Liver enzymes

The Netherlands Twin Register (NTR) consists of individuals who have agreed to participate in twin-family studies and was established and is managed by the Department of Biological Psychology, VU University Amsterdam (see: https://tweelingenregister.vu.nl/). The NTR was established in 1987 and has enrolled around 120.000 twins and a roughly equal number of their relatives. The majority of twin families have participated one or more times in survey studies on a host of epidemiological variables including social demography, personality, lifestyle, somatic and mental health, and subsamples took part in biomaterial collection (e.g. DNA) and dedicated projects for e.g. neuropsychological, biomarker, and behavioral traits. The recruitment into the NTR is fully inclusive without any restrictions on enrolment. The NTR is committed to actively seek the commitment of its participants to science and their continued involvement in NTR research by maintaining a website, electronic newsletters, and the MijnNTR portal that provides personalized feedback to participants. The NTR resources, e.g. the longitudinal phenotyping, the extended pedigree structures, and the multi-generation genotyping allow for future twin-family research that will contribute to gene discovery, causality modelling, and studies of genetic and cultural inheritance of behavioral traits and mental and physical health. In the CID data catalogue, only the NTR projects for children and adolescents (<18 years of age) have been included. This is refered to as the Young Netherlands Twin Register (YNTR).

荷兰双生子登记库（Netherlands Twin Register, NTR）由自愿参与双生子家庭研究的个体组成，由阿姆斯特丹自由大学（VU University Amsterdam）生物心理学系建立并管理（详见：https://tweelingenregister.vu.nl/）。该登记库始建于1987年，目前已收录约12万名双生子及其数量相近的亲属。绝大多数双生子家庭已参与过一项或多项针对多项流行病学变量的调查研究，涉及社会人口学、人格特征、生活方式、躯体与精神健康等领域；部分子样本参与了生物样本采集（如脱氧核糖核酸（DNA）样本）以及针对神经心理学、生物标志物与行为特征的专项研究。荷兰双生子登记库的招募全程秉持包容原则，对入组无任何限制。该登记库致力于通过维护官方网站、电子通讯以及为参与者提供个性化反馈的MijnNTR门户，积极寻求研究参与者对科学研究的支持，并推动参与者持续参与荷兰双生子登记库的相关研究。荷兰双生子登记库的各类资源——如纵向表型数据、扩展家系结构以及多世代基因分型技术——可为后续双生子家庭研究提供支撑，助力基因发现、因果关系建模以及行为特征与身心健康的遗传与文化继承相关研究。在CID数据目录中，仅收录了针对儿童与青少年（年龄<18岁）的荷兰双生子登记库研究项目，该子库被称为青年荷兰双生子登记库（Young Netherlands Twin Register, YNTR）。