{"id":618,"date":"2017-01-04T14:19:04","date_gmt":"2017-01-04T14:19:04","guid":{"rendered":"http:\/\/uni.hi.is\/apalsson\/?p=618"},"modified":"2017-01-04T14:19:04","modified_gmt":"2017-01-04T14:19:04","slug":"icelandic-hafa-nutimalaeknavisindi-gert-okkur-onaem-fyrir-logmalum-darwins","status":"publish","type":"post","link":"https:\/\/uni.hi.is\/apalsson\/IS\/2017\/01\/04\/icelandic-hafa-nutimalaeknavisindi-gert-okkur-onaem-fyrir-logmalum-darwins\/","title":{"rendered":"Hafa n\u00fat\u00edmal\u00e6knav\u00edsindi gert okkur \u00f3n\u00e6m fyrir l\u00f6gm\u00e1lum Darwins?"},"content":{"rendered":"

Svara\u00f0 fyrir v\u00edsindavef H\u00e1sk\u00f3la \u00cdslands. \u00cd heild hlj\u00f3\u00f0a\u00f0i spurningin til v\u00edsindavefsins svona:<\/p>\n

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Hafa n\u00fat\u00edmal\u00e6knav\u00edsindi gert okkur \u00f3n\u00e6m fyrir l\u00f6gm\u00e1lum \u00fer\u00f3unarkenningar Darwins um a\u00f0 s\u00e1 h\u00e6fasti lifir? \u00cd dag lifa margir sem hef\u00f0u d\u00e1i\u00f0 af n\u00e1tt\u00farulegum s\u00f6kum \u00e1\u00f0ur.<\/a><\/p><\/blockquote>\n<\/div>\n

Til a\u00f0 svara spurningunni \u00feurfum vi\u00f0 a\u00f0 kynna nokkrar sta\u00f0reyndir. S\u00fa fyrsta er n\u00e1tt\u00farulegt val sem er, \u00e1samt hugmyndinni um \u00fer\u00f3unartr\u00e9 og stofna, lykilatri\u00f0i \u00ed \u00fer\u00f3unarkenningu<\/a> Darwins<\/a>. N\u00e1tt\u00farulegt val er aflei\u00f0ing \u00feess a\u00f0:<\/p>\n

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i) einstaklingar \u00ed stofni eru \u00f3l\u00edkir<\/p><\/blockquote>\n<\/div>\n

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ii) breytileikinn \u00e1 milli \u00feeirra er arfgengur (a\u00f0 hluta a\u00f0 minnsta kosti)<\/p>\n

iii) einstaklingar eignast mism\u00f6rg afkv\u00e6mi.<\/p>\n<\/blockquote>\n<\/div>\n

Af \u00feessum \u00e1st\u00e6\u00f0um veljast vissar ger\u00f0ir einstaklinga fram yfir a\u00f0rar, alveg n\u00e1tt\u00farulega. Og vegna \u00feess a\u00f0 bar\u00e1tta er fyrir l\u00edfinu, ekki komast allir einstaklingar \u00e1 legg e\u00f0a eignast afkv\u00e6mi, mun n\u00e1tt\u00farulegt val lei\u00f0a til a\u00f0l\u00f6gunar l\u00edfvera.<\/p>\n

\u00d6nnur sta\u00f0reyndin er s\u00fa a\u00f0 n\u00e1tt\u00farulegt val er af tveimur megin ger\u00f0um. J\u00e1kv\u00e6tt val stu\u00f0lar a\u00f0 betrumb\u00f3tum \u00e1 l\u00edfverum og a\u00f0lagar \u00fe\u00e6r a\u00f0 breytilegu umhverfi. \u00c1 hinn b\u00f3ginn fjarl\u00e6gir hreinsandi val ska\u00f0legar st\u00f6kkbreytingar<\/a> e\u00f0a \u00f3h\u00e6fari ger\u00f0ir. Fyrir \u00feessa spurningu skiptir hreinsandi val meira m\u00e1li.<\/div>\n

\u00deri\u00f0ja sta\u00f0reyndin er s\u00fa a\u00f0 st\u00f6kkbreytingar eru algengar \u00ed stofnum l\u00edfvera, l\u00edka mannsins. St\u00f6kkbreytingar falla \u00ed \u00ferj\u00e1 meginflokka me\u00f0 tilliti til \u00e1hrifa \u00e1 h\u00e6fni einstaklinga. F\u00e1t\u00ed\u00f0astar eru breytingar sem betrumb\u00e6ta l\u00edfverur (\u00fe\u00e6r eru hr\u00e1efni j\u00e1kv\u00e6\u00f0s vals sem stu\u00f0lar a\u00f0 \u00fev\u00ed a\u00f0 t\u00ed\u00f0ni \u00feeirra eykst \u00ed stofninum). Algengast er a\u00f0 st\u00f6kkbreytingar sem finnast \u00ed stofnum s\u00e9u hlutlausar, hafi engin \u00e1hrif \u00e1 h\u00e6fni einstaklinga, til a\u00f0 mynda l\u00edfsl\u00edkur e\u00f0a frj\u00f3semi. \u00deri\u00f0ji flokkurinn eru breytingar sem draga \u00far h\u00e6fni, sker\u00f0a l\u00edfsl\u00edkur e\u00f0a frj\u00f3semi einstaklinga. Hreinsandi val virkar \u00e1 \u00fe\u00e6r \u00e1 \u00feann h\u00e1tt a\u00f0 ef breytingin er mj\u00f6g ska\u00f0leg \u00fe\u00e1 getur h\u00fan ekki or\u00f0i\u00f0 algeng \u00ed stofninum. Ska\u00f0legar st\u00f6kkbreytingar geta dulist hreinsandi vali \u00e1 tvo vegu, ef \u00e1hrif \u00feeirra eru v\u00edkjandi<\/a> e\u00f0a ef \u00e1hrifin birtast bara vi\u00f0 \u00e1kve\u00f0nar umhverfisa\u00f0st\u00e6\u00f0ur. Af \u00feessum ors\u00f6kum finnast \u00ed \u00f6llum stofnum margar f\u00e1t\u00ed\u00f0ar ska\u00f0legar breytingar, svo k\u00f6llu\u00f0 erf\u00f0abyr\u00f0i.<\/p>\n

Vi\u00f0 getum \u00fev\u00ed umor\u00f0a\u00f0 spurninguna \u00e1 eftirfarandi h\u00e1tt:<\/p>\n

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Hafa l\u00e6knav\u00edsindin dregi\u00f0 \u00far styrk hreinsandi n\u00e1tt\u00farlegs val vegna \u00feess a\u00f0 \u00ed dag geta einstaklingar lifa\u00f0 og \u00e6xlast sem fyrir tveimur \u00f6ldum e\u00f0a hundra\u00f0 \u00fe\u00fasund \u00e1rum hef\u00f0u ekki komist \u00e1 legg?<\/p><\/blockquote>\n<\/div>\n

\u00dea\u00f0 er r\u00e9tt a\u00f0 sumar st\u00f6kkbreytingar sem \u00e1\u00f0ur dr\u00f3gu f\u00f3lk til dau\u00f0a eru ekki banv\u00e6nar \u00ed dag. Me\u00f0 \u00feekkingu okkar \u00e1 e\u00f0li sj\u00fakd\u00f3ma breytum vi\u00f0 umhverfi genanna<\/a>. \u00dea\u00f0 gerum vi\u00f0 til d\u00e6mis me\u00f0 \u00fev\u00ed a\u00f0 snei\u00f0a hj\u00e1 \u00fatfj\u00f3lubl\u00e1um geislum<\/a> ef vi\u00f0 erum me\u00f0 galla \u00ed DNA<\/a> vi\u00f0ger\u00f0argenum e\u00f0a for\u00f0ast am\u00edn\u00f3s\u00fdruna<\/a> fen\u00fdlalan\u00edn \u00ed f\u00e6\u00f0u ef vi\u00f0 erum me\u00f0 PKU<\/a>-efnaskiptasj\u00fakd\u00f3m. \u00cd \u00f6\u00f0rum tilfellum, til d\u00e6mis ef um mikla l\u00edkamlega galla er a\u00f0 r\u00e6\u00f0a, geta l\u00e6knav\u00edsindin gert sumum kleift a\u00f0 lifa \u00e1g\u00e6tu l\u00edfi og jafnvel eignast afkv\u00e6mi. \u00deetta \u00e1 a\u00f0 minnsta kosti vi\u00f0 \u00e1 Vesturl\u00f6ndum en g\u00e6\u00f0um l\u00e6knav\u00edsinda er misdreift \u00e1 j\u00f6r\u00f0inni eftir landsv\u00e6\u00f0um og efnahag.<\/p>\n

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Dreyras\u00fdki er arfgengur bl\u00e6\u00f0ingarsj\u00fakd\u00f3mur. L\u00edfsl\u00edkur bl\u00e6\u00f0ara hafa breyst miki\u00f0 me\u00f0 framf\u00f6rum \u00ed l\u00e6knav\u00edsindum. Me\u00f0 \u00fev\u00ed a\u00f0 veita sj\u00faklingi vi\u00f0eigandi me\u00f0fer\u00f0 fr\u00e1 unga aldri er h\u00e6gt a\u00f0 draga verulega \u00far einkennunum \u00feannig a\u00f0 l\u00edfsst\u00edll ver\u00f0i n\u00e1nast e\u00f0lilegur og \u00e6vilengd svipu\u00f0 og hj\u00e1 heilbrig\u00f0um.<\/p>\n<\/div>\n<\/div>\n

Erf\u00f0afr\u00e6\u00f0ingar s\u00ed\u00f0ustu aldar h\u00f6f\u00f0u \u00e1huga \u00e1 \u00feessari spurningu og notu\u00f0u j\u00f6fnur stofnerf\u00f0afr\u00e6\u00f0i til a\u00f0 sko\u00f0a samspil nokkurra st\u00e6r\u00f0a, st\u00f6kkbreytit\u00ed\u00f0ni, styrk hreinsandi vals og \u00e1hrif hendingar \u00ed stofnum. St\u00f6kkbreytit\u00ed\u00f0ni \u00ed erf\u00f0amengi<\/a> mannsins er um 12,8 \u00d7 10-9<\/sup> \u00e1 hvern basa \u00ed hverri kynsl\u00f3\u00f0. \u00cd hverri kynfrumu eru mismargar n\u00fdjar st\u00f6kkbreytingar, fj\u00f6ldinn er oftast \u00e1 bilinu 20-100. H\u00e6gt er a\u00f0 meta stofnst\u00e6r\u00f0 mannsins fr\u00e1 stofnerf\u00f0afr\u00e6\u00f0ilegum g\u00f6gnum, og s\u00ed\u00f0an setja inn \u00ed j\u00f6fnur til a\u00f0 meta samspil \u00fe\u00e1ttanna. Me\u00f0 j\u00f6fnur stofnerf\u00f0afr\u00e6\u00f0i a\u00f0 vopni er h\u00e6gt a\u00f0 spyrja hva\u00f0 gerist ef n\u00e1tt\u00farulegt val er aftengt. \u00c1ri\u00f0 2010 reikna\u00f0i Michael Lynch \u00fat a\u00f0 \u00e1hrif upps\u00f6fnunar ska\u00f0legra breytinga v\u00e6ri 1-3% minni h\u00e6fni \u00ed hverri kynsl\u00f3\u00f0. Hann bendir \u00e1 a\u00f0 sl\u00edk upps\u00f6fnun s\u00e9 ekki alvarleg \u00feegar liti\u00f0 s\u00e9 til n\u00e6stu kynsl\u00f3\u00f0a en geti haft veruleg \u00e1hrif eftir nokkrar aldir.<\/p>\n

Stefnir mannkyni\u00f0 \u00fe\u00e1 hra\u00f0byri a\u00f0 erf\u00f0afr\u00e6\u00f0ilegri endast\u00f6\u00f0? Ekki endilega og kemur \u00fear fernt til.<\/p>\n

\u00cd fyrsta lagi er hreinsandi n\u00e1tt\u00farulegt val enn\u00fe\u00e1 virkt me\u00f0al Vesturlandab\u00faa. \u00dea\u00f0 birtist me\u00f0al annars \u00ed umtalsver\u00f0ri t\u00ed\u00f0ni k\u00edmbla\u00f0ra sem ekki \u00feroskast e\u00f0lilega og f\u00f3sturl\u00e1ta.<\/p>\n

\u00cd \u00f6\u00f0ru lagi er h\u00e6fni arfger\u00f0a tengd umhverfi. Ef breytingar ver\u00f0a \u00e1 umhverfi getur st\u00f6kkbreyting sem var hlutlaus or\u00f0i\u00f0 ska\u00f0leg, og \u00fea\u00f0 sem var ska\u00f0legt getur or\u00f0i\u00f0 hlutlaust. Ef l\u00e6knav\u00edsindum fleytir fram og almenn heg\u00f0an og atl\u00e6ti batnar, \u00fe\u00e1 \u00e6ttum vi\u00f0 a\u00f0 geta m\u00f3ta\u00f0 umhverfi\u00f0 \u00feannig a\u00f0 \u00fea\u00f0 henti genum okkar betur. Umhverfi afkomenda okkar eftir 10 kynsl\u00f3\u00f0ir ver\u00f0ur l\u00edklega anna\u00f0 (og vonandi betra) en \u00fea\u00f0 sem vi\u00f0 b\u00faum vi\u00f0.<\/p>\n

\u00cd \u00feri\u00f0ja lagi bendir allt til a\u00f0 hreinsandi val fjarl\u00e6gi margar ska\u00f0legar breytingar \u00ed einu. Samkv\u00e6mt \u00feessu hefur f\u00f3stur me\u00f0 margar ska\u00f0legar st\u00f6kkbreytingar mj\u00f6g litla h\u00e6fni \u00fev\u00ed a\u00f0 \u00e1hrif breytinganna magnast upp (me\u00f0 \u00f6\u00f0rum or\u00f0um, \u00e1hrifin leggjast ekki saman heldur margfaldast).<\/p>\n

\u00cd fj\u00f3r\u00f0a lagi er h\u00e6gt a\u00f0 sj\u00e1 fyrir s\u00e9r auki\u00f0 hlutverk fyrir erf\u00f0askimanir \u00e1 f\u00f3strum e\u00f0a foreldrum. \u00deetta v\u00e6ri \u00ed raun framhald af skimunum<\/a> sem n\u00fa eru ger\u00f0ar fyrir \u00fer\u00edst\u00e6\u00f0u \u00e1 litningi 21 sem veldur Downs<\/a>-heilkenni og nokkrum erf\u00f0ag\u00f6llum me\u00f0 sterk \u00e1hrif. H\u00e9r ver\u00f0um vi\u00f0 \u00fe\u00f3 a\u00f0 st\u00edga afar varlega til jar\u00f0ar \u00fev\u00ed svipa\u00f0ar hugmyndir voru kveikjan a\u00f0 mannkynb\u00f3tastefnunni (e. Eugenics) sem margar \u00fej\u00f3\u00f0ir \u00e1 Vesturl\u00f6ndum og \u00ed Amer\u00edku a\u00f0hylltust og \u00fatf\u00e6r\u00f0u hro\u00f0alega. Jafnvel mildari \u00fatg\u00e1fur \u00e1 Nor\u00f0url\u00f6ndum voru harkalegar, geldingar og h\u00e6lisvistun undirm\u00e1lsf\u00f3lks, og \u00fea\u00f0 \u00fearf vonandi ekki a\u00f0 rifja upp markvissa \u00e6xlun ar\u00eda og \u00f6rl\u00f6g gy\u00f0inga og s\u00edgauna \u00ed \u00fatr\u00fdmingarb\u00fa\u00f0um<\/a> \u00ed \u00feri\u00f0ja r\u00edkinu.<\/p>\n

Samantekt<\/strong><\/p>\n