英國研究人員發(fā)現(xiàn),，使人類能夠思考和推理的基因開始進(jìn)化于5億年前。從這一刻起,，人類擁有了學(xué)習(xí)復(fù)雜技能,、分析形勢、靈活思考的能力,。發(fā)表在《自然·神經(jīng)科學(xué)》上的此項(xiàng)研究成果,，同時(shí)也揭示出行為進(jìn)化和腦部疾病起源之間的直接聯(lián)系。
科學(xué)家們認(rèn)為,，為提高我們的心智能力做出貢獻(xiàn)的相同基因,，也要為某些腦部疾病的形成負(fù)上責(zé)任。該研究表明,，人類智力的形成,，是人類祖先大腦基因數(shù)量增長的結(jié)果。生活在5億年前的一種簡單無脊椎動(dòng)物經(jīng)歷了一場“遺傳事故”,，導(dǎo)致形成了這些基因的額外副本,。這種動(dòng)物的后代受益于這些額外的基因，最終導(dǎo)致了包括人類在內(nèi)的行為復(fù)雜的脊椎動(dòng)物的出現(xiàn),。
該研究小組使用比較任務(wù)法研究了小鼠和人類的心智能力,，具體涉及識(shí)別觸摸屏電腦上的物體。然后,，研究人員將這些行為測試的結(jié)果,，與各種行為進(jìn)化時(shí)不同物種的遺傳密碼信息結(jié)合起來。他們發(fā)現(xiàn),，更高的心智功能在人類和小鼠身上均受控于相同的基因,。
研究還表明，當(dāng)這些基因發(fā)生突變或損壞時(shí),，它們會(huì)削弱更高的心智功能,。更高的智力和更復(fù)雜的行為導(dǎo)致了更多的精神疾病,。（生物谷Bioon.com）
doi: 10.1038/nn.3276.
PMC:
PMID:
Synaptic scaffold evolution generated components of vertebrate cognitive complexity
Nithianantharajah J, Komiyama NH, McKechanie A, Johnstone M, Blackwood DH, Clair DS, Emes RD, van de Lagemaat LN, Saksida LM, Bussey TJ, Grant SG.
The origins and evolution of higher cognitive functions, including complex forms of learning, attention and executive functions, are unknown. A potential mechanism driving the evolution of vertebrate cognition early in the vertebrate lineage (550 million years ago) was genome duplication and subsequent diversification of postsynaptic genes. Here we report, to our knowledge, the first genetic analysis of a vertebrate gene family in cognitive functions measured using computerized touchscreens. Comparison of mice carrying mutations in each of the four Dlg paralogs showed that simple associative learning required Dlg4, whereas Dlg2 and Dlg3 diversified to have opposing functions in complex cognitive processes. Exploiting the translational utility of touchscreens in humans and mice, testing Dlg2 mutations in both species showed that Dlg2's role in complex learning, cognitive flexibility and attention has been highly conserved over 100 million years. Dlg-family mutations underlie psychiatric disorders, suggesting that genome evolution expanded the complexity of vertebrate cognition at the cost of susceptibility to mental illness.
