According to the Daily Mirror: "5-HTA1 is thought to lower serotonin levels, a feel-good chemical, which causes people to feel uncomfortable in close relationships."
Carriers are also generally more neurotic and have a higher rate of depression.
And researchers found those attributes are "detrimental to the formation, quality and stability of relationships."
But some experts questioned the reliability of the research — this was from a relatively small sample size of 600 people, and all of them students.
One relationship expert told the Daily Mail: "If someone's difficulties with dating are flagged up to them, I believe they can learn to interact in a way that will make them more successful in meeting somebody."
Still, when Grandma asks you again this Thanksgiving why you're still not married, you can tell her she's at least a teeny bit responsible.
This video includes images from Know Your Meme and Tom Woodward / CC BY NC 2.0.