根據(jù)一項新的報告,，一個人對于預(yù)料到和收到一份獎賞的反應(yīng)可能受到遺傳因素的影響,。這些結(jié)果提示,，遺傳變異可能對尋求獎賞行為的個體差異有貢獻(xiàn)，而且可能對一個人的神經(jīng)精神疾病易感性有貢獻(xiàn),。
利用功能磁共振成像（fMRI）技術(shù),，Karen Berman及其同事發(fā)現(xiàn)，多巴胺傳遞的差異很可能調(diào)控著涉及到獎賞的預(yù)期與接受的人類大腦區(qū)域的反應(yīng),。在fMRI大腦掃描中,，這組科學(xué)家發(fā)現(xiàn)攜帶導(dǎo)致突觸中有更多多巴胺的特定多巴胺變異的人們在預(yù)料到獎賞以及獲得獎賞的時候表現(xiàn)出了神經(jīng)活化增加。各種神經(jīng)精神疾病,，例如帕金森氏癥,、精神分裂癥、毒品成癮以及抑郁癥也與多巴胺系統(tǒng)的功能障礙有聯(lián)系,。這組作者提出,，多巴胺轉(zhuǎn)運(yùn)體類型的遺傳變異可能導(dǎo)致多巴胺再吸收的下降，并最終導(dǎo)致大腦神經(jīng)突觸有更多的多巴胺,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS December 22, 2008, doi: 10.1073/pnas.0805517106
Variation in dopamine genes influences responsivity of the human reward system
Jean-Claude Drehera,1,2, Philip Kohna,b, Bhaskar Kolachanab, Daniel R. Weinbergerb, and Karen Faith Bermana,b,2
aSection on Integrative Neuroimaging,
bGenes, Cognition and Psychosis Program, National Institute of Mental Health, Bethesda, MD 20892-1365
In humans, dopamine neurotransmission is influenced by functional polymorphisms in the dopamine transporter (DAT1) and catechol-O-methyltransferase (COMT) genes. Here, we used event-related functional magnetic resonance imaging to directly investigate the neurofunctional effects of the Val158Met COMT and variable number of tandem repeat DAT1 polymorphisms on distinct components of the reward system in humans. The results revealed a main effect of COMT genotype in the ventral striatum and lateral prefrontal cortex during reward anticipation (P < 0.001, uncorrected) and in the orbitofrontal cortex at the time of reward delivery (P < 0.005), met/met individuals exhibiting the highest activation. The main effect of DAT1 genotype was seen in robust blood-oxygen-level-dependent response differences in the caudate nucleus and ventral striatum during reward anticipation (P < 0.001) and in the lateral prefrontal cortex and midbrain at the time of reward delivery, with carriers of the DAT1 9-repeat allele showing the highest activity. Moreover, an interaction between the COMT and DAT1 genes was found in the ventral striatum and lateral prefrontal cortex during reward anticipation and in the lateral prefrontal and orbitofrontal cortices as well as in the midbrain at the time of reward delivery, with carriers of the DAT1 9-repeat allele and COMT met/met allele exhibiting the highest activation, presumably reflecting functional change consequent to higher synaptic dopamine availability. Taken together, these results indicate that genetically influenced variations in dopamine transmission modulate the response of brain regions involved in anticipation and reception of rewards and suggest that these responses may contribute to individual differences in reward-seeking behavior and in predisposition to neuropsychiatric disorders.
