"In marriage, people are also influenced by their own and their partner's genetic predispositions."
The researchers also found that people with the GG genotype reported less anxious attachment in their marriage, which also benefited their relationship.
Anxious attachment is a style of relationship insecurity that develops from past experiences with close family members and partners over the life course, and is associated with diminished self-worth, high rejection sensitivity, and approval-seeking behavior.
The study found that an individual's GG genotype and their partner's GG genotype together account for about 4 per cent of the variance of marital satisfaction.
The authors said that although this percentage appears small, it is a significant influence considering other genetic and environmental factors to which couples are exposed.
Each participant completed a survey about their feelings of marital security and satisfaction and also provided a saliva sample for genotyping. The study is published in the journal PLOS ONE.
This article originally appeared on the Daily Telegraph.