Developmental-genetic effects on level and change in childhood fears of twins during adolescence
Developmental-genetic effects on level and change in childhood fears of twins during adolescence
复制标题
DOI：
10.1111/j.1469-7610.2008.01956.x
复制
发表时间：
2008-11-01
影响因子：
7.6
通讯作者：
Silberg, Judy L.
中科院分区：
文献类型：
--
作者：
Eaves, Lindon J.;Silberg, Judy L.
背景资料：如果特定恐惧的适应意义随年龄而变化，那么在最显著的年龄，基因对个体差异的贡献可能最低。基因和环境的作用，在五个常见的童年恐惧的发展遗传轨迹中探索1094同性对男性和女性的单卵双胞胎和双卵双胞胎在青春期（8-18岁）的三个场合进行评估。研究方法：在每次评估时，提取受试者的Ollendick恐惧时间表（FSSC-R）中五个相关恐惧的二分自评。通过拟合项目反应理论（“IRT”）模型，研究了基因和环境对整体恐惧水平和青少年下降率的影响，该模型允许个体在初始恐惧水平（“截距”）和青少年变化率（“斜率”）方面的遗传和环境差异。不同形式的模型进行了探索，使用马尔可夫链蒙特卡罗（MCMC）方法，从原始响应中推导出受试者和项目参数的后验分布。结果：加性遗传差异影响五个恐惧项目的公因子。同样的基因也会影响随着年龄的变化，特别是在男孩身上。男性青少年具有较高的整体遗传易感性，儿童期的恐惧往往表现出较慢的恢复与年龄相比，相对较低的初始值。因此，遗传变异显然随着年龄的增长而增加。结论：这一发现与一个预测是一致的，即在特定刺激最显著的年龄，遗传差异的调节将是最强的，因此加性遗传方差将是最小的。项目不同的程度上，他们是敏感的潜在的随机差异的发展变化的速度。随着年龄的变化率的个体差异，男孩比女孩更显着。
Background: If the adaptive significance of specific fears changes with age, the genetic contribution to individual differences may be lowest at the age of greatest salience. The roles of genes and environment in the developmental-genetic trajectory of five common childhood fears are explored in 1094 like-sex pairs of male and female monozygotic and dizygotic twins assessed on up to three occasions during adolescence (ages 8-18 years). Methods: Dichotomous self-ratings of a cluster of five correlated fears from Ollendick's schedule of fears (FSSC-R) were extracted for subjects at each occasion of assessment. The effects of genes and environment on overall level of fears and rates of adolescent decline were explored by fitting an item-response theory ('IRT') model that allowed for individual genetic and environmental differences in initial fear level ('intercept') and rates of adolescent change ('slope') across the repeated waves of measurement. Different forms of the model were explored using Markov Chain Monte Carlo (MCMC) methods to derive the posterior distribution of subject and item parameters from the raw responses. Results: Additive genetic differences affect the common factor underlying the five fear-items. The same genes also affect rates of change with age, especially in boys. Male adolescents with higher overall genetic predisposition to childhood fears tended to show slower recovery with age than subjects with relatively low initial values. Thus, the genetic variance apparently increases with age. Conclusions: This finding is consistent with a prediction that the regulation of genetic differences will be strongest, and thus the additive genetic variance will be smallest, at the age when the particular stimulus is most salient. Items differed in the extent to which they were sensitive to underlying random differences in the rate of developmental change. Individual differences in rates of change with age were more marked in boys than girls.