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|artikkeliteksti=<P align="justify"> In Europe, molecular anthropology is generally used to refer to a new departure in genetic research which has come to be employed alongside archaeology and historical linguistics in investigating the origins of peoples. European molecular anthropologists typically come from evolutionary biology and medicine. In the United States, molecular anthropology has been used since the 1960s to refer to a special branch of physical (biological) anthropology in which population genetics is applied to investigating the molecular evolution and genetic variation of the human race. American molecular anthropologists are thus typically physical anthropologists who have trained in schools of anthropology and who in addition have a competence in cultural anthropology, archaeology and linguistics.</P>  
 
|artikkeliteksti=<P align="justify"> In Europe, molecular anthropology is generally used to refer to a new departure in genetic research which has come to be employed alongside archaeology and historical linguistics in investigating the origins of peoples. European molecular anthropologists typically come from evolutionary biology and medicine. In the United States, molecular anthropology has been used since the 1960s to refer to a special branch of physical (biological) anthropology in which population genetics is applied to investigating the molecular evolution and genetic variation of the human race. American molecular anthropologists are thus typically physical anthropologists who have trained in schools of anthropology and who in addition have a competence in cultural anthropology, archaeology and linguistics.</P>  
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<P align="justify"> Molecular anthropological research can be claimed to have started when scientists began to compare the frequencies of ABO blood groups (A, B, AB and O) in different human populations soon after the First World War. The discovery of the structure of the DNA molecule in the 1950s led to an increase in the interest of physical anthropologists in research at the molecular level. In the 1960s, serological research displaced phenotypical investigations in explicating the genetic relations between different human populations. In the same decade, comparisons began between humans and other primates with respect to the amino acid sequences of haemoglobin, and molecular research into human evolution and variation began to be called molecular anthropology.</P>  
 
<P align="justify"> Molecular anthropological research can be claimed to have started when scientists began to compare the frequencies of ABO blood groups (A, B, AB and O) in different human populations soon after the First World War. The discovery of the structure of the DNA molecule in the 1950s led to an increase in the interest of physical anthropologists in research at the molecular level. In the 1960s, serological research displaced phenotypical investigations in explicating the genetic relations between different human populations. In the same decade, comparisons began between humans and other primates with respect to the amino acid sequences of haemoglobin, and molecular research into human evolution and variation began to be called molecular anthropology.</P>  
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<P align="justify"> Molecular anthropology has benefited greatly from the breakthrough in genetic engineering that began in the 1980s, and which since the late 1990s has permitted a direct genetic comparison between present-day humans and fossilized remains, such as those of Neanderthal humans, which are tens of thousands of years old. At the moment, the major problem for molecular anthropological and other genetic research is the fact that genetic engineering has developed faster than theory. This could easily lead to misinterpretation of the results that are obtained from it.</P>  
 
<P align="justify"> Molecular anthropology has benefited greatly from the breakthrough in genetic engineering that began in the 1980s, and which since the late 1990s has permitted a direct genetic comparison between present-day humans and fossilized remains, such as those of Neanderthal humans, which are tens of thousands of years old. At the moment, the major problem for molecular anthropological and other genetic research is the fact that genetic engineering has developed faster than theory. This could easily lead to misinterpretation of the results that are obtained from it.</P>  
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<P align="justify"> The scope of molecular anthropological research today is very broad. Some molecular anthropologists study the genetic relations between man and other primates (anthropoids, apes and lemuroids), the genetic structures of human and other primate populations, the microevolution of the human race (changes in the genetic structure of a population from one generation to the next), the genetic relations between peoples, or the origins of peoples and the DNA of archaeological finds of individuals. Others may for example use genetic paternity tests to ascertain which of the males in a group of chimpanzees is the father of which children, or they may carry out forensic anthropological work by examining the DNA isolated from the bones of the skeleton of an unknown corpse in order to ascertain its identity. Molecular anthropologists investigate the origins and the relationships between populations through a study of DNA. The differences in DNA sequences between populations in those parts of the DNA that do not carry genetic coding are more reliable indicators of genetic relationships between populations than selective phenotypical features and the genes that affect them. Therefore, molecular anthropological research is moving away from the so-called classical indicators of cellular DNA (e.g. the comparison of blood groups) to the study of microsatellites (DNA). These so-called tandem copies comprise the majority of DNA, they are neutral with respect to selection, and they have a relatively high incidence of mutation. The DNA of the cell nucleus is used mainly in estimating the genetic distances between different populations. </P>  
 
<P align="justify"> The scope of molecular anthropological research today is very broad. Some molecular anthropologists study the genetic relations between man and other primates (anthropoids, apes and lemuroids), the genetic structures of human and other primate populations, the microevolution of the human race (changes in the genetic structure of a population from one generation to the next), the genetic relations between peoples, or the origins of peoples and the DNA of archaeological finds of individuals. Others may for example use genetic paternity tests to ascertain which of the males in a group of chimpanzees is the father of which children, or they may carry out forensic anthropological work by examining the DNA isolated from the bones of the skeleton of an unknown corpse in order to ascertain its identity. Molecular anthropologists investigate the origins and the relationships between populations through a study of DNA. The differences in DNA sequences between populations in those parts of the DNA that do not carry genetic coding are more reliable indicators of genetic relationships between populations than selective phenotypical features and the genes that affect them. Therefore, molecular anthropological research is moving away from the so-called classical indicators of cellular DNA (e.g. the comparison of blood groups) to the study of microsatellites (DNA). These so-called tandem copies comprise the majority of DNA, they are neutral with respect to selection, and they have a relatively high incidence of mutation. The DNA of the cell nucleus is used mainly in estimating the genetic distances between different populations. </P>  
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<P align="justify"> Molecular anthropologists are particularly interested in mtDNA and Y-DNA because the former permits the elucidation of the origins of female ancestors and the latter of male ancestors, and consequentlyit is possible toreconstruct ancient migrations. The family tree of maternal lines has been reconstructed to a common original form (a mitochondrial eEve f), and that of paternal lines to their common original form (an eAdam f). Contrary to common belief, these original forms did not necessarily belong to the last common original mother and father of all human beings because mtDNA and Y-DNA are particularly susceptible to genetic drift (chance). The maternal line vanishes if the woman does not have any daughters, and the paternal line if the man has no sons.</P> <P align="justify"> Genetic drift is most likely to take place when a population goes through a so-called genetic bottleneck. This happens, for example, when a group becomes detached from the main population and migrates elsewhere. The descendents of these so-called efounders f have a random collection of the paternal and maternal lines in the original population. A population also passes through a genetic bottleneck when it rapidly decreases in size. In such a situation, rare maternal and paternal lines (and their nuclear DNA indicators) can easily disappear.</P>  
 
<P align="justify"> Molecular anthropologists are particularly interested in mtDNA and Y-DNA because the former permits the elucidation of the origins of female ancestors and the latter of male ancestors, and consequentlyit is possible toreconstruct ancient migrations. The family tree of maternal lines has been reconstructed to a common original form (a mitochondrial eEve f), and that of paternal lines to their common original form (an eAdam f). Contrary to common belief, these original forms did not necessarily belong to the last common original mother and father of all human beings because mtDNA and Y-DNA are particularly susceptible to genetic drift (chance). The maternal line vanishes if the woman does not have any daughters, and the paternal line if the man has no sons.</P> <P align="justify"> Genetic drift is most likely to take place when a population goes through a so-called genetic bottleneck. This happens, for example, when a group becomes detached from the main population and migrates elsewhere. The descendents of these so-called efounders f have a random collection of the paternal and maternal lines in the original population. A population also passes through a genetic bottleneck when it rapidly decreases in size. In such a situation, rare maternal and paternal lines (and their nuclear DNA indicators) can easily disappear.</P>  
<P align="justify"> Although mtDNA and Y-DNA provide more information about ancient migrations because of the founder effect, nuclear DNA is a more reliable indicator of genetic relationships between peoples. This is because of the greater vulnerability of mtDNA and Y-Dna to genetic drift and also because in most communities a woman moves into the home of her husband when she marries. Neighbouring populations which have exchanged genes over many generations, but which have separate origins, typically have many of the same maternal lines and few of the same paternal lines, and the genetic distances calculated on the basis of nuclear DNA indicators show that they are genetically close to each other. Therefore the origins of peoples and the relationships between them should not be reconstructed on the basis of mtDNA alone. Molecular anthropological research will in the coming years provide more exact information about the molecular evolution of the human race and about the origins of peoples and the relationships between them. Our knowledge about Y-DNA variation in particular will increase. </P><BR><BR> {{Artikkelilinkki|0601|DNA}} <BR> {{Artikkelilinkki|0637|Population genetics}}
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<P align="justify"> Although mtDNA and Y-DNA provide more information about ancient migrations because of the founder effect, nuclear DNA is a more reliable indicator of genetic relationships between peoples. This is because of the greater vulnerability of mtDNA and Y-Dna to genetic drift and also because in most communities a woman moves into the home of her husband when she marries. Neighbouring populations which have exchanged genes over many generations, but which have separate origins, typically have many of the same maternal lines and few of the same paternal lines, and the genetic distances calculated on the basis of nuclear DNA indicators show that they are genetically close to each other. Therefore the origins of peoples and the relationships between them should not be reconstructed on the basis of mtDNA alone. Molecular anthropological research will in the coming years provide more exact information about the molecular evolution of the human race and about the origins of peoples and the relationships between them. Our knowledge about Y-DNA variation in particular will increase. </P>  
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{{Artikkelilinkki|20140806094235| Table of contents: Demography, ethnicity and physical anthropology}}<BR><BR>
 
|kirjoittaja=Markku Niskanen
 
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Versio 30. joulukuuta 2014 kello 15.14

Molekyyliantropologia

Euroopassa molekyyliantropologialla tarkoitetaan yleensä geenitutkimuksen uutta tutkimussuuntausta, joka on tullut arkeologian ja kielentutkimuksen rinnalle kansojen alkuperien selvittelyssä. Eurooppalaiset molekyyliantropologista tutkimusta tekevät tutkijat ovat tyypillisesti evoluutiobiologeja tai lääketieteen edustajia. Yhdysvalloissa molekyyliantropologia on 1960-luvulta lähtien tarkoittanut fyysisen (eli biologisen) antropologian erikoistumisalaa, jossa populaatiogenetiikkaa sovelletaan ihmislajin molekyylievoluution ja geneettisen variaation tutkimisessa. Amerikkalaiset molekyyliantropologit ovat tyypillisesti antropologian laitosten kouluttamia fyysisiä antropologeja, joilla on fyysisen antropologian koulutuksen lisäksi kulttuuriantropologian, arkeologian ja kielentutkimuksen koulutusta.

Molekyyliantropologisen tutkimuksen voidaan sanoa alkaneen, kun tutkijat alkoivat verrata eri ihmispopulaatioiden ABO-veriryhmien (A, B, AB ja O) esiintymistiheyksiä pian ensimmäisen maailmansodan jälkeen. 1950-luvulla tapahtunut DNA-molekyylirakenteen selvittely johti fyysisten antropologien kasvavaan kiinnostukseen molekyylitason tutkimusta kohtaan. 1960-luvulla serologiset tutkimukset syrjäyttivät fenotyyppiset tutkimukset ihmispopulaatioiden geneettisten sukulaissuhteiden selvittelyssä. Saman vuosikymmenen aikana alkoivat ihmisten ja muiden kädellisten geneettiset vertailut hemoglobiinin aminohapposekvenssien valossa ja ihmisen evoluution ja variaation tutkimusta molekyylitasolla alettiin kutsua molekyyliantropologiaksi.

Molekyyliantropologia on hyötynyt erittäin paljon 1980-luvulla alkaneesta geeniteknologian läpimurrosta, mikä on 1990-luvun lopulta lähtien sallinut joidenkin jopa kymmeniä tuhansia vuosia vanhojen fossiiliyksilöiden (esim. neandertalinihmisten) suoran geneettisen vertailun nykyisten ihmisten kanssa. Tällä hetkellä molekyyliantropologisen ja muun geneettisen tutkimuksen suuri ongelma on se, että geeniteknologia on kehittynyt teoriaa nopeammin. Tämä voi johtaa tulosten virheellisiin tulkintoihin.

Molekyyliantropologien tutkimusalue on nykyisin varsin laaja. He tutkivat ihmisten ja muiden kädellisten (ihmisapinoiden, apinoiden ja puoliapinoiden) geneettisiä sukulaissuhteita, ihmis- ja muiden kädellispopulaatioiden geneettistä rakennetta, ihmislajin mikroevoluutiota (eli sukupolvien kuluessa tapahtuvia muutoksia populaation geneettisessä rakenteessa), kansojen geneettisiä sukulaissuhteita ja alkuperiä sekä arkeologisten yksilöiden DNA:ta. He voivat myöskin selvitellä geneettisten vanhemmuustestien avulla esimerkiksi mikä simpanssiryhmän uroksista on kunkin poikasen isä. He tekevät myöskin ns. oikeusantropologista työtä tutkimalla tunnistamattoman luurangoksi maatuneen henkilön luista eristettyä DNA:ta henkilöllisyyden selvittelemiseksi.

Molekyyliantropologit selvittelevät populaatioiden alkuperiä ja sukulaissuhteista tutkimalla DNA:ta. Populaatioiden väliset DNA-sekvenssi erot niissä osissa DNA:ta, jotka eivät kanna geneettistä koodia, ovat luotettavampia indikaattoreita populaatioiden välisistä geneettisistä sukulaissuhteista kuin valinnan alaiset fenotyyppiset piirteet ja niihin vaikuttavat geenit. Tämän vuoksi molekyyliantropologinen tutkimus on siirtymässä tuman DNA:n ns. klassisista merkkitekijöistä (esim. veriryhmien vertailusta) mikrosatelliittien (ks. DNA) tutkimukseen. Nämä ns. tandem-toistot kattavat hyvin suuren osan DNA:ta, ne ovat valinnan suhteen neutraaleja ja niillä on suhteellisen suuri mutaatiotiheys. Tuman DNA:ta käytetään erityisesti eri populaatioiden välisten geneettisten etäisyyksien arvioimisiin.

Molekyyliantropologit ovat erityisen kiinnostuneita mtDNA:sta ja Y-DNA:sta, koska mtDNA sallii esiäitien ja Y-DNA esi-isien alkuperien, ja siten muinaisten migraatioiden rekonstruktion. Äitilinjojen sukupuu on rekonstruoitu niiden yhteiseen kantamuotoon (ns. mitokondriaaliseen "Eevaan") ja isälinjojen sukupuu niiden yhteiseen kantamuotoon ("Aatamiin"). Vastoin yleistä oletusta, nämä kantamuodot eivät välttämättä kuuluneet kaikkien nykyisten ihmisten viimeiselle yhteiselle kantaäidille ja kantaisälle, koska mtDNA ja Y-DNA ovat erityisen alttiita geneettiselle ajautumiselle (sattumalle). Äitilinja katoaa, jos nainen ei saa tyttäriä, ja isälinja katoaa, jos mies ei saa poikia.

Geneettistä ajautumista tapahtuu etenkin, jos populaatio menee geneettisen pullonkaulan läpi. Tämä tapahtuu esimerkiksi niin, että ryhmä yksilöitä erkaantuu kantapopulaatioistaan ja siirtyy uudelle alueelle. Näiden ns. perustajajäsenten jälkeläisillä on sattumanvarainen kokoelma kantapopulaatiossa esiintyvistä äiti- ja isälinjoista. Populaatio menee geneettisen pullonkaulan läpi myös, kun sitä kohtaa väestökato. Tällöin harvinaiset äiti- ja isälinjat (sekä tuman DNA:n merkkitekijät) ovat suuressa vaarassa kadota.

Vaikka mtDNA ja Y-DNA antavat perustajavaikutuksen ansiosta enemmän tietoa muinaisista migraatioista, tuman DNA on luotettavampi indikaattori populaatioiden geneettisistä sukulaissuhteista. Tämä johtuu mtDNA:n ja Y-DNA:n suuremmasta alttiudesta geneettiselle ajautumiselle sekä siitä, että useimmissa yhteisöissä nainen muuttaa avioiduttuaan miehensä luo. Monen sukupolven ajan geenejä vaihtavilla, mutta alun perin eri suunnilta tulleilla naapuripopulaatioilla onkin tyypillisesti paljon samoja äitilinjoja, vähän samoja isälinjoja ja tuman DNA:n merkkitekijöistä lasketut geneettiset etäisyydet osoittavat niiden olevan geneettisesti lähellä toisiaan. Tämän vuoksi kansojen alkuperien ja sukulaissuhteinen rekonstruktiota ei pidä tehdä esimerkiksi yksinomaan mtDNA:n valossa.

Molekyyliantropologiset tutkimukset tulevat lähi vuosina antamaan nykyistä tarkempaa tietoa ihmislajin molekyylievoluutiosta sekä kansojen alkuperistä ja sukulaissuhteista. Etenkin tietämys Y-DNA:n variaatiosta tulee lisääntymään.

DNA-tutkimus
väestögenetiikka / populaatiogenetiikka

Sisällysluettelo: Demografia, etnisiteetti ja fyysinen antropologia

Markku Niskanen



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Molecular anthropology

In Europe, molecular anthropology is generally used to refer to a new departure in genetic research which has come to be employed alongside archaeology and historical linguistics in investigating the origins of peoples. European molecular anthropologists typically come from evolutionary biology and medicine. In the United States, molecular anthropology has been used since the 1960s to refer to a special branch of physical (biological) anthropology in which population genetics is applied to investigating the molecular evolution and genetic variation of the human race. American molecular anthropologists are thus typically physical anthropologists who have trained in schools of anthropology and who in addition have a competence in cultural anthropology, archaeology and linguistics.

Molecular anthropological research can be claimed to have started when scientists began to compare the frequencies of ABO blood groups (A, B, AB and O) in different human populations soon after the First World War. The discovery of the structure of the DNA molecule in the 1950s led to an increase in the interest of physical anthropologists in research at the molecular level. In the 1960s, serological research displaced phenotypical investigations in explicating the genetic relations between different human populations. In the same decade, comparisons began between humans and other primates with respect to the amino acid sequences of haemoglobin, and molecular research into human evolution and variation began to be called molecular anthropology.

Molecular anthropology has benefited greatly from the breakthrough in genetic engineering that began in the 1980s, and which since the late 1990s has permitted a direct genetic comparison between present-day humans and fossilized remains, such as those of Neanderthal humans, which are tens of thousands of years old. At the moment, the major problem for molecular anthropological and other genetic research is the fact that genetic engineering has developed faster than theory. This could easily lead to misinterpretation of the results that are obtained from it.

The scope of molecular anthropological research today is very broad. Some molecular anthropologists study the genetic relations between man and other primates (anthropoids, apes and lemuroids), the genetic structures of human and other primate populations, the microevolution of the human race (changes in the genetic structure of a population from one generation to the next), the genetic relations between peoples, or the origins of peoples and the DNA of archaeological finds of individuals. Others may for example use genetic paternity tests to ascertain which of the males in a group of chimpanzees is the father of which children, or they may carry out forensic anthropological work by examining the DNA isolated from the bones of the skeleton of an unknown corpse in order to ascertain its identity. Molecular anthropologists investigate the origins and the relationships between populations through a study of DNA. The differences in DNA sequences between populations in those parts of the DNA that do not carry genetic coding are more reliable indicators of genetic relationships between populations than selective phenotypical features and the genes that affect them. Therefore, molecular anthropological research is moving away from the so-called classical indicators of cellular DNA (e.g. the comparison of blood groups) to the study of microsatellites (DNA). These so-called tandem copies comprise the majority of DNA, they are neutral with respect to selection, and they have a relatively high incidence of mutation. The DNA of the cell nucleus is used mainly in estimating the genetic distances between different populations.

Molecular anthropologists are particularly interested in mtDNA and Y-DNA because the former permits the elucidation of the origins of female ancestors and the latter of male ancestors, and consequently it is possible to reconstruct ancient migrations. The family tree of maternal lines has been reconstructed to a common original form (a mitochondrial eEve f), and that of paternal lines to their common original form (an eAdam f). Contrary to common belief, these original forms did not necessarily belong to the last common original mother and father of all human beings because mtDNA and Y-DNA are particularly susceptible to genetic drift (chance). The maternal line vanishes if the woman does not have any daughters, and the paternal line if the man has no sons.

Genetic drift is most likely to take place when a population goes through a so-called genetic bottleneck. This happens, for example, when a group becomes detached from the main population and migrates elsewhere. The descendents of these so-called efounders f have a random collection of the paternal and maternal lines in the original population. A population also passes through a genetic bottleneck when it rapidly decreases in size. In such a situation, rare maternal and paternal lines (and their nuclear DNA indicators) can easily disappear.

Although mtDNA and Y-DNA provide more information about ancient migrations because of the founder effect, nuclear DNA is a more reliable indicator of genetic relationships between peoples. This is because of the greater vulnerability of mtDNA and Y-Dna to genetic drift and also because in most communities a woman moves into the home of her husband when she marries. Neighbouring populations which have exchanged genes over many generations, but which have separate origins, typically have many of the same maternal lines and few of the same paternal lines, and the genetic distances calculated on the basis of nuclear DNA indicators show that they are genetically close to each other. Therefore the origins of peoples and the relationships between them should not be reconstructed on the basis of mtDNA alone. Molecular anthropological research will in the coming years provide more exact information about the molecular evolution of the human race and about the origins of peoples and the relationships between them. Our knowledge about Y-DNA variation in particular will increase.

Population genetics
DNA research

Table of contents: Demography, ethnicity and physical anthropology

Markku Niskanen



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