Deregulation of the renin–angiotensin system (RAS) plays an important role in suicide. Angiotensin converting enzyme (ACE) gene is a key component in this system. The relationship between insertion/deletion (I/D) polymorphism of ACE gene with suicide attempt (SA) is controversial. According to previous studies, allele D in this polymorphism has been considered as a potential risk factor for suicide. However, no study has been conducted in Iran to investigate this matter. This case–control study has focused on investigating the association of ACE I/D polymorphism (rs1799752) with SA in an Iranian population. The frequency of genotypes was 14% for II, 55% for ID, and 31% for DD in the case group (100 persons), and 18% for II, 74% for ID, and 8% for DD in control group (100 persons). Results show there was a significant difference in the distribution of ACE I/D polymorphism genotypes in men with SA compared to controls, as well as in women with SA compared to controls. Also, there was a significant association between DD genotype and the risk of SA compared to II genotype as reference. The severity of depression was significantly different between DD and II genotypes in SA group. According to the results, we suggest that the presence of DD genotype is possibly associated with an increased risk of SA. Maybe part of that is related to severity of depression in DD genotypes carriers of ACE I/D polymorphism.

肾素-血管紧张素系统（RAS）的失调在自杀中起重要作用。血管紧张素转换酶（ACE）基因是该系统的关键组成部分。ACE基因的插入/缺失（I / D）多态性与自杀未遂（SA）之间的关系是有争议的。根据以前的研究，这种多态性的等位基因D被认为是自杀的潜在危险因素。但是，伊朗尚未进行任何调查此事的研究。该病例对照研究的重点是调查伊朗人群中ACE I / D多态性（rs1799752）与SA的关联。在病例组（100人）中，II型的基因型频率为14％，ID的为55％，DD的为31％（对照组，II型的为18％，ID的为74％，DD的为8％（100））人）。结果显示，与对照组相比，SA男性患者中ACE I / D多态性基因型的分布存在显着差异，与对照组相比，SA女性患者中ACE I / D多态性基因型的分布存在显着差异。同样，与II基因型相比，DD基因型与SA风险之间存在显着关联。SA组DD和II基因型的抑郁严重程度差异显着。根据结果​​，我们认为DD基因型的存在可能与SA风险增加有关。可能部分原因与ACE I / D多态性的DD基因型携带者的抑郁严重程度有关。与II基因型相比，DD基因型与SA风险之间存在显着相关性。SA组DD和II基因型的抑郁严重程度差异显着。根据结果​​，我们认为DD基因型的存在可能与SA风险增加有关。可能部分原因与ACE I / D多态性的DD基因型携带者的抑郁严重程度有关。与II基因型相比，DD基因型与SA风险之间存在显着相关性。SA组DD和II基因型的抑郁严重程度差异显着。根据结果​​，我们认为DD基因型的存在可能与SA风险增加有关。可能部分原因与ACE I / D多态性的DD基因型携带者的抑郁严重程度有关。