Haplogroup I (M170) is a

Y-chromosome DNA In human genetics, a human Y-chromosome DNA haplogroup is a haplogroup defined by specific mutations in the non- recombining portions of DNA on the male-specific Y chromosome (Y-DNA). Individuals within a haplogroup share similar numbers of ...

haplogroup. It is a subgroup of haplogroup IJ, which itself is a derivative of the haplogroup IJK. Subclades I1 and I2 can be found in most present-day European populations, with peaks in some

Northern Europe The northern region of Europe has several definitions. A restrictive definition may describe northern Europe as being roughly north of the southern coast of the Baltic Sea, which is about 54th parallel north, 54°N, or may be based on other ge ...

an and

Southeastern Europe Southeast Europe or Southeastern Europe is a geographical sub-region of Europe, consisting primarily of the region of the Balkans, as well as adjacent regions and Archipelago, archipelagos. There are overlapping and conflicting definitions of t ...

an countries. Haplogroup I most likely arose in Europe, with it so far found in Palaeolithic sites throughout Europe, but not outside it. It diverged from common ancestor IJ* about 43,000 years ago. Early evidence for haplogroup J has been found in the Caucasus and Iran. In addition, living examples of the precursor Haplogroup IJ* have been found only in Iran, among the Mazandarani and ethnic

Persians Persians ( ), or the Persian people (), are an Iranian ethnic group from West Asia that came from an earlier group called the Proto-Iranians, which likely split from the Indo-Iranians in 1800 BCE from either Afghanistan or Central Asia. They ...

from Fars. This may indicate that IJ originated in South West Asia. The oldest example found was originally that of Paglicci133 from

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

, which is at least 31,000 years old, however, in a later study this was changed, and instead Dolní Věstonice (DV14) from the

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

was reported as the oldest, being at least 30,800 years old. Haplogroup I has been found in multiple individuals belonging to the Gravettian culture. The

Gravettian The Gravettian is an archaeological industry of the European Upper Paleolithic that succeeded the Aurignacian circa 33,000 years BP. It is archaeologically the last European culture many consider unified, and had mostly disappeared by ...

s expanded westwards from the far corner of Eastern Europe, likely Russia, to Central Europe. They are associated with a genetic cluster that is normally called the Věstonice cluster.

Origins

Available evidence suggests that I-M170 was preceded into areas in which it would later become dominant by haplogroups K2a (K-M2308) and C1 (Haplogroup C-F3393). K2a and C1 have been found in the oldest sequenced male remains from Western Eurasia (dating from circa 45,000 to 35,000 years BP), such as: Ust'-Ishim man (modern west Siberia) K2a*, Oase 1 (Romania) K2a*, Kostenki 14 (south west Russia) C1b, and Goyet Q116-1 (Belgium) C1a. The oldest I-M170 found is that of an individual known as Krems WA3 (lower Austria), dating from circa 33,000-24,000 BP. At the same site, two twin boys were also found, both were assigned to haplogroup I*. Haplogroup IJ was in the

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

and/or

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

about 40,000 years ago. The TMRCA (time to

most recent common ancestor A most recent common ancestor (MRCA), also known as a last common ancestor (LCA), is the most recent individual from which all organisms of a set are inferred to have descended. The most recent common ancestor of a higher taxon is generally assu ...

) for I-M170 was estimated by Karafet and colleagues in 2008 to be 22,200 years ago, with a confidence interval between 15,300 and 30,000 years ago. This would make the founding event of I-M170 approximately contemporaneous with the

Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered m ...

(LGM), which lasted from 26,500 years ago until approximately 19,500 years ago. TMRCA is an estimate of the time of subclade divergence. Rootsi and colleagues in 2004 also note two other dates for a clade, age of STR variation, and time since population divergence. These last two dates are roughly associated, and occur somewhat after subclade divergence. For Haplogroup I-M170 they estimate time to STR variation as 24,000 ±7,100 years ago and time to population divergence as 23,000 ±7,700 years ago. These estimates are consistent with those of Karafet 2008 cited above. However, Underhill and his colleagues calculate the time to subclade divergence of I1 and I2 to be 28,400 ±5,100 years ago, although they calculate the STR variation age of I1 at only 8,100 ±1,500 years ago. Semino (2000) speculated that the initial dispersion of this population corresponds to the diffusion of the

culture. Later the haplogroup, along with two cases of Haplogroup C, was found in human remains belonging to the previously mentioned Gravettian culture and in individuals of the

Magdalenian Magdalenian cultures (also Madelenian; ) are later cultures of the Upper Paleolithic and Mesolithic in western Europe. They date from around 17,000 to 12,000 years before present. It is named after the type site of Abri de la Madeleine, a ro ...

and Azilian cultures. Rootsi and colleagues in 2004 suggested that each of the ancestral populations now dominated by a particular subclade of Haplogroup I-M170 experienced an independent population expansion immediately after the Last Glacial Maximum. The five known cases of Haplogroup I from

Upper Paleolithic The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age. Very broadly, it dates to between 50,000 and 12,000 years ago (the beginning of the Holocene), according to some theories ...

European human remains make it one of the most frequent haplogroup from that period. In 2016, the 31,210–34,580-year-old remains of a hunter-gatherer from Paglicci Cave, Apulia, Italy were found to carry I-M170. So far, only Haplogroup F* and Haplogroup C1b have been documented, once each, on older remains in Europe. I2 subclade of I-M170 is the main haplogroup found on male remains in

Mesolithic The Mesolithic (Ancient Greek language, Greek: μέσος, ''mesos'' 'middle' + λίθος, ''lithos'' 'stone') or Middle Stone Age is the Old World archaeological period between the Upper Paleolithic and the Neolithic. The term Epipaleolithic i ...

Europe, until circa 6,000 BCE, when

mass migration Mass migration refers to the migration of large groups of people from one geographical area to another. Mass migration is distinguished from individual or small-scale migration; and also from seasonal migration, which may occur on a regular basi ...

into Europe of Anatolian farmers carrying Y-DNA G2a happened. Due to the arrival of so-called Early European Farmers (EEFs), I-M170 is outnumbered by Haplogroup G among

Neolithic The Neolithic or New Stone Age (from Ancient Greek, Greek 'new' and 'stone') is an archaeological period, the final division of the Stone Age in Mesopotamia, Asia, Europe and Africa (c. 10,000 BCE to c. 2,000 BCE). It saw the Neolithic Revo ...

European remains and by Haplogroup R in later remains. The earliest documentation of I1 is from Neolithic Hungary, although it must have separated from I2 at an earlier point in time. In one instance, haplogroup I was found far from Europe, among 2,000-year-old remains from Mongolia. It would seem to be that separate waves of population movement impacted

. The role of the

Balkans The Balkans ( , ), corresponding partially with the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throug ...

as a long-standing corridor to Europe from

Anatolia Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

and/or the

Caucasus The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...

is shown by the common phylogenetic origins of both haplogroups I and J in the parent haplogroup IJ (M429). This common ancestry suggests that the subclades of IJ entered the Balkans from Anatolia or the Caucasus, some time before the Last Glacial Maximum. I and J were subsequently distributed in Asia and Europe in a disjunctive phylogeographic pattern typical of "sibling" haplogroups. A natural geographical corridor like the Balkans is likely to have been used later by members of other subclades of IJ, as well as other haplogroups, including those associated with Early European Farmers. The existence of Haplogroup IJK – the ancestor of both haplogroups IJ and K (M9) – and its evolutionary distance from other subclades of Haplogroup F (M89), supports the inference that haplogroups IJ and K both arose in Southwestern Asia. Living carriers of F* and IJ* have been reported from the

Iranian Plateau The Iranian plateau or Persian plateau is a geological feature spanning parts of the Caucasus, Central Asia, South Asia, and West Asia. It makes up part of the Eurasian plate, and is wedged between the Arabian plate and the Indian plate. ...

Distribution

Frequencies of Haplogroup I:

Subgroups

The subclades of Haplogroup I-M170 with their defining mutations, as of 2011.ISOGG 2011
/ref> Up-to-date phylogenetic trees listing all currently known subclades of I can be found a
Y-Full
an
FamilyTreeDNA
*I-M170 ( L41, M170, M258, P19_1, P19_2, P19_3, P19_4, P19_5, P38, P212, Page123, U179) ''Middle East, Caucasus, Europe.'' ** I-M253 Haplogroup I1 (L64, L75, L80, L81, L118, L121/S62, L123, L124/S64, L125/S65, L157, L186, L187, M253, M307.2/P203.2, M450/S109, P30, P40, S63, S66, S107, S108, S110, S111) ''Typical of populations of

Scandinavia Scandinavia is a subregion#Europe, subregion of northern Europe, with strong historical, cultural, and linguistic ties between its constituent peoples. ''Scandinavia'' most commonly refers to Denmark, Norway, and Sweden. It can sometimes also ...

and

Northwest Europe Northwestern Europe, or Northwest Europe, is a loosely defined subregion of Europe, overlapping Northern Europe, Northern and Western Europe. The term is used in geographic, history, and military contexts. Geographic definitions Geography, Geo ...

, with a moderate distribution throughout

Eastern Europe Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural and socio-economic connotations. Its eastern boundary is marked by the Ural Mountain ...

'' ''In

at 1%'' ***I1a DF29/S438 ****I1a1 CTS6364/Z2336 *****I1a1a M227 ******I1a1a1 M72 *****I1a1b L22/S142 ******I1a1b1 P109 ******I1a1b2 L205 ******I1a1b3 L287 *******I1a1b3a L258/S335 ********I1a1b3a1 L296 ******I1a1b4 L300/S241 ******I1a1b5 L813/Z719 ****I1a2 S244/Z58 *****I1a2a S246/Z59 ******I1a2a1 S337/Z60, S439/Z61, Z62 *******I1a2a1a Z140, Z141 ********I1a2a1a1 Z2535 *********I1a2a1a1a L338 ********I1a2a1a2 F2642 *******I1a2a1b Z73 *******I1a2a1c L573 *******I1a2a1d L1248 ********I1a2a1d1 L803 ******I1a2a2 Z382 *****I1a2b S296/Z138, Z139 ******I1a2b1 Z2541 ****I1a3 S243/Z63 *****I1a3a L1237 ***I1b Z131 ** I-M438 Haplogroup I2 L68/PF3781/S329, M438/P215/PF3853/S31 ***I2a L460/PF3647/S238 ****I2a1 P37.2 *****I2a1a L158/PF4073/S433, L159.1/S169.1, M26/PF4056 ******I2a1a1 L160/PF4013 *****I2a1b L178/S328, M423 ******I2a1b1 L161.1/S185 ******I2a1b2 L621/S392 *******I2a1b2a1a L147.2 *****I2a1c L233/S183 ****I2a2 L35/PF3862/S150, L37/PF6900/S153, L181, M436/P214/PF3856/S33, P216/PF3855/S30, P217/PF3854/S23, P218/S32 *****I2a2a L34/PF3857/S151, L36/S152, L59, L368, L622, M223, P219/PF3859/S24, P220/S119, P221/PF3858/S120, P222/PF3861/U250/S118, P223/PF3860/S117, Z77 ******I2a2a1 CTS616, CTS9183 *******I2a2a1a M284 ********I2a2a1a1 L1195 *********I2a2a1a1a L126/S165, L137/S166, L369 *********I2a2a1a1b L1193 *******I2a2a1b L701, L702 ********I2a2a1b1 P78 ********I2a2a1b2 L699, L703 *********I2a2a1b2a L704 *******I2a2a1c Z161 ********I2a2a1c1 L801/S390 *********I2a2a1c1a CTS1977 **********I2a2a1c1a1 P95 *********I2a2a1c1b CTS6433 **********I2a2a1c1b1 Z78 ***********I2a2a1c1b1a L1198 ************I2a2a1c1b1a1 Z190 *************I2a2a1c1b1a1a S434/Z79 ********I2a2a1c2 L623, L147.4 *******I2a2a1d L1229 ********I2a2a1d1 Z2054 *********I2a2a1d1a L812/S391 ********I2a2a1d2 L1230 ******I2a2a2 L1228 *****I2a2b L38/S154, L39/S155, L40/S156, L65.1/S159.1, L272.3 ******I2a2b1 L533 ***I2b L415, L416, L417 ***I2c L596/PF6907/S292, L597/S333 ''Note that the naming of some of the subgroups has changed, as new markers have been identified, and the sequence of mutations has become clearer.''

I-M170

The composite subclade I-M170 contains individuals directly descended from the earliest members of Haplogroup I, bearing none of the subsequent mutations which identify the remaining named subclades. Several I* individuals, who do not fall into any known subclades, have been found among the Lak people of

Dagestan Dagestan ( ; ; ), officially the Republic of Dagestan, is a republic of Russia situated in the North Caucasus of Eastern Europe, along the Caspian Sea. It is located north of the Greater Caucasus, and is a part of the North Caucasian Fede ...

, at a rate of (3/21), as well as Turkey (8/741),

Adygea Adygea ( ), officially the Republic of Adygea or the Adygean Republic, is a republics of Russia, republic of Russia. It is situated in the North Caucasus of Eastern Europe. The republic is a part of the Southern Federal District, and covers an a ...

in the Caucasus (2/138) and

Iraq Iraq, officially the Republic of Iraq, is a country in West Asia. It is bordered by Saudi Arabia to Iraq–Saudi Arabia border, the south, Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq border, the east, the Persian Gulf and ...

(1/176), even though I-M170 occurs at only very low frequencies among modern populations of these regions as a whole. This is consistent with the belief that the haplogroup first appeared in South West Eurasia. There are also high frequencies of Haplogroup I* among the

Andalusians The Andalusians () are the people of Andalusia, an autonomous community in southern Spain. Andalusia's statute of autonomy defines Andalusians as the Spanish citizens who reside in any of the municipalities of Andalusia, as well as those Spani ...

(3/103), French (4/179),

Slovenians The Slovenes, also known as Slovenians ( ), are a South Slavs, South Slavic ethnic group native to Slovenia and adjacent regions in Italy, Austria and Hungary. Slovenes share a common ancestry, Slovenian culture, culture, and History of Slove ...

(2/55), Tabassarans (1/30), and Saami (1/35). (Neither study from which the above figures were drawn excluded the present I2-M438 clade as a whole, but only certain subclades, so these presumed cases I* may possibly belong to I2.) A living Hazara male from Afghanistan has also been found to carry I*, with all known subclades of both I1 (M253) and I2 (M438) ruled out.

I1-M253

Haplogroup I1-M253 (M253, M307, P30, P40) displays a very clear frequency gradient, with a peak frequency of approximately 35% among the populations of southern Norway, southwestern Sweden, and Denmark, and rapidly decreasing frequencies toward the edges of the historically Germanic-influenced world. A notable exception is Finland, where frequency in West Finns is up to 40%, and in certain provinces like

Satakunta Satakunta (in both Finnish language, Finnish and Swedish language, Swedish, ; historically ''Satacundia'') is a Regions of Finland, region ( / ) of Finland, part of the former Western Finland Province. It borders the regions of Southwest Finland ...

more than 50%. I1 is believed to have become common as a result of a founder effect during the

Nordic Bronze Age The Nordic Bronze Age (also Northern Bronze Age, or Scandinavian Bronze Age) is a period of Scandinavian prehistory from . The Nordic Bronze Age culture emerged about 1750 BC as a continuation of the Late Neolithic Dagger period, which is root ...

, and subsequently spread throughout Europe during the

Migration Period The Migration Period ( 300 to 600 AD), also known as the Barbarian Invasions, was a period in European history marked by large-scale migrations that saw the fall of the Western Roman Empire and subsequent settlement of its former territories ...

when Germanic tribes migrated from southern

and northern

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

to other places in Europe. Outside

Fennoscandia __NOTOC__ Fennoscandia (Finnish language, Finnish, Swedish language, Swedish and ; ), or the Fennoscandian Peninsula, is a peninsula in Europe which includes the Scandinavian Peninsula, Scandinavian and Kola Peninsula, Kola peninsulas, mainland ...

, distribution of Haplogroup I1-M253 is closely correlated with that of Haplogroup I2a2-M436; but among Scandinavians (including both Germanic and Uralic peoples of the region) nearly all the Haplogroup I-M170 Y-chromosomes are I1-M253. Another characteristic of the Scandinavian I1-M253 Y-chromosomes is their rather low

haplotype A haplotype (haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. Many organisms contain genetic material (DNA) which is inherited from two parents. Normally these organisms have their DNA orga ...

diversity (STR diversity): a greater variety of Haplogroup I1-M253 Y-chromosomes has been found among the French and

Italians Italians (, ) are a European peoples, European ethnic group native to the Italian geographical region. Italians share a common Italian culture, culture, History of Italy, history, Cultural heritage, ancestry and Italian language, language. ...

, despite the much lower overall frequency of Haplogroup I1-M253 among the modern French and Italian populations. This, along with the structure of the phylogenetic tree of I1-M253 strongly suggests that most living I1 males are the descendants of an initially small group of reproductively successful men who lived in Scandinavia during the Nordic Bronze Age.

I2-M438

Haplogroup I2-M438, previously I1b, may have originated in southern Europe – it is now found at its highest frequencies in the western

and

Sardinia Sardinia ( ; ; ) is the Mediterranean islands#By area, second-largest island in the Mediterranean Sea, after Sicily, and one of the Regions of Italy, twenty regions of Italy. It is located west of the Italian Peninsula, north of Tunisia an ...

– some 15,000–17,000 years ago and developed into three main subgroups : I2-M438*, I2a-L460, I2b-L415 and I2c-L596.

I2a1a-M26

Haplogroup I2a1a-M26 is notable for its strong presence in Sardinia. Haplogroup I-M170 comprises approximately 40% of all patrilines among the Sardinians, and I2a1a-M26 is the predominant type of I among them. Haplogroup I2a1a-M26 is practically absent east of France and Italy, while it is found at low but significant frequencies outside of Sardinia in the

Balearic Islands The Balearic Islands are an archipelago in the western Mediterranean Sea, near the eastern coast of the Iberian Peninsula. The archipelago forms a Provinces of Spain, province and Autonomous communities of Spain, autonomous community of Spain, ...

, Castile-León, the Basque Country, the

Pyrenees The Pyrenees are a mountain range straddling the border of France and Spain. They extend nearly from their union with the Cantabrian Mountains to Cap de Creus on the Mediterranean coast, reaching a maximum elevation of at the peak of Aneto. ...

, southern and western France, and parts of the

Maghreb The Maghreb (; ), also known as the Arab Maghreb () and Northwest Africa, is the western part of the Arab world. The region comprises western and central North Africa, including Algeria, Libya, Mauritania, Morocco, and Tunisia. The Maghreb al ...

in North Africa, Great Britain, and Ireland. Haplogroup I2a1a-M26 appears to be the only subclade of Haplogroup I-M170 found among the

Basques The Basques ( or ; ; ; ) are a Southwestern European ethnic group, characterised by the Basque language, a Basque culture, common culture and shared genetic ancestry to the ancient Vascones and Aquitanians. Basques are indigenous peoples, ...

, but appears to be found at somewhat higher frequencies among the general populations of Castile-León in Spain and

Béarn Béarn (; ; or ''Biarn''; or ''Biarno''; or ''Bearnia'') is one of the traditional provinces of France, located in the Pyrenees mountains and in the plain at their feet, in Southwestern France. Along with the three Northern Basque Country, ...

in France than among the population of ethnic Basques. The M26 mutation is found in native males inhabiting every geographic region where megaliths may be found, including such far-flung and culturally disconnected regions as the Canary Islands, the Balearic Isles, Corsica, Ireland, and Sweden. The distribution of I2a1a-M26 also mirrors that of the Atlantic Bronze Age cultures, which indicates a potential spread via the

obsidian Obsidian ( ) is a naturally occurring volcanic glass formed when lava extrusive rock, extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Produced from felsic lava, obsidian is rich in the lighter element ...

trade or a regular maritime exchange of some of metallurgical products.

I2a1b-M423

The approximate frequency and variance of haplogroup I-P37 clusters in Eastern Europe

Haplogroup I2a1b-M423 is the most frequent Y-chromosome haplogroup I-M170 in Central and Eastern European populations, reaching its peak in the Western Balkans, most notably in

Dalmatia Dalmatia (; ; ) is a historical region located in modern-day Croatia and Montenegro, on the eastern shore of the Adriatic Sea. Through time it formed part of several historical states, most notably the Roman Empire, the Kingdom of Croatia (925 ...

(50–60%) and

Bosnia-Herzegovina Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to the north a ...

(up to 71%, avg. 40-50%). Its subclade I-L161 has greater variance in Ireland and Great Britain, but overall frequency is very low (2–3%), while subclade I-L162 has the highest variance and also high concentration in Eastern Europe (Ukraine, Southeastern Poland, Belarus).

I2a2-M436

The distribution of Haplogroup I2a2-M436 (M436/P214/S33, P216/S30, P217/S23, P218/S32) is closely correlated to that of Haplogroup I1 except in

, which suggests that it was probably harbored by at least one of the Paleolithic refuge populations that also harbored Haplogroup I1-M253; the lack of correlation between the distributions of I1-M253 and I2a2-M436 in Fennoscandia may be a result of Haplogroup I2a2-M436's being more strongly affected in the earliest settlement of this region by

founder effect In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, us ...

s and

genetic drift Genetic drift, also known as random genetic drift, allelic drift or the Wright effect, is the change in the Allele frequency, frequency of an existing gene variant (allele) in a population due to random chance. Genetic drift may cause gene va ...

due to its rarity, as Haplogroup I2a2-M436 comprises less than 10% of the total Y-chromosome diversity of all populations outside of

Lower Saxony Lower Saxony is a States of Germany, German state (') in Northern Germany, northwestern Germany. It is the second-largest state by land area, with , and fourth-largest in population (8 million in 2021) among the 16 ' of the Germany, Federal Re ...

. Haplogroup I2a2-M436 has been found in over 4% of the population only in Germany, the Netherlands, Belgium, Denmark, England (not including

Cornwall Cornwall (; or ) is a Ceremonial counties of England, ceremonial county in South West England. It is also one of the Celtic nations and the homeland of the Cornish people. The county is bordered by the Atlantic Ocean to the north and west, ...

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

, and the southern tips of Sweden and Norway in Northwest Europe; the provinces of

Normandy Normandy (; or ) is a geographical and cultural region in northwestern Europe, roughly coextensive with the historical Duchy of Normandy. Normandy comprises Normandy (administrative region), mainland Normandy (a part of France) and insular N ...

Maine Maine ( ) is a U.S. state, state in the New England region of the United States, and the northeasternmost state in the Contiguous United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Provinces and ...

, Anjou, and Perche in northwestern France; the province of

Provence Provence is a geographical region and historical province of southeastern France, which stretches from the left bank of the lower Rhône to the west to the France–Italy border, Italian border to the east; it is bordered by the Mediterrane ...

in southeastern France; the regions of

Tuscany Tuscany ( ; ) is a Regions of Italy, region in central Italy with an area of about and a population of 3,660,834 inhabitants as of 2025. The capital city is Florence. Tuscany is known for its landscapes, history, artistic legacy, and its in ...

Umbria Umbria ( ; ) is a Regions of Italy, region of central Italy. It includes Lake Trasimeno and Cascata delle Marmore, Marmore Falls, and is crossed by the Tiber. It is the only landlocked region on the Italian Peninsula, Apennine Peninsula. The re ...

, and

Latium Latium ( , ; ) is the region of central western Italy in which the city of Rome was founded and grew to be the capital city of the Roman Empire. Definition Latium was originally a small triangle of fertile, volcanic soil (Old Latium) on whic ...

in Italy; and

Moldavia Moldavia (, or ; in Romanian Cyrillic alphabet, Romanian Cyrillic: or ) is a historical region and former principality in Eastern Europe, corresponding to the territory between the Eastern Carpathians and the Dniester River. An initially in ...

and the area around Russia's

Ryazan Oblast Ryazan Oblast (, ) is a federal subjects of Russia, federal subject of Russia (an oblast). Its administrative center is the types of inhabited localities in Russia, city of Ryazan, which is also the oblast's largest city. Geography Ryazan Oblast ...

and Republic of Mordovia in Eastern Europe. One subclade of Haplogroup I2a2-M436, namely I2a2a1a1-M284, has been found almost exclusively among the population of Great Britain, which has been taken to suggest that the clade may have a very long history in that island. It is notable, however, that the distributions of Haplogroup I1-M253 and Haplogroup I2a2-M436 seem to correlate fairly well with the extent of historical influence of

Germanic peoples The Germanic peoples were tribal groups who lived in Northern Europe in Classical antiquity and the Early Middle Ages. In modern scholarship, they typically include not only the Roman-era ''Germani'' who lived in both ''Germania'' and parts of ...

. The punctual presence of both haplogroups at a low frequency in the area of the historical regions of

Bithynia Bithynia (; ) was an ancient region, kingdom and Roman province in the northwest of Asia Minor (present-day Turkey), adjoining the Sea of Marmara, the Bosporus, and the Black Sea. It bordered Mysia to the southwest, Paphlagonia to the northeast a ...

and

Galatia Galatia (; , ''Galatía'') was an ancient area in the highlands of central Anatolia, roughly corresponding to the provinces of Ankara and Eskişehir in modern Turkey. Galatia was named after the Gauls from Thrace (cf. Tylis), who settled here ...

in Turkey may be related to the

Varangian Guard The Varangian Guard () was an elite unit of the Byzantine army from the tenth to the fourteenth century who served as personal bodyguards to the Byzantine emperors. The Varangian Guard was known for being primarily composed of recruits from Nort ...

or rather suggests a connection with the ancient

Gauls The Gauls (; , ''Galátai'') were a group of Celts, Celtic peoples of mainland Europe in the Iron Age Europe, Iron Age and the Roman Gaul, Roman period (roughly 5th century BC to 5th century AD). Their homeland was known as Gaul (''Gallia''). Th ...

Thrace Thrace (, ; ; ; ) is a geographical and historical region in Southeast Europe roughly corresponding to the province of Thrace in the Roman Empire. Bounded by the Balkan Mountains to the north, the Aegean Sea to the south, and the Black Se ...

, several tribes of which are recorded to have immigrated to those parts of Anatolia at the invitation of

Nicomedes I of Bithynia Nicomedes I (; lived c. 300 BC – c. 255 BC, reigned 278 BC – c. 255 BC), second king of Bithynia, was the eldest son of Zipoetes I, whom he succeeded on the throne in 278 BC. Life He began his reign by killing two of his brothers, but ...

. This suggestion is supported by recent genetic studies regarding Y-DNA Haplogroup I2b2-L38 have concluded that there was some Late Iron Age migration of Celtic La Tène people, through Belgium, to the British Isles including north-east Ireland. Haplogroup I2a2-M436 also occurs among approximately 1% of Sardinians, and in

Hazaras The Hazaras (; ) are an ethnic group and a principal component of Afghanistan’s population. They are one of the largest ethnic groups in Afghanistan, primarily residing in the Hazaristan (Hazarajat) region in central Afghanistan. Hazaras al ...

from Afghanistan at 3%.

Specifications of mutation

The technical details of U179 are: :Nucleotide change (rs2319818): G to A :Position (base pair): 275 :Total size (base pairs): 220 :Forward 5′→ 3′: :Reverse 5′→ 3′:

Height

Although

height Height is measure of vertical distance, either vertical extent (how "tall" something or someone is) or vertical position (how "high" a point is). For an example of vertical extent, "This basketball player is 7 foot 1 inches in height." For an e ...

as a quantitative

autosomal An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal (sex chromosome) pairs, which may have different structures. The DNA in autosome ...

trait is not genetically related to Y-DNA haplogroups, it may be associated with unusually tall males, since those in the

Dinaric Alps The Dinaric Alps (), also Dinarides, are a mountain range in Southern Europe, Southern and Southcentral Europe, separating the continental Balkan Peninsula from the Adriatic Sea. They stretch from Italy in the northwest through Slovenia, Croatia ...

have been reported to be the tallest in the world, with an average male height of the range – in the cantons of

Bosnia Bosnia and Herzegovina, sometimes known as Bosnia-Herzegovina and informally as Bosnia, is a country in Southeast Europe. Situated on the Balkans, Balkan Peninsula, it borders Serbia to the east, Montenegro to the southeast, and Croatia to th ...

, in

Sarajevo Sarajevo ( ), ; ''see Names of European cities in different languages (Q–T)#S, names in other languages'' is the Capital city, capital and List of cities in Bosnia and Herzegovina, largest city of Bosnia and Herzegovina, with a population of 2 ...

, – in the cantons of

Herzegovina Herzegovina ( or ; sh-Latn-Cyrl, Hercegovina, separator=" / ", Херцеговина, ) is the southern and smaller of two main geographical Regions of Bosnia and Herzegovina, regions of Bosnia and Herzegovina, the other being Bosnia (reg ...

mostly populated by

Croats The Croats (; , ) are a South Slavs, South Slavic ethnic group native to Croatia, Bosnia and Herzegovina and other neighboring countries in Central Europe, Central and Southeastern Europe who share a common Croatian Cultural heritage, ancest ...

. A 2014 study examining the correlation between Y-DNA haplogroups and height found a correlation between the haplogroups I1, R1b-U106, I2a1b-M423 and tall males.

Notes

* *Bennett, E.A., Prat, S., Péan, S., Crépin, L., Yanevich, A., Puaud, S., ... & Geigl, E. M. (2019)
The origin of the Gravettians: genomic evidence from a 36,000-year-old Eastern European
BioRxiv, 685404. * *The Genographic Project, National Geographic

*ISOGG

References

External links

Phylogenetic tree and distribution maps

from the International Society of Genetic Genealogy (ISOGG)of 2013
Phylogeography of Y-Chromosome Haplogroup IFrequency Distributions of Y-DNA Haplogroup I and its subclades – with Video TutorialFrequency and Variance of I1b
(now considered I2a2-M26)
Map of 'I1a'
(now considered I-M253)
Map of 'I1b'
(now considered I2a-P37.2)
Map of 'I1c'
(now considered I2b-M223)
Rescalled Haplogroup I Tree (K. Nordtvedt 2011).

Projects

I Project at FTDNAI1 Project at FTDNAI2* Project at FTDNAI2a project at FTDNAI2b project at FTDNAI2b2 L38+ project at FTDNAThe Scandinavian yDNA Genealogical Project at FTDNAThe Finland Genealogical Project at FTDNA

Other

Study of Y-Haplogroup I and Modal HaplotypesThe Y Chromosome Consortium (YCC)
*[http://members.bex.net/jtcullen515/haplotest.htm Haplo-I Subclade Predictor]
Spread of Haplogroup I
from ''National Geographic (magazine), National Geographic'' *Lichtenstein Cave#Ancient DNA Tests, I2b2 Y-DNA found in Bronze Age skeletons of Lichtenstein Cave
Haplogroup I-L38 (I2b2) ''In Search of the Origin of I-L38 (aka I2b2)''
{{DEFAULTSORT:Haplogroup I (Y-Dna) Human Y-DNA haplogroups, I