情感障礙（例如焦慮和抑郁）在全球范圍內(nèi)具有較高的發(fā)病率,，往往給病人造成心理和生活上的諸多困擾和障礙，嚴(yán)重者更會(huì)表現(xiàn)出自殺傾向,。因此,，研究情感障礙的機(jī)理顯得尤為迫切,。情感障礙具有較強(qiáng)的遺傳性,。早前的研究已經(jīng)發(fā)現(xiàn)，在高加索人（也稱白種人） 中,，編碼5-羥色胺轉(zhuǎn)運(yùn)體蛋白的5-HTTLPR基因在焦慮和抑郁的發(fā)生中至關(guān)重要,。5-HTTLPR短等位基因的存在對(duì)于白種人而言往往暗示著發(fā)生焦慮和抑郁的較大可能性。然而,，在亞洲人群中這種關(guān)聯(lián)是否存在仍是個(gè)謎,。最近,，Neuroscience Bulletin 2013年第1期的封面文章對(duì)此給出了答案。在該研究中,，來(lái)自中國(guó)科學(xué)院自動(dòng)化研究所和天津醫(yī)科大學(xué)總醫(yī)院的科學(xué)家們對(duì)233位健康的中國(guó)漢族受試者,，運(yùn)用功能磁共振成像(fMRI)和磁共振彌散張量成像(DTI)比較了5-HTTLPR長(zhǎng)、短等位基因攜帶者大腦中腦區(qū)間的功能(functional connectivity)與結(jié)構(gòu)連接(structural connectivity)的變化,。研究意外的發(fā)現(xiàn),，5-HTTLPR長(zhǎng)等位基因(L allele)攜帶者較短純合子攜帶者(S-homozygotes)具有更高的焦慮分值，并且靜息狀態(tài)下前額葉皮層—杏仁核的功能和結(jié)構(gòu)連接顯著減弱,。Pearson相關(guān)系數(shù)檢驗(yàn)顯示,，這兩個(gè)腦區(qū)間的功能連接與焦慮程度顯著負(fù)相關(guān)，并且結(jié)構(gòu)連接與抑郁程度也顯著負(fù)相關(guān),。這些結(jié)果表明,，與白種人不同，在中國(guó)漢族人群中,，5-HTTLPR的長(zhǎng)等位基因可能是焦慮或抑郁的易感基因,。因此，在抑郁/焦慮的基因相關(guān)研究及其后續(xù)可能的臨床運(yùn)用中,，應(yīng)當(dāng)考慮個(gè)體的種族背景,。
研究成果對(duì)于認(rèn)識(shí)神經(jīng)網(wǎng)絡(luò)處理情感信息的結(jié)構(gòu)和功能基礎(chǔ)有長(zhǎng)遠(yuǎn)的貢獻(xiàn)，同時(shí)也增加了人們對(duì)焦慮和抑郁病理機(jī)制的認(rèn)識(shí),。重要的是,，這些發(fā)現(xiàn)明確了基因?qū)τ谏窠?jīng)信號(hào)處理的重要性以及研究精神紊亂時(shí)考慮種族背景的重要性。此外,，對(duì)于識(shí)別易感個(gè)體以助于實(shí)現(xiàn)有效的早期干預(yù),，建立針對(duì)神經(jīng)系統(tǒng)治療方案并最終改善焦慮和抑郁等精神疾病的預(yù)后，本研究都具有推動(dòng)作用,。 （生物谷 Bioon.com）
生物谷推薦的英文摘要
Neurosci Bull doi: 10.1007/s12264-013-1302-6
The long rather than the short allele of 5-HTTLPR predisposes Han Chinese to anxiety and reduced connectivity between prefrontal cortex and amygdala
Long H, Liu B, Hou B, Wang C, Li J, Qin W, Wang D, Zhou Y, Kendrick KM, Yu C, Jiang T
The short allele of the serotonin-transporter gene is associated with higher risk for anxiety and depression in Caucasians, but this association is still unclear in Asians. Here, we addressed this issue using behavioral and multi-modal MRI approaches in a large group of healthy Han Chinese participants (n = 233). In contrast to findings in Caucasians, we found that long-allele (L) carriers had higher anxiety scores. In another group (n = 64) experiencing significant levels of depression or anxiety, the L-allele frequency was also significantly higher. In healthy participants, L-carriers had reduced functional and anatomical connectivity between the amygdala and prefrontal cortex (PFC), which was correlated with anxiety or depression scores. Our findings demonstrated that in Chinese Han participants, in contrast to Caucasians, the L-allele confers vulnerability to anxiety or depression and weakens top-down emotional control between the PFC and amygdala. Therefore, ethnic background should be taken into account in generelated studies and their potential clinical applications.
