White Victoria M, Hopper John L, Wearing Alexander J, Hill David J
Centre for Behavioural Research in Cancer, The Cancer Council Victoria, Victoria, Australia.
Addiction. 2003 Aug;98(8):1087-100. doi: 10.1046/j.1360-0443.2003.00427.x.
To incorporate a psychosocial model of tobacco smoking into a behaviour genetic design to examine genetic and environmental influences on variation in smoking involvement.
Longitudinal twin study.
Twins initially aged between 13 and 18 years and registered with the Australian Twin Registry were surveyed three times between 1988 and 1996. A total of 414 pairs of identical and same-sex fraternal twin pairs participated in all three surveys, aged between 20 and 25 at wave 3. Biometric modelling estimated the influence of genetic and environmental factors in determining variation in smoking at each wave, both before and after adjusting for perceived smoking behaviours of peers and parents.
Twins answered a questionnaire on their own smoking status and reported on the use of tobacco by parents and friends as they perceived it, at each survey wave.
At all three surveys, current smokers were more likely to have parents who smoked and to have smokers among their peers. Genes and environmental factors, both common and unique, contributed to variation in smoking behaviours. However, after controlling for the smoking behaviours of peers and parents, the role of genes in determining variation in smoking involvement was reduced by 100% at wave 1 and by 30% at wave 2. Friends' smoking reduced the magnitude of the common environment variance by 11%, 30% and 40% at waves 1, 2 and 3, respectively. Parents' smoking behaviours explained part of the common environment. Biometric modelling of the covariation between smoking involvement and peer smoking suggested that genes might influence smoking involvement at wave 1 by influencing choice of peers.
Environmental factors play the greatest role in determining variation in tobacco smoking among adolescents and young adults. Among adolescents, genes may influence variation in smoking behaviours indirectly by influencing choice of peers. However, genes seem to have a direct influence on variations in the smoking behaviours of young adults.
将吸烟的社会心理模型纳入行为遗传学设计，以研究基因和环境对吸烟参与度差异的影响。
纵向双胞胎研究。
最初年龄在13至18岁之间并在澳大利亚双胞胎登记处登记的双胞胎，于1988年至1996年间接受了三次调查。共有414对同卵双胞胎和同性异卵双胞胎参与了所有三次调查，第三次调查时年龄在20至25岁之间。生物统计学模型估计了基因和环境因素在每次调查时（在校正同龄人及父母的感知吸烟行为之前和之后）对吸烟差异的影响。
在每次调查时，双胞胎回答关于自己吸烟状况的问卷，并报告他们所感知的父母和朋友的吸烟情况。
在所有三次调查中，当前吸烟者的父母更有可能吸烟，其同龄人中也更有可能有吸烟者。基因以及共同和独特的环境因素都导致了吸烟行为的差异。然而，在校正同龄人及父母的吸烟行为后，基因在决定吸烟参与度差异方面的作用在第一次调查时降低了100%，在第二次调查时降低了30%。朋友的吸烟行为分别使共同环境方差在第一次、第二次和第三次调查时降低了11%、30%和40%。父母的吸烟行为解释了部分共同环境因素。对吸烟参与度与同龄人吸烟之间的协变量进行的生物统计学模型表明，基因可能在第一次调查时通过影响同龄人选择来影响吸烟参与度。
环境因素在决定青少年和年轻人吸烟差异方面起最大作用。在青少年中，基因可能通过影响同龄人选择间接影响吸烟行为差异。然而，基因似乎对年轻人的吸烟行为差异有直接影响。
