{"id":821,"date":"2019-09-25T09:24:14","date_gmt":"2019-09-25T09:24:14","guid":{"rendered":"http:\/\/uni.hi.is\/apalsson\/?p=821"},"modified":"2019-09-25T09:24:44","modified_gmt":"2019-09-25T09:24:44","slug":"icelandic-geta-visindin-sagt-mer-hversu-mikill-neanderdalsmadur-eg-er","status":"publish","type":"post","link":"https:\/\/uni.hi.is\/apalsson\/IS\/2019\/09\/25\/icelandic-geta-visindin-sagt-mer-hversu-mikill-neanderdalsmadur-eg-er\/","title":{"rendered":"Geta v\u00edsindin sagt m\u00e9r hversu mikill neanderdalsma\u00f0ur \u00e9g er?"},"content":{"rendered":"

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N\u00fdlegt svar fyrir v\u00edsindavefinn. Arnar P\u00e1lsson. \u201eGeta v\u00edsindin sagt m\u00e9r hversu mikill neanderdalsma\u00f0ur \u00e9g er?<\/a>\u201c V\u00edsindavefurinn<\/i>, 18. september 2019.<\/section>\n
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\u00d6ll spurningin hlj\u00f3\u00f0a\u00f0i svona:<\/p>\n

Geta v\u00edsindin sagt m\u00e9r hversu mikill neanderdalsma\u00f0ur \u00e9g er og hva\u00f0a merkingu \u00fea\u00f0 hefur a\u00f0 hafa erf\u00f0aefni fr\u00e1 neanderdalsm\u00f6nnum \u00ed s\u00e9r?<\/p><\/blockquote>\n

Homo sapiens<\/a><\/em> er komin af st\u00f3rri fj\u00f6lskyldu manntegunda sem skildust fr\u00e1 sameiginlegum forf\u00f6\u00f0ur okkar og simpansa <\/a> fyrir fj\u00f3rum til fimm millj\u00f3num \u00e1ra. Flestar manntegundirnar bjuggu \u00ed Afr\u00edku en dreif\u00f0ust einnig um gamla heiminn, og er tali\u00f0 a\u00f0 \u00e1 hverjum t\u00edma hafi veri\u00f0 til nokkrar \u00f3l\u00edkar manntegundir. N\u00fdlegar ranns\u00f3knir \u00e1 fornerf\u00f0aefni (e. ancient DNA) sem greinst hefur \u00ed tug\u00fe\u00fasund \u00e1ra g\u00f6mlum beinum gera stofnerf\u00f0afr\u00e6\u00f0ingum kleift a\u00f0 greina skyldleika n\u00fat\u00edmamannsins og annara h\u00f3pa manna sem uppi voru \u00e1 s\u00ed\u00f0ustu 100.000 \u00e1rum og einnig a\u00f0 greina erf\u00f0abl\u00f6ndun milli h\u00f3pa.<\/p>\n

Ein \u00feessara manntegunda er Homo neanderthalensis<\/a><\/em> sem lif\u00f0i \u00ed Evr\u00f3pu og As\u00edu en d\u00f3 \u00fat fyrir um 30.000 \u00e1rum. Bylting \u00ed ra\u00f0greiningu<\/a> erf\u00f0amengja og b\u00e6ttar a\u00f0fer\u00f0ir vi\u00f0 einangrun \u00e1 erf\u00f0aefni<\/a> \u00far beinaleifum ger\u00f0u \u00fea\u00f0 m\u00f6gulegt a\u00f0 ra\u00f0greina litning<\/a> hvatbera<\/a> \u00far t\u00f6nn neanderdalsmanns (Krings o.fl. 1997). Ni\u00f0urst\u00f6\u00f0ur s\u00fdndu a\u00f0 H. Neanderthalensis<\/em> var \u00e6ttingi n\u00fat\u00edmamannsins og a\u00f0 vi\u00f0 \u00e1ttum sameiginlegan forf\u00f6\u00f0ur fyrir um 500.000-700.000 \u00e1rum. En hvatberinn ber einungis l\u00edtinn hluta erf\u00f0aefnis einstaklings. \u00c1ri\u00f0 2010 birtust ni\u00f0urst\u00f6\u00f0ur \u00far ra\u00f0greiningu erf\u00f0amengja um 38.000 \u00e1ra gamalla beina \u00feriggja neanderdalsmanna \u00far Vindija-hellinum \u00ed Kr\u00f3at\u00edu. \u00de\u00e6r sta\u00f0festu mati\u00f0 \u00e1 aldri sameiginlegs forf\u00f6\u00f0ur neanderdalsmanna og okkar. Mest sl\u00e1andi var hins vegar s\u00fa sta\u00f0reynd a\u00f0 sumir menn eru me\u00f0 litningahluta sem svipar mj\u00f6g sterklega til erf\u00f0amengis neanderdalsmannanna. \u00dea\u00f0 \u00fe\u00fd\u00f0ir a\u00f0 sum gen<\/a> og litningab\u00fatar hafa flust \u00e1 milli tegundanna, inn \u00ed erf\u00f0amengi forfe\u00f0ra okkar. Sl\u00edkt gerist me\u00f0 \u00e6xlun og kynbl\u00f6ndun. Athyglisvert er a\u00f0 gen \u00e6ttu\u00f0 \u00far neanderdalsm\u00f6nnum finnast eing\u00f6ngu \u00ed m\u00f6nnum sem eru fr\u00e1 landsv\u00e6\u00f0um utan Afr\u00edku. Neanderdalsmenn bjuggu einmitt \u00ed Evras\u00edu og hafa l\u00edklega blandast m\u00f6nnum sem bjuggu utan Afr\u00edku fyrir um \u00fea\u00f0 bil 47.000 til 65.000 \u00e1rum. Greiningar \u00e1 erf\u00f0aefni \u00ed fornum mannabeinum hafa l\u00edka s\u00fdnt a\u00f0 \u00e1 svipu\u00f0um t\u00edma var uppi \u00f6nnur tegund manna austar \u00ed As\u00edu. \u00deeir hafa veri\u00f0 nefndir denisovamenn, eftir Denisova-hellinum \u00ed Altai-fj\u00f6llunum \u00fear sem fyrstu beinin fundust. \u00deeir voru \u00e1l\u00edka skyldir m\u00f6nnum og neanderdalsmenn og komi\u00f0 hefur \u00ed lj\u00f3s a\u00f0 \u00feeir \u00e6xlu\u00f0ust einnig vi\u00f0 forfe\u00f0ur okkar. En hversu miki\u00f0 af erf\u00f0aefni kom fr\u00e1 \u00feessum \u00e6ttingjum okkar? A\u00f0 me\u00f0altali er um 2% af erf\u00f0aefni f\u00f3lks utan Afr\u00edku \u00e6tta\u00f0 fr\u00e1 neanderdalsm\u00f6nnum. Gen fr\u00e1 denisovam\u00f6nnum finnast \u00e1 heldur afmarka\u00f0ra sv\u00e6\u00f0i, alls ekki \u00ed f\u00f3lki fr\u00e1 Afr\u00edku og Evr\u00f3pu en umtalsvert \u00ed frumbyggjum austur As\u00edu. H\u00e6st er hlutfalli\u00f0 \u00e1 Pap\u00faa N\u00fdju-G\u00edneu, um 8%. Erf\u00f0aefni\u00f0 fr\u00e1 \u00feessum \u00e6ttingjum okkar er ekki jafndreift um erf\u00f0amengi\u00f0. Um 50% af erf\u00f0amenginu s\u00fdnir engar v\u00edsbendingar um genafl\u00e6\u00f0i fr\u00e1 neanderdalsm\u00f6nnum. \u00dear me\u00f0 tali\u00f0 X-litningurinn allur og m\u00f6rg gen annar sta\u00f0ar \u00ed erf\u00f0amenginu. \u00deetta bendir til \u00feess a\u00f0 sams\u00e6tur gena \u00far neanderdalsm\u00f6nnum hafi ekki passa\u00f0 s\u00e9rstaklega vel vi\u00f0 erf\u00f0amengi forfe\u00f0ra okkar. \u00c1 m\u00f3ti kemur a\u00f0 sams\u00e6tur sumra gena fr\u00e1 \u00feeim hafa n\u00e1\u00f0 50% t\u00ed\u00f0ni me\u00f0al manna utan Afr\u00edku. A\u00f0 s\u00ed\u00f0ustu, \u00fear sem neanderdals- og denisovamenn voru uppi \u00e1 saman t\u00edma var bl\u00f6ndun \u00feeirra einnig m\u00f6guleg. \u00deetta var sta\u00f0fest \u00e1ri\u00f0 2018 \u00feegar ra\u00f0greint var erf\u00f0aefni beins ungrar st\u00falku sem \u00e1tti neanderdalsmann a\u00f0 f\u00f6\u00f0ur og denisovakonu sem m\u00f3\u00f0ur. Denny (svo nefnd af erf\u00f0afr\u00e6\u00f0ingunum) var fyrstu kynsl\u00f3\u00f0ar blendingur \u00feessara tveggja manntegunda e\u00f0a undirtegunda.<\/p>\n

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L\u00edk\u00f6n um skyldleika neanderdalsmanna (N), Evr\u00f3pub\u00faa (E) og Afr\u00edkumanna (Y). T\u00edma\u00e1s rennur fr\u00e1 efri hluta mynda ni\u00f0ur \u00e1 greinar. Efst tengjast h\u00f3parnir vegna sameiginlegs uppruna, en s\u00ed\u00f0an a\u00f0skiljast \u00feeir \u00feegar \u00fer\u00f3uninni vindur \u00e1fram. \u00deykkt greina v\u00edsar \u00ed stofnst\u00e6r\u00f0, til d\u00e6mis \u00ferengist grein Evr\u00f3pub\u00faanna eftir a\u00f0 \u00feeir skildust fr\u00e1 afr\u00edsku greininni. L\u00edkan A s\u00fdnir einfaldan a\u00f0skilna\u00f0 h\u00f3panna, me\u00f0 fl\u00f6skuh\u00e1ls \u00ed stofnst\u00e6r\u00f0 forfe\u00f0ra Evr\u00f3pub\u00faa. L\u00edkan B s\u00fdnir flutning erf\u00f0aefnis fr\u00e1 neanderdalsm\u00f6nnum \u00ed Evr\u00f3pub\u00faana. L\u00edkan C s\u00fdnir enga erf\u00f0abl\u00f6ndun, en punktal\u00ednan t\u00e1knar a\u00f0 eldri a\u00f0greining hafi veri\u00f0 \u00ed forf\u00f6\u00f0ur manna og neanderdalsmanna og s\u00fa a\u00f0greining hafi leitt til munar \u00e1 f\u00f3lki innan og utan Afr\u00edku. L\u00edkan B er best stutt g\u00f6gnunum. Yaruba-\u00e6ttb\u00e1lkurinn \u00ed N\u00edger\u00edu er fulltr\u00fai afr\u00edska h\u00f3psins og evr\u00f3pski h\u00f3purinn er blanda af evr\u00f3pskum landnemum \u00ed Amer\u00edku. G\u00f6gn um neanderdalsmennina komu \u00far ra\u00f0greiningum \u00e1 beinas\u00fdnum fr\u00e1 Evr\u00f3pu. Mynd er einf\u00f6ldu\u00f0 eftir grein Sankararaman o.fl. 2012.<\/p>\n<\/div>\n<\/div>\n

Me\u00f0 \u00fev\u00ed a\u00f0 gera erf\u00f0agreiningu \u00e1 einstaklingum me\u00f0 hundru\u00f0um \u00fe\u00fasunda erf\u00f0amarka er h\u00e6gt a\u00f0 meta hversu h\u00e1tt hlutfall erf\u00f0aefnis \u00feeirra er \u00e6tta\u00f0 fr\u00e1 neanderdals- e\u00f0a denisovam\u00f6nnum. Fyrirt\u00e6ki sem bj\u00f3\u00f0a upp \u00e1 arfger\u00f0argreiningar til a\u00f0 meta uppruna einstaklinga meta m\u00f6rg hver einnig erf\u00f0aframlag \u00feessara h\u00f3pa. Svari\u00f0 vi\u00f0 spurningunni, get \u00e9g fari\u00f0 \u00ed erf\u00f0apr\u00f3f sem s\u00fdnir hversu mikill neanderdalsma\u00f0ur \u00e9g er, er \u00fev\u00ed j\u00e1. H\u00e6gt er a\u00f0 fara \u00ed erf\u00f0apr\u00f3f og meta hversu st\u00f3r hluti erf\u00f0aefnis vi\u00f0komandi er komi\u00f0 fr\u00e1 neanderdalsm\u00f6nnum. L\u00edklegast er a\u00f0 um 1,5 til 2% af erf\u00f0aefni vi\u00f0komandi s\u00e9 \u00e6tta\u00f0 \u00far neanderdalsm\u00f6nnum. En hvernig \u00e1 a\u00f0 t\u00falka svona pr\u00f3f? \u00dea\u00f0 a\u00f0 ein manneskja s\u00e9 me\u00f0 meira af neanderdalsgenum en \u00f6nnur \u00fe\u00fd\u00f0ir ekki a\u00f0 ein s\u00e9 \u00fer\u00f3a\u00f0ri (e\u00f0a \u00e6\u00f0ri) en hin. Ef einhver myndi t\u00falka gen fr\u00e1 neanderdals- e\u00f0a denisovam\u00f6nnum sem mengun \u00fe\u00e1 teljast afr\u00edskir h\u00f3par hreinr\u00e6kta\u00f0astir me\u00f0al manna. En sl\u00edk \u00e1lyktun er ekki \u00e1 r\u00f6kum reist \u00fev\u00ed tegundirnar voru jafngildar me\u00f0an \u00fe\u00e6r lif\u00f0u \u00e1 j\u00f6r\u00f0inni. Sams\u00e6tur vissra gena fr\u00e1 neanderdalsm\u00f6nnum hafa veri\u00f0 bendla\u00f0ar vi\u00f0 vissa eiginleika, til d\u00e6mis \u00feol gagnvart vissum sj\u00fakd\u00f3mum. Merkilegasta framlagi\u00f0 fr\u00e1 \u00feessum tegundum er samt sams\u00e6ta \u00e1kve\u00f0ins gens sem gerir T\u00edbetb\u00faum kleift a\u00f0 lifa h\u00e1tt \u00ed fj\u00f6llum. S\u00fa sams\u00e6ta er \u00e6ttu\u00f0 fr\u00e1 denisovam\u00f6nnum. Samantekt:<\/strong><\/p>\n