Children with high Callous-Unemotional (CU) traits show deficits in recognizing and processing facial expressions. Alterations in emotion recognition have been linked to a higher synaptic concentration of monoaminergic neurotransmitters. The current study investigated the relationship between the MAOA-Low-activity alleles and the ability to recognize and process facial expressions in 97 male children (8–12 years old) diagnosed with disruptive behavior disorder. Participants completed a computerized emotion-recognition task while an eye-tracking system recorded the number (Fixation Count, FC) and length (Fixation Duration, FD) of fixations to the eye region of the emotional stimuli. Children with high CU traits exhibited lower scores in recognition of sadness and anger, and lower FC and FD for sadness and fear than children with low CU traits. Children carrying the MAOA-Low-activity alleles displayed lower FD for sadness, and FD and FC for fear than those carrying the MAOA-High-activity alleles. These genetic effects appeared even stronger in children with CU traits. Moderation analysis revealed that CU traits were associated with lower FC and FD for fear, and lower FD for sadness, probably due to the MAOA-Low-activity alleles. Our findings, although to be replicated, suggest MAOA-Low-activity alleles as potential genetic biomarkers to identify CU children in need of training focused on emotion processing.

具有高度冷酷无情（CU）特征的儿童在识别和处理面部表情方面表现出缺陷。情绪识别的改变与单胺能神经递质突触浓度的升高有关。目前的研究调查了97 名被诊断患有破坏性行为障碍的男孩（8-12 岁）的MAOA低活性等位基因与识别和处理面部表情的能力之间的关系。参与者完成计算机化的情绪识别任务，同时眼球追踪系统记录对情绪刺激的眼睛区域的注视次数（注视计数，FC）和长度（注视持续时间，FD）。与低 CU 特质的儿童相比，高 CU 特质的儿童在识别悲伤和愤怒方面表现出较低的分数，并且在悲伤和恐惧方面表现出较低的 FC 和 FD。与携带MAOA高活性等位基因的儿童相比，携带MAOA低活性等位基因的儿童表现出较低的悲伤 FD 以及恐惧 FD 和 FC 。这些遗传效应在具有 CU 特征的儿童中显得更为强烈。调节分析显示，CU 特征与恐惧时较低的 FC 和 FD 以及悲伤时较低的 FD 相关，这可能是由于MAOA低活性等位基因所致。我们的研究结果虽然有待重复，但表明MAOA -低活性等位基因作为潜在的遗传生物标志物，可以识别需要进行情绪处理培训的 CU 儿童。