Haplogroup N1a (mtDNA)
Encyclopedia
In human mitochondrial genetics
Human mitochondrial genetics
Human mitochondrial genetics is the study of the genetics of the DNA contained in human mitochondria. Mitochondria are small structures in cells that generate energy for the cell to use, and are hence referred to as the "powerhouses" of the cell....

, Haplogroup N1a is a mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...

 (mtDNA) haplogroup
Haplogroup
In the study of molecular evolution, a haplogroup is a group of similar haplotypes that share a common ancestor having the same single nucleotide polymorphism mutation in both haplotypes. Because a haplogroup consists of similar haplotypes, this is what makes it possible to predict a haplogroup...

.

Origin

N1a originated in the Near East 12,000 to 32,000 years ago. Specifically, the Arabian Peninsula
Arabian Peninsula
The Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...

 is postulated as the geographic origin of N1a. This supposition is based on the relatively high frequency and genetic diversity of N1a in modern populations of the peninsula. Exact origins and migration patterns of this haplogroup are still subject of some debate.

Debate on Origin of Neolithic Europeans

Two competing scenarios exist for the spread of the Neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...

 from the Near East to Europe:
  1. Demic diffusion
    Demic diffusion
    Demic diffusion is a demographic term referring to a migratory model developed by Cavalli-Sforza, that consists of population diffusion into and across an area previously uninhabited by that group, possibly, but not necessarily, displacing, replacing, or intermixing with a pre-existing population...

     (in which farming is brought by farmers), for example Renfrew's Anatolian hypothesis
    Anatolian hypothesis
    The Anatolian hypothesis is also called Renfrew's Neolithic Discontinuity Theory ; it proposes that the dispersal of Proto-Indo-Europeans originated in Neolithic Anatolia...

  2. Cultural diffusion
    Cultural diffusion
    In cultural anthropology and cultural geography, cultural diffusion, as first conceptualized by Alfred L. Kroeber in his influential 1940 paper Stimulus Diffusion, or trans-cultural diffusion in later reformulations, is the spread of cultural items—such as ideas, styles, religions, technologies,...

     (in which farming is spread by the passage of ideas), which is the assumption in Alinei's Paleolithic Continuity Theory
    Paleolithic Continuity Theory
    The Paleolithic Continuity Theory , since 2010 relabelled as the Paleolithic Continuity Paradigm , is a hypothesis suggesting that the Proto-Indo-European language can be traced back to the Upper Paleolithic, several millennia earlier than the Chalcolithic or at the most Neolithic estimates in other...

    .


N1a became particularly prominent in this debate when a team led by Wolfgang Haak analyzed skeletons from Linear Pottery Culture
Linear Pottery culture
The Linear Pottery culture is a major archaeological horizon of the European Neolithic, flourishing ca. 5500–4500 BC.It is abbreviated as LBK , is also known as the Linear Band Ware, Linear Ware, Linear Ceramics or Incised Ware culture, and falls within the Danubian I culture of V...

 sites. The Linear Pottery Culture is credited with the first farming communities in Central Europe
Central Europe
Central Europe or alternatively Middle Europe is a region of the European continent lying between the variously defined areas of Eastern and Western Europe...

, marking the beginning of Neolithic Europe
Neolithic Europe
Neolithic Europe refers to a prehistoric period in which Neolithic technology was present in Europe. This corresponds roughly to a time between 7000 BC and c. 1700 BC...

 in the region some 7500 years ago. As of 2010, mitochondrial DNA analysis has been conducted on 42 specimens from five locations. Seven of the 42 specimens were found to be members of haplogroup N1a A separate study analyzed 22 skeletons from European hunter-gatherer sites dated 13400-2300 BC. Most of these remains were members of Haplogroup U, which was not found in any of the Linear Pottery Culture sites. Conversely, N1a was not identified in any of the hunter-gatherer fossils, indicating a genetic distinction between early European farmers and late European hunter-gatherers.

While no modern population is a close match to the LBK findings, the authors claim that the Linear Pottery population is most closely affiliated with modern Near East populations. Given this affiliation and the group's distinctiveness from hunter-gatherers, Haak's team concludes that "the transition to farming in central Europe was accompanied by a substantial influx of people from outside the region." However, they note that haplogroup frequencies in modern Europeans are substantially different from early farming and late hunter-gatherer populations. This indicates that "the diversity observed today cannot be explained by admixture between hunter-gatherers and early farmers alone" and that "major demographic events continued to take place in Europe after the early Neolithic."

Critics of these studies claim that the LBK N1a specimens could have derived from local communities established in Europe before the introduction of farming. Ammerman's team voiced concern due to some of the LBK specimens coming from communities several hundred years after farming was first established in the region; a rebuttal was given. In 2010, researchers led by Palanichamy conducted a genetic and phylogeographic analysis of N1a. Based on the results, they conclude that some of the LBK samples were indigenous to Europe while others may have resulted from 'leapfrog' colonization. Deguilloux's team agreed with Haak's conclusion on a genetic discontinuity between ancient and modern Europeans. However, they consider demic diffusion, cultural diffusion, and long-distance matrimonial exchanges all equally plausible explanations for the current genetic findings.

Historical Evidence

Seven of 42 skeletons from Linear Pottery Culture sites were found to be members of the N1a haplogroup (see Neolithic European section). N1a was also identified in remains from a 6200 year-old megalithic long mound near Prissé-la-Charrière
Prissé-la-Charrière
Prissé-la-Charrière is a commune in the Deux-Sèvres department in western France.Is located in Deux-Sèvres in the Poitou Charentes region of France. The closest airport to Prisse La Charriere is La Rochelle Airport slightly further afield are Angouleme Airport , Poitiers Airport , or Limoges...

, France. A 2500 year old fossil of a Scytho-Siberian in the Altai Republic
Altai Republic
Altai Republic is a federal subject of Russia . Its capital is the town of Gorno-Altaysk. The area of the republic is . Population: -Geography:...

, easternmost representative of the Scythians, was found to be a member of N1a1. A study of a 10th and 11th century Hungarians found that N1a1a1 was present in high-status individuals but absent from commoners. One of thirteen skeletons analyzed from a medieval cemetery dated 1250-1450 AD in Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

 was found to be a member of subclade N1a1a.

Distribution

Haplogroup N1a is widely distributed throughout Eurasia and Eastern Africa and is divided into the European/Central Asian and African/South Asian branches based on specific genetic markers.

Near East

Relatively high frequencies of N1a are found in the modern population of Saudi Arabia
Saudi Arabia
The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...

. Estimates range from 2.4% to 4%. Regional analysis revealed that the haplogroup was most common in the center of the country. Haplotype
Haplotype
A haplotype in genetics is a combination of alleles at adjacent locations on the chromosome that are transmitted together...

 diversity is noted for being higher here than elsewhere.

Frequencies of N1a in Yemen
Yemen
The Republic of Yemen , commonly known as Yemen , is a country located in the Middle East, occupying the southwestern to southern end of the Arabian Peninsula. It is bordered by Saudi Arabia to the north, the Red Sea to the west, and Oman to the east....

 are relatively high, with estimates varying by study: 3.6%, 5.2%, and 6.9%. Yemen is noted for high haplotype diversity within the population.

Elsewhere in the Near East, prevalence of N1a is lower. A 2008 article cited population frequencies of 1.1% in Qatar
Qatar
Qatar , also known as the State of Qatar or locally Dawlat Qaṭar, is a sovereign Arab state, located in the Middle East, occupying the small Qatar Peninsula on the northeasterly coast of the much larger Arabian Peninsula. Its sole land border is with Saudi Arabia to the south, with the rest of its...

, 0.3% in Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

, and 0.2% in Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

.

Europe

N1a is a rare haplogroup that currently appears in only 0.2% of European populations. Pockets of higher frequencies exist such as in Croatia
Croatia
Croatia , officially the Republic of Croatia , is a unitary democratic parliamentary republic in Europe at the crossroads of the Mitteleuropa, the Balkans, and the Mediterranean. Its capital and largest city is Zagreb. The country is divided into 20 counties and the city of Zagreb. Croatia covers ...

 where 0.7% of mainland Croatians, 9.24% of the population on the island of Cres
Cres
Cres is an Adriatic island in Croatia. It is one of the northern island in the Kvarner Gulf and can be reached via ferry from the island Krk or from the Istrian peninsula ....

, and 1.9% of the population on the island of Brač
Brac
Brač is an island in the Adriatic Sea within Croatia, with an area of 396 km², making it the largest island in Dalmatia, and the third largest in the Adriatic. Its tallest peak, Vidova Gora, or Mount St. Vid, stands at 778 m, making it the highest island point in the Adriatic...

 are members of N1a. In the Volga-Ural region of Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

, N1a is most prominent in the Komi-Permyaks (9.5%) followed by the Bashkirs
Bashkirs
The Bashkirs are a Turkic people indigenous to Bashkortostan extending on both parts of the Ural mountains, on the place where Europe meets Asia. Groups of Bashkirs also live in the republic of Tatarstan, Perm Krai, Chelyabinsk, Orenburg, Tyumen, Sverdlovsk, Kurgan, Samara and Saratov Oblasts of...

 (3.6%), Chuvash
Chuvash people
The Chuvash people are a Turkic ethnic group, native to an area stretching from the Volga Region to Siberia. Most of them live in Republic of Chuvashia and surrounding areas, although Chuvash communities may be found throughout all Russia.- Etymology :...

 (1.8%), and Tatars
Tatars
Tatars are a Turkic speaking ethnic group , numbering roughly 7 million.The majority of Tatars live in the Russian Federation, with a population of around 5.5 million, about 2 million of which in the republic of Tatarstan.Significant minority populations are found in Uzbekistan, Kazakhstan,...

 (0.4%). Russia as a whole has a frequency of 0.7%. A study of 542 individuals in Portugal
Portugal
Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

 found an N1a frequency of 0.37%. Only 0.11% of individuals analyzed in Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

 were members of the haplogroup.

Asia

Analysis of modern Siberian populations revealed a 1.2% prevalence in Altaians, 0.2% in the Buryats
Buryats
The Buryats or Buriyads , numbering approximately 436,000, are the largest ethnic minority group in Siberia and are mainly concentrated in their homeland, the Buryat Republic, a federal subject of Russia...

, and 0.9% in the Khanty people
Khanty people
Khanty / Hanti are an indigenous people calling themselves Khanti, Khande, Kantek , living in Khanty-Mansi Autonomous Okrug, a region historically known as "Yugra" in Russia, together with the Mansi. In the autonomous okrug, the Khanty and Mansi languages are given co-official status with Russian...

. In India, N1a was only identified in Indo-Aryan
Indo-Aryan languages
The Indo-Aryan languages constitutes a branch of the Indo-Iranian languages, itself a branch of the Indo-European language family...

 speakers at a frequency of 8.3%. All but one of the N1a individuals were members of the Havik
Havyaka Brahmin
Havyaka Brahmins are a Hindu Pancha Dravida Brahmin subsect primarily from the Indian state of Karnataka and Northern Kerala. Havyakas profess the Advaita philosophy propounded by Adi Shankaracharya.-Etymology:...

 group, a Brahmin
Brahmin
Brahmin Brahman, Brahma and Brahmin.Brahman, Brahmin and Brahma have different meanings. Brahman refers to the Supreme Self...

 upper caste.

Africa

Individuals with N1a have been identified in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...

, Ethiopia
Ethiopia
Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...

, Eritrea
Eritrea
Eritrea , officially the State of Eritrea, is a country in the Horn of Africa. Eritrea derives it's name from the Greek word Erethria, meaning 'red land'. The capital is Asmara. It is bordered by Sudan in the west, Ethiopia in the south, and Djibouti in the southeast...

, Somalia
Somalia
Somalia , officially the Somali Republic and formerly known as the Somali Democratic Republic under Socialist rule, is a country located in the Horn of Africa. Since the outbreak of the Somali Civil War in 1991 there has been no central government control over most of the country's territory...

, Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...

, and Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

. In Ethiopia, 2.2% of the population was found be members of N1a, but the haplogroup was only identified in Semitic
Semitic
In linguistics and ethnology, Semitic was first used to refer to a language family of largely Middle Eastern origin, now called the Semitic languages...

 speakers. In Egypt, 0.8% of the population were found to be members of N1a. A study of Kenyans found a prevalence of N1a to be around 10% in the Rendille population, and it was around 1% in the Maasai.

Tree

This phylogenetic tree of haplogroup N1a 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.
  • N
    • N1'5
      • N1
        • N1a'c'd'e'I
          • N1a'd'e'I
            • N1a'e'I
              • N1a
                • N1a1
                  • N1a1a
                    • N1a1a1
                      • N1a1a1a
                    • N1a1a2
                    • N1a1a3
                  • N1a1b


The tree of N1a has two distinct branches: Africa/South Asia and Europe with a Central Asian subcluster. However, the African branch has members in southern Europe, and the European branch has members in Egypt and the Near East. The Africa/South Asia branch is characterized by the 16147G mutation, whereas the European branch is characterized by 16147A, 3336, and 16320. The Central Asian subcluster is an offshoot of the European branch that is characterized by marker 16189.

Subclade N1a1 is associated with mutation 16147A. Palanichamy calculates N1a1 to have emerged between 8900 to 22400 YBP. Subclade N1a1a is denoted by marker 16320, and is therefore associated with the "European" N1a branch. Petraglia estimates that N1a1a arose between 11000 to 25000 YBP.

See also

  • Genealogical DNA test
    Genealogical DNA test
    A genealogical DNA test examines the nucleotides at specific locations on a person's DNA for genetic genealogy purposes. The test results are not meant to have any informative medical value and do not determine specific genetic diseases or disorders ; they are intended only to give genealogical...

  • Genetic Genealogy
    Genetic genealogy
    Genetic genealogy is the application of genetics to traditional genealogy. Genetic genealogy involves the use of genealogical DNA testing to determine the level of genetic relationship between individuals.-History:...

  • Human mitochondrial genetics
    Human mitochondrial genetics
    Human mitochondrial genetics is the study of the genetics of the DNA contained in human mitochondria. Mitochondria are small structures in cells that generate energy for the cell to use, and are hence referred to as the "powerhouses" of the cell....

  • Population Genetics
    Population genetics
    Population genetics is the study of allele frequency distribution and change under the influence of the four main evolutionary processes: natural selection, genetic drift, mutation and gene flow. It also takes into account the factors of recombination, population subdivision and population...

  • Human mitochondrial DNA haplogroups
    Human mitochondrial DNA haplogroups
    In human genetics, a human mitochondrial DNA haplogroup is a haplogroup defined by differences in human mitochondrial DNA. Haplogroups are used to represent the major branch points on the mitochondrial phylogenetic tree...


External links

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