Haplogroup G

Haplogroup G (M201) is a branch of Haplogroup F (M89). Haplogroup G has an overall low frequency in most populations but is widely distributed within many ethnic groups of the Old World in Europe (especially in alpine regions), Caucasus, South Asia, western and central Asia, and northern Africa.

Various estimated dates and locations have been proposed for the origin of Haplogroup G. The National Geographic Society places haplogroup G origins in the Middle East 30,000 years ago and presumes that people carrying the haplogroup took part in the spread of the Neolithic.

Two scholarly papers have also suggested an origin in the Middle East, while differing on the date. Semino et al. (2000) suggested 17,000 years ago. Cinnioglu et al. (2004) suggested the mutation took place only 9,500 years ago.

Haplogroup G1 has an extremely low frequency in almost all countries except Iran and the countries adjoining Iran on the west. The highest reported concentration of G1 and its subgroups in a single country is in Iran, with next most frequent concentrations in neighboring countries to the west. There are distinctive Ashkenazi Jewish and Kazakh subgroups based on STR marker value combinations.

Haplogroup G2a (SNP P15+) has been identified in neolithic human remains in Europe dating between 5000-3000BC. Furthermore, the majority of all the male skeletons from the European Neolithic period have so far yielded Y-DNA belonging to this haplogroup.

The oldest skeletons confirmed by ancient DNA testing as carrying haplogroup G2a were five found in the Avellaner cave burial site for farmers in northeastern Spain and were dated by radiocarbon dating to about 7000 years ago. At the Neolithic cemetery of Derenburg Meerenstieg II, north central Germany, with burial artifacts belonging to the Linear Pottery culture, known in German as Linearbandkeramik (LBK).

G2a was found also in 20 out of 22 samples of ancient Y-DNA from Treilles, the type-site of a Late Neolithic group of farmers in the South of France, dated to about 5000 years ago.

Men who belong to G2 (P287+), but are negative for all G2 subgroups, represent a small number of haplogroup G men. P287 was identified at the University of Arizona and became widely known in late 2007. Its identification caused considerable renaming of G categories.

Haplogroup G men who belong to G2a (P15+), but are negative for all G2a subgroups, are uncommon in Europe but may represent a sizeable group in so far poorly tested areas east of Turkey.

Haplogroup G2a1 and its subgroups represent the majority of haplogroup G samples in some parts of the Caucasus Mountains area. They are found only in tiny numbers elsewhere.

The North Ossetians in the mid northern Caucasus area of Russia belong overwhelmingly to the G2a1 subgroup based on available samples. The South Ossetians and Svans generally south of North Ossetia have significant number of G2a1 persons, but population percentages have not yet been provided.

G2a1a and its one subgroup represent the majority of haplogroup G samples in some parts of the Caucasus Mountains area. G2a1a is found only in tiny numbers elsewhere.

The exceptionally high level of G2a1a in the North Ossetians has attracted attention and speculation. If a concentration of G2a1a points to the location of its origin, the north and south Caucasus region would be the likely location of origin. However, the first ancestors who were G2a1a could have been small in number, and a relocation from elsewhere is possible.

The most important factor in determining G2a1a origins is knowing from where the North Ossetians came. Because of the confederation nature of the Alans, it is possible the Ossetian ancestors were part of those Alans who did not participate in the Great Migration.

But it also seems plausible that the pre-Alan ancestors of the North Ossetians arrived there from south of the Caucasus where G is found in significant numbers and with the diversity seen in a longtime presence. The G in the area to the north of the Caucasus lacks both features. Two studies published in 2011 and one in 2012 argued that persons of the Caucasus had their origin in lands to the south.

Ashkenazi Jewish G2a1a men with northeastern European ancestry form a distinct cluster based on STR marker values. Men from the Caucasus and men from eastern Europe also form distinctive STR clusters.

The fourth site also from the same period is the Ötztal of the Italian Alps where the mummified remains of Ötzi the Iceman were discovered. Preliminary word is that the Iceman belongs to haplogroup G2a2b.

Haplogroup G2a2b is a rare group today in Europe. The authors of the Spanish study indicated that the Avellaner men had rare marker values in testing of their short tandem repeat (STR) markers.

This skeleton could not be dated by radiocarbon dating, but other skeletons there were dated to between 5,100 and 6,100 years old. The most detailed SNP mutation identified was S126 (L30), which defines G2a3.

The G2a2a subgroup (M286) is tiny. Samples indicating British Isles, Turkish and Lebanese ancestry have been identified. G2a2b would seem to encompass a significant group of G persons, and is found so far in scattered parts of Europe and North Africa and in Armenia.

Men who belong to G2a3, but are negative for all its subgroups, represent a small number today. This haplogroup was found in a Neolithic skeleton from around 5000 BC, in the cemetery of Derenburg Meerenstieg II, Germany, which forms part of the Linear Pottery culture, known in German as Linearbandkeramik (LBK), but was not tested for G2a3 subgroups.

G2a3a and its several subgroups seem most commonly found in Turkey and the coastal areas of the eastern Mediterranean where it can constitute up to 50% of haplogroup G samples. G2a3a is more common in southern Europe than northern Europe. In Europe, except in Italy, G2a3a constitutes less than 20% of G samples. G2a3a so far has seldom surfaced in northern Africa or southern Asia, but represents a small percentage of the G population in the Caucasus Mountains region and in Iran.

Haplogroup G2a3a seems most common in Turkey and Greece. Secondary concentrations of G2a3a are found in the northern and eastern Mediterranean, and it is found in very small numbers in more inland areas of Europe, the Middle East, Iran and the southern Caucasus Mountains area.

Research studies have not addressed the age of G2a3a. Based on available 67-marker STR samples, it would seem that the mutation that defines G2a3a arose perhaps about 4,000 years ago.

Perhaps about 5% of men in Turkey are G2a3a, the highest percentage of the general population in any country yet sampled. This 5% figure is based on the finding of the value of 21 at STR marker DYS390 in 21 of 57 G samples from throughout Turkey.

Among G persons, the 21 value is seen overwhelmingly in G2a3a persons. But values other than 21 occur to a small extent in G2a3a persons. So the total G2a3a percentage within Turkish G is likely close to 50 percent, and the 57 SNP-confirmed G samples represent 11% of 523 Turkish samples obtained in the largest study yet conducted of Turkish population genetics.

In adjacent Greece, SNP testing determined that half of eight G samples were G2a3a. The G samples represented 5% of 171 Greek samples. In contrast in nearby Crete, G2a3a was only 20% of the 21 G samples, with G samples representing 11% of 193 island samples.

Though treated separately in this study, Crete is part of Greece but with a different settlement history. Farther out in the Mediterranean, in a smaller sample size from Cyprus 4 of 7 G samples have the distinctive 21 value seen overwhelmingly in G2a3a persons.

Just to the south of Turkey among the Kurds of Iraq 7 of 14 likely G STR samples in the YHRD database have the value of 21 at DYS390 suggesting half the G population there belongs to G2a3a. This relatively high percentage of G2a3a is confined to the country’s northern Kurdish region.

Lebanon, Jordan and Palestine also have significant G2a3a populations though small sample sizes make broad conclusions difficult. In one study, 4 of 5 Palestinian G samples have the distinctive DYS390=21 value.

In Lebanon, at least 10 of 37 G samples have G2a3a features and are found among all the major religions there. In Jordan, 7 of 15 available G samples have 21 at marker DYS390. None of the G samples among the Druze peoples in these locations have STR marker values typical of G2a3a persons. In Syria, G2a3a seems less common than in the countries closer to the Mediterranean. Only 3 of 17 G samples there have the 21 value discussed.

It is logical that G2a3a spread westward along the Mediterranean from the area where it is most concentrated today (Turkey and the eastern Mediterranean countries) in conjunction with the trading, slave-selling and other migratory events originating in these lands. The first great trading empire that joined both ends of the Mediterranean was the Phoenician that originated in the Israel-Lebanon-Jordan area. After the demise of the Phoenicians, the Greeks, Romans, Byzantines and some “barbarians” could have spread G2a3a from the eastern Mediterranean to the west.

In comparisons of 67-marker G2a3a STR samples available from inland Europe with similar samples from (1) Turkey (2) Lebanon-Jordan and (3) Armenia certain deductions can be made. Most G2a3a Europeans have Armenians as their nearest relatives. Based on the number of mutations observed, some of these probably share common male ancestors as recently as the Dark Ages. Only one European showed Jordan/Lebanon samples as the nearest G relatives. Likewise none of the Europeans showed Turks alone as nearest relatives, but rather some European samples had Turks and Armenians equally related.

The sharing of common ancestors much farther back in time (perhaps 3,500 years ago) among some of these samples does not provide information so useful because the migration westward could have occurred anytime in the earlier period. The finding of likely G2a3a samples in the ancient isolated highlands of Sardinia, however, suggests the arrival of G2a3a in that island prior to the arrival of the Phoenicians. The latter began a Sardinian coastal presence about 3,000 years ago.

Samples from persons with British Isles, Sicilian and Turkish ancestry have been identified belonging to G2a3b.

The G2a3b1 definable subgroups are heavily concentrated throughout Europe west of the Black Sea and Russia where G2a3b1 is often in the majority among G persons. Small percentages of G2a3b1 are found primarily in the area encompassed by Turkey, the Caucasus countries, Iran and the Middle East where the G2a3b1 SNP may have originated. G2a3b1 is also found in India. The great majority of P303+ men belong to one of its subgroups.

The largest G2a3b1 subgroup based on available samples is one in which almost all persons have the value of 13 at STR marker DYS388. The L497 SNP (G2a3b1a2) encompasses these men, but most men L497 men belong to its subgroup Z725. There are additional subgroups of DYS388=13 men characterized by the presence of specific SNPs or uncommon STR marker oddities.

The next largest G2a3b1 subgroup is characterized by the presence of the U1 mutation (G2a3b1a1) But a high percentage of U1+ men belong to its two subgroups, L13/S13 (G2a3b1a1a)and Z1266 (G2a3b1a1b). The L13 subgroup is most common in north central Europe, and Z1266 is most common in the western Caucasus Mountains.

The final major subgroup is characterized by presence of the Z1903 SNP and so far by the value of 9 at marker DYS568. A high percentage of Z1903+ men belong to its subgroup, Z724. The Z724 subgroup contains a further large subgroup consisting overwhelmingly of Ashkenazi Jews.

The highest percentage of G2a3b1 persons in a discrete population so far described is on the island of Ibiza off the eastern Spanish coast.

This G2a3b2 group is certainly smaller in numbers of men included than G2a3b1, but only a small amount of testing has occurred for the L177 mutations. So far the men positive for this have listed Irish, English, Dutch, Lebanese and Turkish (Armenian surname) ancestry. The number of STR marker values separating men in this group suggest G2a3b2 is a relatively old group despite the small number of men involved.

A clade of closely related Ashkenazi Jews represent virtually all G2b persons, with just three other G2b haplotypes having been reported so far: one Turk from Kars in northeast Turkey near Armenia, one Pashtun, and one Burusho in Pakistan. The extreme rarity of G2b in northern Pakistan could indicate that G2b in this area originates outside the region and was brought there in the historic period, perhaps from further west.

These two reported Pakistani G2b haplotypes are quite divergent from the Ashkenazi Jewish clade, and therefore do not at all indicate a recent common origin. The Turkish G2b is somewhat closer, but not identical. It remains to be seen if testing will reveal G2b haplotypes in other populations — this is some indication that G2b occurs at low levels in the Near East.

Knowing the distribution of haplogroup G in general is not as useful as that of the distribution of its subgroups. The subgroups likely spread to new areas of the world in different time periods and to different locations. All available G samples derive from studies or collections that do not meet criteria for random sampling, and conclusions based on them are only rough approximations of what is seen in populations.

In Europe west of the Black Sea Haplogroup G is found at about 5% of the population on average throughout most of the continent.

In Russia, the Ukraine and central Asia, the G percentage is around 1% or less. The northern slope of the Caucasus Mountains represents a major exception where concentrations in the Kabardinian and Ossetian populations are noted. In Digora, North Ossetia the highest known concentration of G in a single town in the world is reached where 74% of the tested men were G.

The Madjars of central Kazakhstan, a Kazakh sub-ethnic group, were found to be 87% G1. Other study on the Argyns found that 71% of them belong to G1. Haplogroup G is found as far east as northern China in small percentages where G can reach more substantial percentages in minority groups such as the Uyghurs.

Argyn tribe is one of the main constituents of the Kazakh people, of Turkic descent, and a main component in the Middle jüz sub-confederation in Kazakhstan, which historically consisted of three tribal conglomerations of Great jüz, Middle jüz, and Little jüz. It is found that 80 to 90% out of the 6 samples of Argyns belong to Haplogroup G1.

In Turkey, the southern Caucasus region and Iran, haplogroup G reaches the highest percentage of a regional population worldwide. Among Turkish males 11% of the population is G. In Iran, Haplogroup G reaches 13 to 15% of the population in various parts of the country. While it is found in percentages higher than 10% among the Bakhtiari, Gilaki and Mazandarani, it is closer to 5% among the Iranian Arabs and in some large cities.

Among the samples in the YHRD database from the southern Caucasus countries, 29% of the samples from Abazinia, 31% from Georgia, 18% from Azerbaijan and 11% from Armenia appear to be G samples.

In southern Asia, haplogroup G is found in concentrations of approximately 18% to 20% of Kalash, approximately 16% of Brahui, and approximately 11.5% of sampled Pashtun, but in only about 3% of the general Pakistani population. The many groups in India and Bangladesh have not been well studied. About 6% of the samples from Sri Lanka and Malaysia were reported as haplogroup G, but none were found in the other coastal lands of the Indian Ocean or Pacific Ocean in Asia.

In the Middle East, haplogroup G accounts for about 3% of the population in almost all areas. Among the Druze mostly residents of Israel 10% were found to be haplogroup G.

In Africa, haplogroup G is rarely found in sub-Saharan Africa or south of the horn of Africa among native populations. In Egypt, studies have provided information that pegs the G percentage there to be between 2% and 9%. 3% of North African Berbers were found to be haplogroup G. 2% of Arab Moroccans and 8% of Berber Moroccans were likewise found to be G.

In the Americas, the percentage of haplogroup G corresponds to the numbers of persons from Old World countries who emigrated. It is not found among Native Americans except where intermarriage with non-native persons has occurred. It has been found in Mexican mestizos.

Around 10% of Jewish males are Haplogroup G.

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