Troisi A. Genetics of adult attachment and the endogenous opioid system. World J Psychiatry 2022; 12(8): 1105-1107 [PMID: 36158306 DOI: 10.5498/wjp.v12.i8.1105]
Corresponding Author of This Article
Alfonso Troisi, MD, Associate Professor, Department of Systems Medicine, University of Rome Tor Vergata, via Montpellier 1, Rome 00133, Italy. alfonso.troisi@uniroma2.it
Research Domain of This Article
Psychiatry
Article-Type of This Article
Letter to the Editor
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Psychiatry. Aug 19, 2022; 12(8): 1105-1107 Published online Aug 19, 2022. doi: 10.5498/wjp.v12.i8.1105
Genetics of adult attachment and the endogenous opioid system
Alfonso Troisi
Alfonso Troisi, Department of Systems Medicine, University of Rome Tor Vergata, Rome 00133, Italy
Author contributions: Troisi A wrote the letter.
Conflict-of-interest statement: The author reports no relevant conflicts of interest for this article.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Alfonso Troisi, MD, Associate Professor, Department of Systems Medicine, University of Rome Tor Vergata, via Montpellier 1, Rome 00133, Italy. alfonso.troisi@uniroma2.it
Received: January 14, 2022 Peer-review started: January 14, 2022 First decision: April 18, 2022 Revised: April 24, 2022 Accepted: July 20, 2022 Article in press: July 20, 2022 Published online: August 19, 2022
Core Tip
Core Tip: Genetic studies of attachment should target the endogenous opioid system. Candidate gene studies of adult individuals have shown that variation in the mu-opioid receptor gene (OPRM1) influences attachment behavior. Early maternal care and the A/A genotype interact in modulating levels of fearful attachment. Compared to their counterparts carrying the A/A genotype, individuals expressing the minor 118G allele show lower levels of avoidant attachment. Brain imaging research has strengthened the biological plausibility of candidate gene studies. The avoidance dimension of attachment correlates negatively with mu-opioid receptor availability in the thalamus and anterior cingulate cortex, as well as the frontal cortex, amygdala, and insula.
