Haplogroup U descends from a woman in the Haplogroup R (mtDNA) branch of the phylogenetic tree, who lived around 55,000 years ago.
Haplogroup U is found in 15% of Indian caste and 8% of Indian tribal populations. U is found in approximately 11% of native Europeans and is held as the oldest maternal haplogroup found in that region. Haplogroup U is subdivided into Haplogroups U1-U9. Haplogroup K is a subclade of U8. The old age has led to a wide distribution of the descendant subgroups across Western Eurasia, North Africa, and South Asia. Some subclades of U have a more specific geographic range.
Haplogroup U1 seems to appear mostly in the Middle East; however low frequency results appear scattered throughout Europe particularly in the Mediterranean. U1 is found in Svanetia (Georgia, Caucasus) at 4.2%. U1a in particular is found from India to Europe, but is extremely rare among the northern and Atlantic fringes of Europe including the British Isles and Scandinavia. Several examples in Tuscany have been noted. In India U1a has been found in the Kerala region. U1b has a similar spread but is rarer than U1a. Some examples of U1b have been found among Jewish diaspora. U1a and U1b appear in equal frequency in eastern Europe.
Haplogroup U2 is most common in South Asia but also found in low frequency in Central and West Asia, as well as in Europe as U2e. The overall frequency of U2 in South Asia is largely accounted for by the group U2i, whereas haplogroup U2e, common in Europe, is entirely absent; given that these lineages diverged approximately 50kya, these data have been interpreted as indicating very low maternal-line gene-flow between South Asia and Europe throughout this period.
This haplogroup has been found in the remains of a 30,000-year-old hunter-gatherer in South European Russia (Kostenki).
Haplogroup U3 is defined by the HVR1transition A16343G. It is found at low levels throughout Europe (about 1% of the population), the Near East (about 2.5% of the population), and Central Asia (1%). U3 is present at higher levels among populations in the Caucasus (about 6%) in Svan population from Svaneti region(Georgia, Caucasus) 4,2% and among Lithuanian Romani, Polish Romani, and Spanish Romani populations (36-56%).
Haplogroup U4 has its origin in the Upper Palaeolithic, dating to approximately 25,000 years ago. It is widely distributed in Europe, and has been implicated in the expansion of modern humans into Europe occurring before the Last Glacial Maximum. Found in Svan population from Svaneti region (Georgia, Caucasus) 8,3%
Haplogroup U4 (Ulrike) is a small Indo-European haplogroup that is particularly prevalent in Finland and Russia. It is found at low frequencies throughout Europe, North America and Asia. We have project members living in the following countries: Australia, Austria, Bahamas, Belgium, Brazil, Canada, Czech Republic, Denmark, England, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Lithuania, Macedonia, The Netherlands, New Zealand, Norway, Poland, Romania, Russia, Scotland, South Africa, Spain, Sweden, Switzerland, Turkey, Virgin Islands, West Indies, USA. 
The clan of Ulrike (German for Mistress of All) is not among the original "Seven Daughters of Eve" clans, but with just under 2% of Europeans among its members, it has a claim to being included among the numerically important clans. Ulrike lived about 18,000 years ago in the cold refuges of the Ukraine at the northern limits of human habitation. Though Ulrike's descendants are nowhere common, the clan is found today mainly in the east and north of Europe with particularly high concentrations in Scandinavia and the Baltic states. 
The age of U5 is estimated at 30-50,000 years. Approximately 11% of total Europeans and 10% of European-Americans are in haplogroup U5.
U5 has been found in human remains dating from the Mesolithic in England, Germany, Lithuania, Poland, Portugal, Russia, Sweden, France  and Spain.  Haplogroup U5 and its subclades U5a and U5b form the highest population concentrations in the far north, in Sami, Finns, and Estonians, but it is spread widely at lower levels throughout Europe. This distribution, and the age of the haplogroup, indicate individuals from this haplogroup were part of the initial expansion tracking the retreat of ice sheets from Europe around 10.000 years ago.
Haplogroup U5 is found also in small frequencies and at much lower diversity in the Near East and parts of northern Africa (areas with sizable U6 concentrations), suggesting back-migration of people from Europe to the south.
Mitochondrial haplogroup U5a has also been associated with HIV infected individuals displaying accelerated progression to AIDS and death.
U5 has polymorphisms in the locations of 3197 9477 13617 16192 16270
U5a arose around 20000 years ago and has polymorphisms in 14793 16256 ( + U5 polymorphisms).
U5a1 arose around 16000 years ago and has polymorphisms in 15218 16399( + U5a polymorphisms).
U5a1a arose around 15000 years ago and has polymorphisms in 1700 16192( + U5a1 polymorphisms).
U5a1a1 arose around 12000 years ago and has polymorphisms in 5495 15924( + U5a1a polymorphisms).
U5a1a1a arose around 600 AC  and has polymorphisms in 3816 (A3816G)(and has lost its polymorphism in 152 (backmutation) + U5a1a1 polymorphisms).
U5a1a1b arose around 3300 years ago  and has polymorphisms in 15110 (G15110A) (and has lost its polymorphism in 152 (backmutation) + U5a1a1 polymorphisms).
U5a1a1c has polymorphisms in 6905 (A6905G) 13015 (T13015C)+ U5a1a1 polymorphisms).
U5a1a1d arose around 0 AC  and has polymorphisms: G185A T204C T16362C (and has lost its polymorphism in 152 (backmutation) + U5a1a1 polymorphisms).
U5a1a2 arose around 10000 years ago  and has polymorphisms in 573.1C (deletion) 12346( + U5a1a polymorphisms).
U5a1a2a arose around 800 BC  and has polymorphisms in 5319 6629 6719( + U5a1a2 polymorphisms).
U5a1a2a1 arose around 400 AC  and has polymorphisms T6293C ( + U5a1a2a polymorphisms).
U5a1b arose around 8500 years ago and has polymorphisms in 9667 (A9667G) ( + U5a1 polymorphisms).
U5a1b1 arose around 7000 years ago and has polymorphisms in 16291 (C16291T) ( + U5a1b polymorphisms).
U5a1b1a arose around 5000 years ago  and has polymorphisms T4553C + U5a1b1 polymorphisms).
U5a1b1a1 arose around 500 AC and has polymorphisms C14574T + U5a1b1a polymorphisms).
U5a1b1b arose around 3000 years ago  and has polymorphisms in 8119 (T8119C)( + U5a1b1 polymorphisms).
U5a1b1c arose around 5000 years ago  and has polymorphisms in 9055 (G9055A)( + U5a1b1 polymorphisms).
U5a1b1c1 arose around 500 BC  and has polymorphisms in 1187 (T1187C)( + U5a1b1c polymorphisms).
U5a1b1c2 arose around 500 BC  and has polymorphisms in 3705 (G3705A)( + U5a1b1c polymorphisms).
U5a1b1d has polymorphisms in 12358 16093 ( + U5a1b1 polymorphisms).
U5a1b1e has polymorphisms in 12582 16192 16294 ( + U5a1b1 polymorphisms).
U5a1b2 has polymorphisms in 9632 ( + U5a1b polymorphisms).
U5a1b3 has polymorphisms in 16362 16428 ( + U5a1b polymorphisms).
U5a1c arose around 13000 years ago and has polymorphisms in 16320 ( + U5a1 polymorphisms).
U5a1c1 has polymorphisms in 195 13802 ( + U5a1c polymorphisms).
U5a1c2 has polymorphisms in 961 965.1C (deletion)( + U5a1c polymorphisms).
U5a1d arose around 19000 years ago and has polymorphisms in 3027 ( + U5a1 polymorphisms).
U5a1d1 has polymorphisms in 5263 13002 (to adenosine)( + U5a1d polymorphisms).
U5a1d2 has polymorphisms in 573.1C (deletion) 3552 (+ U5a1d polymorphisms).
U5a1d2a has polymorphisms in 195 4823 5583 16145 16189 (+ U5a1d2 polymorphisms).
U5a1e has polymorphisms in 3564 8610 ( + U5a1 polymorphisms).
U5a1f has polymorphisms in 6023 ( + U5a1 polymorphisms).
U5a2 arose around 14000 years ago and has polymorphisms in 16526( + U5a polymorphisms).
U5a2a arose around 6000 years ago and has polymorphisms in 13827 13928C 16114 16294 ( + U5a2 polymorphisms).
U5a2b arose around 8000 years ago and has polymorphisms in 9548 ( + U5a2 polymorphisms).
U5a2c arose around 13000 years ago and has polymorphisms in 10619( + U5a2 polymorphisms).
U5a2d and has polymorphisms in 7843 7978 8104 11107 16192! (backmutated in 16192 to the original Cambridge sequence) ( + U5a2 polymorphisms).
U5a2e and has polymorphisms in 151 152 3768 15289 16189 16311 16362 ( + U5a2 polymorphisms).
U5b arose around 24000 years ago and has polymorphisms in 150 7768 14182( + U5 polymorphisms).
U5b1 arose around 18000 years ago and has polymorphisms in 5656( + U5b polymorphisms).
U5b1a has polymorphisms in 5656 15097, 16189 and has lost its polymorphism in 7028 (backmutation)( + U5b1 polymorphisms).
U5b1b: has been found in Fulbe and Papel people in Guinea-Bissau and Yakuts people of northeastern Siberia. It arose around 11000 years ago and has polymorphisms in 12618 16189 ( + U5b1 polymorphisms).
U5b1c has polymorphisms in 5656 15191, 16189, 16311 + U5b1 polymorphisms) and arose about 13000 years ago.
U5b1d has polymorphisms in 5437 5656 and has lost its polymorphism in 16192 (backmutation)( + U5b1 polymorphisms).
U5b1e has polymorphisms in 152 2757 10283 12616 16189 and has lost its polymorphism in 16192 (backmutation)( + U5b1 polymorphisms) and arose about 6600 years ago. U5b1e is mainly seen in central Europe among Czechs, Slovaks, Hungarians and southern Russians.
U5b1g has polymorphisms in 151 228 573.1C 5656 10654 13759 14577 ( + U5b1 polymorphisms).
U5b2 arose around 24000 years ago and has polymorphisms in 1721 13637( + U5b polymorphisms).
U5b3: The subclade is found primary on the island of Sardinia.
Haplogroup U6 was named 'Ulla' by Bryan Sykes. It is common (around 10% of the people)  in North Africa (with a maximum of 29% in an Algerian Mozabites) and the Canary Islands (18% on average with a peak frequency of 50.1% in La Gomera). It is also found in the Iberian peninsula, where it has the highest diversity (10 out of 19 sublineages are only found in this region and not in Africa), Eastern Africa and occasionally in other locations.
U6 is thought to have entered North Africa around 30,000 years ago from the Near-East. In spite of the highest diversity of Iberian U6, Maca-Meyer argues for an Near East origin of this clade based on the highest diversity of subclade U6a in that region, where it would have arrived from West Asia. She estimates the age of U6 between 25,000 and 66,000 years BP. However U6 has its highest frequencies in North Africa and seems to be a specific haplogroup of that region.
Subgroup U6a reflects the first African expansion from the Maghrib returning to the east. Derivative clade U6a1 signals a posterior movement from East Africa back to the Maghrib and the Near East. This migration coincides with the probable Afroasiatic linguistic expansion. U6b and U6c clades, restricted to West Africa, had more localized expansions. U6b probably reached the Iberian Peninsula during the Capsian diffusion in North Africa. Two autochthonous derivatives of these clades (U6b1 and U6c1) indicate the arrival of North African settlers to the Canarian Archipelago in prehistoric times, most probably due to the Saharan desiccation. The absence of these Canarian lineages nowadays in Africa suggests important demographic movements in the western area of this Continent.
U6a: it is the most widespread (from Canary Islands and Iberian Peninsula to Syria, Ethiopia and Kenya) and has highest diversity in Eastern Africa. Estimated age: 24-27,500 BP. It has one major subclade:
U6a1: with similar distribution to U6a. Estimated age: 15-20,000 BP. Found in Brittany (France) at 4.5% frequency.
U6b: shows a more patched and western distribution. In the Iberian peninsula U6b is more frequent in the North (while U6a is in the South). It has also been found in low amounts in Morocco, Algeria, Senegal and Nigeria. Estimated age: 8,500-24,500 BP. It has one subclade:
U6b1: found only in the Canary Islands and in the Iberian peninsula. Estimated age: c. 6000 BP.
U6c: only found in Morocco and Canary Islands. Estimated age: 6,000-17,500 BP.
U6a and U6b share a common basal mutation (16219) that is not present in U6c.
Many European populations lack Haplogroup U7, but its frequency climbs over 4% in the Near East and up to 5% in Pakistan, reaching nearly 10% level in Iranians. However, it was present in Northern Europe before the Middle Ages, and it was carried by a wealthy woman, perhaps of their Royal Clan, buried in the Viking Oseberg ship in Norway. In India, haplogroup U7 frequency peaks at over 12% in Gujarat, the westernmost state of India, while for the whole of India its frequency stays around 2%. Expansion times and haplotype diversities for the Indian and Near and Middle Eastern U7 mtDNAs are strikingly similar. The possible homeland of this haplogroup spans Indian Gujarat and Iran because from there its frequency declines steeply both to the east and to the west. If the origin were in Iran rather than in India, then its equally high frequency as well as diversity in Gujarat favors a scenario whereby U7 has been introduced to the coastal western India either very early, or by multiple founders.
U8a: The Basques have the most ancestral phylogeny in Europe for the mitochondrial haplogroup U8a, a rare subgroup of U8, placing the Basque origin of this lineage in the Upper Palaeolithic. The lack of U8a lineages in Africa suggests that their ancestors may have originated from West Asia.
U8b: This clade has been found in Italy and Jordan.
Haplogroup K makes up a sizeable fraction of European and West Asian mtDNA lineages. It is now known it is actually a subclade of haplogroup U8b'K, and is believed to have first arisen in northeastern Italy. Haplogroup UK shows some evidence of being highly protective against AIDS progression.
Haplogroup U9 is a rare clade in mtDNA phylogeny, characterized only recently in a few populations of Pakistan (Quintana-Murci et al. 2004). Its presence in Ethiopia and Yemen, together with some Indian-specific M lineages in the Yemeni sample, points to gene flow along the coast of the Arabian Sea. Haplogroups U9 and U4 share two common mutations at the root of their phylogeny. It is interesting that, in Pakistan, U9 occurs frequently only among the so-called “negroid Makrani” population. In this particular population, lineages specific to sub-Saharan Africans occur as frequently as 39%, which suggests that U9 lineages in Pakistan may have an African origin (Quintana-Murci et al. 2004). Regardless of which coast of the Arabian Sea may have been the origin of U9, its Ethiopian–southern Arabian–Indus Basin distribution hints that its diversification from U4 may have occurred in regions far away from the current area of the highest diversity and frequency of haplogroup U4—East Europe and western Siberia.
This phylogenetic tree of haplogroup U subclades is based on the paper by Mannis van Oven and Manfred Kayser Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation and subsequent published research.
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