The largest study of the trait behind this found it was not one trait. “Worry” and “depressed affect” came apart in the data, which is a finding about the questionnaire as much as about the person.
Why this topic Anxiety is the word a generation uses about itself, and the measurement it is usually described with turns out to be adding two things together.
Solid lines are connections this site curates. Dashed lines mean the two ends share a research paper — worth knowing, and not a claim that one explains the other.
Counted in Europe PMC, where the title or abstract names both this topic and that rsID. The number is papers, not evidence of a cause.
BDNF
Smoking behavior
18 papers →OPRM1
Opioid receptor sensitivity
4 papers →CACNA1C
Schizophrenia
3 papers →FTO
Obesity
3 papers →RIMS1
Schizophrenia
2 papers →MYH6
Electrocardiographic traits
2 papers →FADS1
Crohn's disease
1 paper →TYR
Skin pigmentation
1 paper →ANK3
Autism spectrum disorder, attention deficit-hyperactivity disorder, bipolar disorder, major depressive disorder, and schizophrenia (combined)
1 paper →BDNF
Body mass index
1 paper →IRF4
Freckling & sun sensitivity
1 paper →ADH1B
Alcohol metabolism speed
1 paper →SNCA
Parkinson's disease
1 paper →CYP2C19
CYP2C19 *2 — clopidogrel activation
1 paper →BDNP
Menarche (age at onset)
1 paper →Europe PMC, title and abstract only, searched for “anxiety disorder”, “neuroticism”, “worry”, “anxiety symptoms” alongside each published rsID. Full text was not counted: it returns every paper with an rsID buried in a supplementary table. Recounted monthly.