Human behavior is influenced by both genetic and environmental factors. Monoamine oxidase A (MAOA) is among the most investigated genetic determinants of violent behaviors, while the monoamine oxidase B (MAOB) is explored in Parkinson's disease. We collected twenty-four post-mortem brain tissue datasets of 3871 and 1820 non-demented males and females, respectively, who died from causes not attributable to neurodegenerative diseases. The gene expressions of MAOA and MAOB (MAO genes) were analyzed in these subjects, who were further stratified according to age into eleven groups ranging from late Infancy (5−9 months) to centenarians (>100 years). MAO genes were differently expressed in brains during the entire life span. In particular, maximal and minimal expression levels were found in early life and around the teen years. Females tended to have higher MAO gene levels throughout their lives than those found in age-matched males, even when expressions were separately measured in different brain regions. We demonstrated the existence of age- and sex- related variations in the MAO transcript levels in defined brain regions. More in-depth protein studies are needed to confirm our preliminary results obtained only on messenger RNAs in order to establish the role played by MAO genes in human development.

人类行为受遗传和环境因素的影响。单胺氧化酶 A (MAOA) 是研究最多的暴力行为的遗传决定因素之一，而单胺氧化酶 B (MAOB) 在帕金森病中得到了探索。我们分别收集了 3871 名和 1820 名非痴呆男性和女性的 24 个死后脑组织数据集，他们死于非神经退行性疾病的原因。在这些受试者中分析了MAOA和MAOB（MAO基因）的基因表达，这些受试者根据年龄进一步分为 11 组，从婴儿晚期（5-9 个月）到百岁老人（>100 岁）。毛在整个生命周期中，基因在大脑中的表达不同。特别是，在生命早期和青少年时期发现了最大和最小的表达水平。即使在不同大脑区域分别测量表达时，女性一生中的MAO基因水平也往往高于年龄匹配的男性。我们证明了在特定大脑区域中MAO转录水平存在与年龄和性别相关的变化。需要更深入的蛋白质研究来证实我们仅在信使 RNA 上获得的初步结果，以便确定MAO基因在人类发育中所起的作用。