Genetics of Linguistic and Non-Linguistic Development

在表面上正常的儿童中，有5%到10%在学习书面语言或口语方面存在困难。双胞胎研究是最常见的研究类型，用于梳理环境和遗传因素对语言发展的影响。因为同卵双胞胎的等位基因100%相同，而异卵双胞胎的等位基因只有50%相同，如果同卵双胞胎的语言能力比异卵双胞胎更相似，这表明遗传因素在语言中起作用。此外，双胞胎的语言障碍和语言迟缓率是单胎的两倍，这可能反映了与双胞胎有关的产前和产后环境危害。因此，双胞胎研究可以用来研究特定的环境因素如何影响语言发展。该项目将使用来自450对双胞胎的纵向数据来研究遗传和产前和产后环境因素如何影响语言和非语言发展。该项目将解决以下关键问题：1。遗传因素在语言正常儿童和语言障碍儿童的语言和非语言发展中起多大作用？这些遗传因素对语言（或语言的子成分）有多特殊？产前和产后早期环境因素在多大程度上影响语言和非语言发展？这些遗传和环境因素对发育的影响有多稳定？环境和遗传因素之间的相互作用如何影响正常和语言障碍儿童的语言和非语言发展？语言相关学习障碍的直接和间接成本对受损儿童、他们的家庭和社会都是巨大的。这项研究可能有助于揭示哪些环境因素可以保护儿童免受损害，哪些环境因素会增加他们的风险。这项研究还可能为遗传因素和环境因素如何相互作用以提高或降低语言和非语言障碍的风险提供必要的见解。有了这些知识，临床医生和教师可能能够定制治疗和教育实践，以最大限度地发挥每个孩子的潜力。

Between 5 to 10% of apparently normal children have difficulty acquiring written or spoken language. Twin studies are the most common type of study used to tease apart the impact of environmental and genetic factors on language development. Because identical twins share 100% of their alleles and fraternal twins share only 50% of their alleles, if identical twin pairs' linguistic abilities are more similar than fraternal twin pairs', this suggests that genetic factors play a role in language. Furthermore, the rate of language impairments and delays is twice as high for twins as singletons, probably reflecting pre- and postnatal environmental hazards associated with twinning. Thus, twin studies can be used to investigate how specific environmental factors affect language development. This project will use longitudinal data from 450 twin pairs to investigate how genetic and prenatal and postnatal environmental factors affect linguistic and nonlinguistic development. The project will address the following key questions:1. How great a role do genetic factors play in the linguistic and nonlinguistic development of linguistically normal and language-impaired children?2. How specific to language (or subcomponents of language) are these genetic factors?3. To what extent do prenatal and early postnatal environmental factors affect linguistic and nonlinguistic development?4. How developmentally stable are the effects of these genetic and environmental factors?5. How do interactions among environmental and genetic factors affect normal and language-impaired children's linguistic and non-linguistic development?The direct and indirect costs of language-related learning disabilities are enormous to the impaired child, their family and society. This study may help uncover which environmental factors protect children from impairments and which increase their risk. This study may also provide needed insight into the ways in which genetic factors and environmental factors interact to raise or lower the risk of linguistic and nonlinguistic impairment. Armed with this knowledge, clinicians and teachers may be able to tailor therapeutic and educational practices so as to maximize each child's potential.