YBP) near Vladimir, Russia which belonged to the I-S17250 > I-Y5596 > I-Z16971 > I-Y5595 > I-A16681 subclade, as well I-CTS10228 and I-Y3120 subclades were found in two Viking samples from Sweden (VK53) and Ukraine (VK542) with predominantly Slavic ancestry of which the second belongs to Gleb Svyatoslavich (11th century).
Haplogroup I-M223 aka I2a1b1 (ISOGG 2019), formerly I2a2a (ISOGG 2014). The age of YSTR variation for the I-M223 subclade has been variously estimated as 13.2±2.7 kya, 12.3±3.1 kya., 14.6 kya and 14.6±3.8 kya (Rootsi 2004). I-M223 has a peak in Germany and another in the northeast of Sweden, but also appears in Romania/Moldova, Russia, Greece, Italy and around the Black Sea. Haplogroup I-M223 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 I-M223 also occurs among approximately 1% of Sardinians.
Haplogroup I2a1b1a1a (ISOGG 2019) or I-M284, has been found almost exclusively amongst the populations of the United Kingdom and Ireland suggesting that it may have arisen amongst the Ancient Britons, with a most recent common ancestor (MRCA) who lived about 3,100 years BP. The presence of this subclade "provides some tentative evidence of ancient flow with eastern areas that could support the idea that the [late Celtic] La Tene culture was accompanied by some migration."
Where it is found in those of predominately Irish descent, with Gaelic surnames, it may suggest an ancestor who arrived in Ireland during prehistory, from Celtic Britain. For example, I-M284 includes many males with the surnames McGuinness and McCartan, who have a single, historically-recorded male ancestor in the 6th century; thus it is unlikely to be the result of subsequent migration from Britain to Ireland. Some subclades of I-M284 that are atypical of Ireland are relatively common in continental Europe, which also supports a point of origin east of Ireland.
Continentals. Mother Haplogroup for group I-Z161 (Continental 1 and 2) and I-L701 group (Continental 3). Around 10.000 years old.
Haplogroup I2a1b1a2b (ISOGG 2019). Z161+ defines the I2 Continental clade 1 and 2. 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.
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.
This section needs expansion. You can help by adding to it. (January 2021)
- The SNP I-P37 itself formed approximately 21,000 YBP and had TMRCA 18,400 YBP according to YFull YTree, being too old and widespread as an SNP for argumentation of ancient autochthony or medieval migration as well the old research used outdated nomenclature. According to "I-P37 (I2a)" project at Family Tree DNA, the divergence at STR marker DYS448 20 > 19 is reported since 2007, while the SNP which defines the STR Dinaric-South cluster, I-PH908, is reported since 2014. The SNP I-PH908 at ISOGG phylogenetic tree is named as I2a1a2b1a1a1c, while formed and had TMRCA approximately 1,800 YBP according to YFull.
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We looked at 16 loci from 640 I2a-L621 samples in FTDNA's I2a project database and found that 7 individuals were 2 genetic steps away the Karos samples, of whom 1 was a Hungarian from Kunszentmárton, 2 were Ukrainians, 1 was Lithuanian, 1 was Belarusian, 1 was Russian, and 1 was a German from Poland. Based on SNP analysis, the CTS10228 group is 2200 ± 300 years old. The group's demographic expansion may have begun in Southeast Poland around that time, as carriers of the oldest subgroup are found there today. The group cannot solely be tied to the Slavs, because the proto-Slavic period was later, around 300–500 CE ... The SNP-based age of the Eastern European CTS10228 branch is 2200 ± 300 years old. The carriers of the most ancient subgroup live in Southeast Poland, and it is likely that the rapid demographic expansion which brought the marker to other regions in Europe began there. The largest demographic explosion occurred in the Balkans, where the subgroup is dominant in 50.5% of Croatians, 30.1% of Serbs, 31.4% of Montenegrins, and in about 20% of Albanians and Greeks. As a result, this subgroup is often called Dinaric. It is interesting that while it is dominant among modern Balkan peoples, this subgroup has not been present yet during the Roman period, as it is almost absent in Italy as well (see Online Resource 5; ESM_5). ... Their genetic haplogroup, I2a-CTS10228, is widespread among Slavs, but it is only present in 7% of Caucasian peoples, namely among the Karachay ... As such, it appears that the I2a-CTS10228 haplogroup in the paternal lineage of the Karos leaders arises from a specific branch in the Northern Caucasus dating to about 400–500 CE. Its modern descendents live among the Karachay, Hungarians, and various other surrounding nationalities.
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Ken Nordtvedt has split I2a2-M423-Dinaric into Din-N and Din-S. Din-N is older than Din-S. N=north of the Danube and S=south of the Danube River ... May 8, 2007: Dinaric I1b1 and DYS 448. DYS448 19 for S and 20 for N.
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It is important to stress that the proposed old age of the I2a1b-M423 and R1a1a1b1a*-M558 lineages obtained in previous studies (Battaglia et al., 2009; Peričić et al., 2005; Rootsi et al., 2004; Underhill et al., 2007, 2015) has been based on STR analysis (8 and 10 loci, respectively) and recent studies clearly indicate that the STR-based age calculations tend to yield overestimated dates (Batini et al., 2015; Hallast et al., 2015; Karmin et al., 2015).
- Balanovsky O (May 2017). "Toward a consensus on SNP and STR mutation rates on the human Y-chromosome". Human Genetics. 136 (5): 575–590. doi:10.1007/s00439-017-1805-8. PMID 28455625. S2CID 3714493.
While the reasons for the difference between genealogical and evolutionary Y-STR rates are thus partly understood, it remains unclear which rate to use. Many have applied the evolutionary rate, though quite a few have used the genealogical, or both, rates. Genetic genealogists generally apply the genealogical rate and criticize population-genetic studies for reporting (in their view) three-times overestimated ages ... The age of each haplogroup was also calculated using the STR genealogical rate and the STR evolutionary rate. Confidence intervals for the two STR-based ages (not shown on the plot) do not overlap. For example, the genealogical age of I2a-L621 (2200 ± 500 years) reaches the envelope age (from 2600 to 3100 ages), while the evolutionary age lies far beyond (9900 ± 2700 years). The observed pattern (Fig. 2a) clearly differs for haplogroups of different age classes. For ages less than 7000 years, the genealogical STR rate provides results consistent with or slightly underestimating the "true" ages, while the evolutionary rate results in three-fold overestimates. For ages between roughly 7000 and 15,000 years neither STR rate provides correct results. For haplogroups older than 15,000 years, the evolutionary rate estimates correctly or overestimates the "true" age.
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Hg I2a1a2b-L621 was present in 5 Conqueror samples, and a 6th sample form Magyarhomorog (MH/9) most likely also belongs here, as MH/9 is a likely kin of MH/16 (see below). This Hg of European origin is most prominent in the Balkans and Eastern Europe, especially among Slavic speaking groups. It might have been a major lineage of the Cucuteni-Trypillian culture and it was present in the Baden culture of the Calcholitic Carpathian Basin24 ... The identical I2a1a2b Hg-s of Magyarhomorog individuals appears to be frequent among high-ranking Conquerors, as the most distinguished graves in the Karos2 and 3 cemeteries also belong to this lineage.
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It is notable that the European Y-Hg I2a1a2b1a1a was also specific for the Conqueror group, especially for the elite as also shown before,34 very often accompanied by Asian maternal lineages, indicating that I2a1a2b1a1a could be more typical for the immigrants than to the local population.
- Pamjav H, Fehér T, Németh E, Koppány Csáji L (2019). Genetika és őstörténet (in Hungarian). Napkút Kiadó. p. 58. ISBN 978-963-263-855-3.
Az I2-CTS10228 (köznevén „dinári-kárpáti") alcsoport legkorábbi közös őse 2200 évvel ezelőttre tehető, így esetében nem arról van szó, hogy a mezolit népesség Kelet-Európában ilyen mértékben fennmaradt volna, hanem arról, hogy egy, a mezolit csoportoktól származó szűk család az európai vaskorban sikeresen integrálódott egy olyan társadalomba, amely hamarosan erőteljes demográfiai expanzióba kezdett. Ez is mutatja, hogy nem feltétlenül népek, mintsem családok sikerével, nemzetségek elterjedésével is számolnunk kell, és ezt a jelenlegi etnikai identitással összefüggésbe hozni lehetetlen. A csoport elterjedése alapján valószínűsíthető, hogy a szláv népek migrációjában vett részt, így válva az R1a-t követően a második legdominánsabb csoporttá a mai Kelet-Európában. Nyugat-Európából viszont teljes mértékben hiányzik, kivéve a kora középkorban szláv nyelvet beszélő keletnémet területeket.
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