Molecular Genetics of Dyslexia: A component processes approach

随着人类基因组计划的到来，澳大利亚研究严重儿童阅读障碍的研究人员现在在理解基因与阅读障碍之间的复杂联系方面取得了突破。人们普遍认为，先前对阅读障碍的遗传学研究受到了限制，因为它们未能区分阅读过程中的不同组成过程和它们产生的阅读障碍的不同模式，也无法广泛地观察整个人类基因组。这项新研究解决了这两个问题。首先，研究人员开发了一个阅读的计算模型，该模型识别了在熟练阅读过程中所涉及的十几个基本心理过程。该模型为基因研究提供了极其精确的表型。其次，研究人员将利用2号、6号和15号染色体上已知感兴趣区域的高密度扫描，以及对基因组中已知位置的400个标记（DNA的小元素）进行全基因组扫描，从而使研究人员能够缩小新基因的位置以供阅读。因此，这项研究不仅有望完善我们对先前三种阅读障碍遗传标记基础的理解，而且还可能发现与基因组中特定阅读元素相关的新基因。该项目汇集了麦考瑞认知科学中心、澳大利亚基因组研究机构和加文研究所的资源，研究人员希望这项工作最终将导致识别失读症的基因，并改善澳大利亚阅读障碍的诊断和治疗。

With the advent of the human genome project, Australian researchers into serious childhood reading disorders are now in a position to make breakthroughs in understanding the complex linkages between genes and dyslexia. It is widely acknowledged that previous studies on the genetics of dyslexia have been limited by their failure to distinguish the different component processes in reading and the different patterns of dyslexia that they produce, and by being unable to look widely across the human genome. This new research addresses these two problems. Firstly, the researchers have developed a computational model of reading that identifies around a dozen basic mental processes which are recruited during skilled reading. This model provides the extremely precise phenotypes required for genetic research. Secondly, the researchers will take advantage of both very high density scans within known regions of interest on chromosomes 2,6, and 15, as well as a genome-wide scan of 400 markers small elements of DNA whose position within the genome is known, thus allowing researchers to narrow-down the location of new genes for reading. The research thus promises not only to refine our understanding of the basis for three previous genetic markers of dyslexia, but also to potentially uncover new genes related to specific elements of reading across the genome. The project pools the resources of the Macquarie Centre for Cognitive Science, the Australian Genome Research Facility, and The Garvan Institute and the researchers hope that the work will lead eventually to identifying the genes for dyslexia and to improved diagnosis and treatment of reading disorders in Australia.