摘要：背景：已有一些研究指出母親吸菸或二手菸的暴露對於兒童神經行為發展會造成影響，然而基因多型性的修飾作用及經由基因甲基化機轉對此影響卻尚不清楚。此本研究的目的就是要探討二手菸暴露所造成的兒童神經行為發展的基因多型性修飾作用及基因甲基化機轉。目的：本研究主要有四的目的：第一，我們將負責執行六、七、八歲時的田野追蹤；第二，我們將探討子宮內或早期兒童時期的二手菸暴露情形；第三，我們將探討基因多型性對於二手菸暴露與兒童神經行為發展的修飾作用；第四，我們將探討二手菸的暴露與DNA甲基化程度的關係，以及對兒童神經行為發展所造成的影響。方法：本研究對象為2004年4月到2005年1月參與台北出生世代研究之孕婦及其嬰兒總計486對。我們在其產前即將其納入研究對象，並以結構性問卷進行問卷訪視及收集孕產婦血液及尿液，生產時亦收集新生兒臍帶血，血液並進一步分離成血漿與DNA以利後續之暴露量測與基因分析，出生後三天內以中文版神經行為評估量表由專業人員進行新生兒行為評估，於嬰兒2歲大時，使用嬰幼兒綜合發展測驗、兒童行為量表與語言發展量表，並請家長或主要照顧者填寫家庭環境觀察評估量表，並同時收集尿液及血液；利用高效能液相層析儀連結串聯的質譜儀(LC/MS/MS)進行臍帶血cotinine濃度分析；基因多型性方面已完成CYP1A1 Ile462Val、CYP1A1 MspI、GSTT1、 GSTM1、GSTP1等代謝基因。在2010-2013期間我們將持續追蹤小孩至8歲，測量2及6歲兒童血液及尿液的cotinine濃度，測量6至8歲的兒童神經認知及行為發展，使用Infinium methylation assay、ingenuity pathway analysis (IPA)、sodium bisulfite treated DNA sequence來選擇相關特殊基因，最後將使用high resolution melting analysis、multiplex methylation PCR來進行所有追蹤對象的相關特殊基因及其甲基化情形。預期結果：第一年將主要探討代謝基因多型性對於胎兒二手菸暴露與兒童神經行為發展的修飾作用；第二年主要進行臍帶血DNA全基因的甲基化分析，找出相關的特殊基因；最後一年主要探討胎兒及(或)兒童時期二手菸暴露與兒童神經行為發展的關係，同時也將考慮相關的特殊基因及其甲基化程度對前述關係的影響。
Abstract: Background: Maternal smoking or environmental tobacco smoke (ETS) has been reported in association with children’s neurobehavioral development but there is little known about genetic susceptibility to cigarette smoke on children’s neurobehavioral development. The epigenetic mechanism of maternal smoking or ETS exposure on children’s neurobehavioral development is also unknown. The aim of this study is to explore the modification effect of metabolic gene polymorphisms and epigenetic changes to maternal smoking or ETS on early children’s neurocognitive and behavioral development in the early childhood.Objectives: The objectives of this study are four folds: firstly, we are responsible for the field survey and biobank to follow up these children in each year up to the age of eight; secondly, we will describe the distribution of cotinine levels among reproductive-age women, neonates, and toddlers in the general population; third, we will analyze the gene-specific DNA methylation for cord blood DNA; and finally, we will explore the potential delayed effects of in-uetro and/or early ETS exposures on early childhood neurocognitive development and child behavior under the consideration of gene polymorphisms and DNA methylation.Methods: The study population was 486 mother-infant pairs who gave births in Taiwan between August 2004 and January 2005 from Taiwan Birth Panel Study. We interviewed them by a structured questionnaire before delivery, collected umbilical cord blood at birth and blood and urine at two years of age. The bloods were separated into plasma and DNA. We followed them by using the Neonatal Neurobehavioral Examination in Chinese Version after birth within three days and the Developmental Inventory for Infants and Toddlers, Child Behavior Checklist and MacArthur Communicative Development Inventory were also performed at two years of age. Cotinine in umbilical cord blood as an indicator of ETS was analyzed by using HPLC-MS/MS and the detection limited of this method was 0.05 ng/mL. Four metabolic genes, CYP1A1 MspI, CYP1A1 Ile462Val, GSTT1 and GSTM1 were also identified. During the 2010-2013 we will follow-up our subjects up to age 8, measure the cotinine level in children’s blood or urine at age 2 and 6, measure children’s neurocognitive development and behavioral problems at age 6-8, use Infinium methylation assay, ingenuity pathway analysis, sodium bisulfite treated DNA sequence to select specific genes, and use multiplex methylation PCR and high resolution melting analysis to identify those selected genes and their methylation profile in all study subjects.Anticipated results: For the first year, we will find genetic polymorphisms may modify the developmental neurotoxicity of in-utero ETS exposure on behavior problems and language development in the early childhood. For the second year, we will find the epigenetic changes in determine the susceptibility of ETS exposure. For the last year, we will find the association between in-utero and/or postnatal ETS exposure and children’s neurodevelopment under the consideration of epigenetic changes of selected genes.