Tryptophan hydroxylase-1 (TPH1) is the rate-limiting enzyme in serotonin biosynthesis, and allelic variations at the TPH1 locus have been implicated in the pathophysiology of depression. Using 1.5-Tesla functional magnetic resonance imaging, we investigated the possible relationship between TPH1 A218C polymorphism and amygdala response to negative facial stimuli in twenty-six right-handed female subjects with major depressive disorder (MDD). Genotyping was performed with the polymerase chain reaction. We found a significant association between A allele of the TPH1 A218C polymorphism and neural activations in response to negative facial stimuli. Subjects with the A allele of the TPH1 A218C polymorphism showed greater brain activity in the bilateral amygdala under the sad versus the neutral condition compared to subjects homozygous for the C allele. Our results suggest that the A218C polymorphism of the TPH1 gene serves as a modulator of amygdala activity in patients with MDD.

中文翻译：

---

色氨酸羟化酶 1 基因 A218C 多态性对重度抑郁症患者情感面部刺激反应的杏仁核活性的影响

色氨酸羟化酶-1 (TPH1) 是血清素生物合成中的限速酶，TPH1 基因座的等位基因变异与抑郁症的病理生理学有关。使用 1.5 特斯拉功能磁共振成像，我们研究了 26 名患有重度抑郁症 (MDD) 的右利​​手女性受试者的 TPH1 A218C 多态性与杏仁核对负面面部刺激的反应之间的可能关系。用聚合酶链式反应进行基因分型。我们发现 TPH1 A218C 多态性的 A 等位基因与响应负面面部刺激的神经激活之间存在显着关联。与 C 等位基因纯合的受试者相比，具有 TPH1 A218C 多态性的 A 等位基因的受试者在悲伤与中性条件下的双侧杏仁核中表现出更大的大脑活动。