Zhang Kejin, Zheng Zijian, Gao Xiaocai, Li Jing, Zhang Fuchang
Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an, China.
Neuropsychobiology. 2007;56(2-3):98-103. doi: 10.1159/000112950. Epub 2008 Jan 10.
Catechol-O-methyltransferase (COMT) gene was hypothesized to have a relationship with human prefrontal cortex (PFC) function and individual cognitive abilities. The object of this study was to investigate the possible impact of genotypes of COMT Val158Met polymorphism on cognitive ability among children living in the Qinba region in China.
A total of 305 children were included, 163 girls and 142 boys; both complete IQ evaluation and Val158Met genotyping results were obtained. The quantitative traits of psychometric IQ were calculated by using the Chinese Wechsler Intelligence Scale for Children. All subjects' genotypes of COMT gene Val158Met polymorphism were identified with the restriction fragment length polymorphism method.
The F test showed that the average scores (including the Full Scale IQ, Verbal Scale IQ, Performance Scale IQ and three index scores) did not significantly differ among different groups defined by Val158Met genotypes, neither in boys nor in the total group (p > 0.05). There was a significant difference between the average of Freedom from Distractibility score among different genotypes found in girls (p = 0.033).
Our results indicate that COMT gene Val158Met polymorphism may be related to the intelligence of Chinese girls, although the results cannot withstand multiple testing. Consequently, further studies with larger samples and perfect design still need place more emphasis on the gender difference and compensation effect of dopamine activity in PFC.
儿茶酚-O-甲基转移酶（COMT）基因被推测与人类前额叶皮质（PFC）功能及个体认知能力有关。本研究旨在探讨COMT基因Val158Met多态性的基因型对中国秦巴地区儿童认知能力的可能影响。
共纳入305名儿童，其中女孩163名，男孩142名；同时获得了完整的智商评估和Val158Met基因分型结果。采用中国韦氏儿童智力量表计算心理测量智商的定量指标。采用限制性片段长度多态性方法鉴定所有受试者COMT基因Val158Met多态性的基因型。
F检验显示，不同Val158Met基因型组的平均得分（包括全量表智商、言语量表智商、操作量表智商及三项指数得分）在男孩及总人群中均无显著差异（p>0.05）。女孩中不同基因型的注意力分散度得分平均值之间存在显著差异（p=0.033）。
我们的结果表明，COMT基因Val158Met多态性可能与中国女孩的智力有关，尽管该结果无法经受多重检验。因此，需要更大型样本和更完善设计的进一步研究，仍需更多关注PFC中多巴胺活性的性别差异和补偿效应。
