生物谷：据英国《每日邮报》报道，近日科学家们发现了导致人类左撇子的基因。该基因更易引发精神分裂症。
牛津大学的研究小组日前表示，携带LRRTM1基因的人们左撇子居多，因为该基因对大脑平衡能产生一定的影响。这是科学家首次发现的控制左撇子右撇子的基因。
研究发现，通常右利手的人大脑仅左半球功能较发达，具有处理语言的能力。而左撇子多用左肢，右半脑接受的刺激相对多一些，使左撇子带有右脑思维的倾向。科学家认为这是由LRRTM1基因所致。
同时，科学家还认为该基因能改善大脑左右半球不协调功能。而携带携带LRRTM1基因的人们更易患上精神分裂症。全球大约有1%人口因为大脑左右半球不协调和用左右手习惯而有精神分裂倾向。Clyde Francks博士说，这项研究希望能找出LRRTM1基因影响大脑发育的真正原因。“大脑功能性不对称在精神病学史的一个基本特征。”
这项研究小组是由来自全球20个研究中心的40名科学家组成。该研究成果发表在《分子精神病学》杂志(Molecular Psychiatry) 上。（搜狐科学）
原始出处:
Molecular Psychiatry advance online publication 31 July 2007; doi: 10.1038/sj.mp.4002053
LRRTM1 on chromosome 2p12 is a maternally suppressed gene that is associated paternally with handedness and schizophrenia
C Francks1,2, S Maegawa3,21, J Laurén4,21, B S Abrahams5, A Velayos-Baeza1, S E Medland6,7, S Colella1, M Groszer1, E Z McAuley1, T M Caffrey1, T Timmusk8, P Pruunsild8, I Koppel8, P A Lind7, N Matsumoto-Itaba9, J Nicod1, L Xiong10, R Joober11, W Enard12, B Krinsky12, E Nanba3, A J Richardson13, B P Riley5, N G Martin6, S M Strittmatter4, H-J Möller14, D Rujescu14, D St Clair15, P Muglia2, J L Roos16, S E Fisher1, R Wade-Martins1, G A Rouleau10, J F Stein13, M Karayiorgou17, D H Geschwind5, J Ragoussis1, K S Kendler5, M S Airaksinen18, M Oshimura9, L E DeLisi19,20 and A P Monaco1
1Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
2GlaxoSmithKline SpA, Research Centre, Verona, Italy
3Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University, Yonago, Tottori, Japan
4Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
5Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA
6Virginia Institute for Psychiatric and Behavioral Genetics, Department of Human Genetics, Virginia Commonwealth University, Richmond, VA, USA
7Queensland Institute of Medical Research, Brisbane, QLD, Australia
8Department of Gene Technology, Tallinn University of Technology, Tallinn, Estonia
9Department of Biomedical Science, Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Yonago, Tottori, Japan
10Center for the Study of Brain Diseases, CHUM Research Center, Montreal University, Montreal, QC, Canada
11Departments of Psychiatry, Neurology and Human Genetics, McGill University, Douglas Hospital Research Centre, Montreal, QC, Canada
12Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
13Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
14Department of Psychiatry, Ludwig Maximilians University, Munich, Germany
15Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland
16Weskoppies Hospital, Department of Psychiatry, University of Pretoria, Pretoria, Republic of South Africa
17Laboratory of Human Neurogenetics, Rockefeller University, New York, NY, USA
18Neuroscience Center, University of Helsinki, Helsinki, Finland
19Department of Psychiatry, New York University, New York, NY, USA
20The Nathan S Kline Institute for Psychiatric Research, Orangeburg, New York, NY, USA
Correspondence: Dr C Francks, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK. E-mail: clyde.francks@well.ox.ac.uk
21These authors contributed equally to this work.
Received 9 August 2006; Revised 6 June 2007; Accepted 19 June 2007; Published online 31 July 2007.
Left–right asymmetrical brain function underlies much of human cognition, behavior and emotion. Abnormalities of cerebral asymmetry are associated with schizophrenia and other neuropsychiatric disorders. The molecular, developmental and evolutionary origins of human brain asymmetry are unknown. We found significant association of a haplotype upstream of the gene LRRTM1 (Leucine-rich repeat transmembrane neuronal 1) with a quantitative measure of human handedness in a set of dyslexic siblings, when the haplotype was inherited paternally (P=0.00002). While we were unable to find this effect in an epidemiological set of twin-based sibships, we did find that the same haplotype is overtransmitted paternally to individuals with schizophrenia/schizoaffective disorder in a study of 1002 affected families (P=0.0014). We then found direct confirmatory evidence that LRRTM1 is an imprinted gene in humans that shows a variable pattern of maternal downregulation. We also showed that LRRTM1 is expressed during the development of specific forebrain structures, and thus could influence neuronal differentiation and connectivity. This is the first potential genetic influence on human handedness to be identified, and the first putative genetic effect on variability in human brain asymmetry. LRRTM1 is a candidate gene for involvement in several common neurodevelopmental disorders, and may have played a role in human cognitive and behavioral evolution.
Keywords:
handedness, schizophrenia, association, imprinted gene, brain asymmetry
