How is "Anxious Temperament" encoded by the genome?
According to the World Health Organization, anxiety and depressive disorders are a leading source of disability, affecting hundreds of millions of people. Anxious temperament is one of the five domains of affective temperament, along with depressive, hyperthymic (abnormally positive), cyclothymic (emotional ups and downs), and irritable. A person who was extremely shy and nervous in his/her childhood is more prone to develop anxiety disorders and depression later in life. They're also more likely to self-medicate with alcohol and other drugs.
Previous research indicated that such temperaments like anxiety are hereditary– showing affective disorder in patients and relatives. Making the use case of a genome-wide association study (GWASs) relevant to identifying genes. However, previously, no whole- genome-wide analysis was performed for affective temperaments in a general population sample, and there has been only one GWAS in a bipolar patient sample.
Researchers performed a pilot GWAS on five affective temperaments in a European general population sample in this context. Phenotypic and genotypic data from 775 participants in the Budapest cohort, a part of the NewMood project, were used for the GWAS. Participants filled out the NewMood questionnaire pack, including the standardized Hungarian version of the 110-item Temperament Evaluation of Memphis, Pisa, Paris, and San Diego (TEMPS-A) questionnaire to measure five affective temperaments; irritable, depressive, hyperthymic, cyclothymic, and anxious temperament. As for anxious temperament, participants were asked to answer yes or no questions such as “I am often fearful of someone in my family coming down with a serious disease” and “I’m always thinking someone might break bad news to me about a family member”. Results show that there is a relationship between rs1281465 in LOC105377110 gene, rs3799007 in ADGRB3 gene, rs13251367, rs56381, rs1553677 with anxious temperament with suggestive significance. The ADGRB3 gene is expressed almost exclusively in the brain and encodes the Adhesion G protein-coupled receptor B3, a protein with a pivotal role in the central nervous system development, maintenance, and plasticity, including regulating synaptic development during development and adulthood. In the past, this gene has been associated with impulsivity/negative urgency/behavioral disinhibition and educational attainment.
A major limitation of this study could be the small sample size highlighted, but at the same time, this is balanced by the careful sample characterization and precise attainment of the investigated trait and multiple analytical approaches focusing on functional analyses besides SNP and gene levels. Read more about the study here:
https://pubmed.ncbi.nlm.nih.gov/34075027/
Are you interested in learning more about your genetic tendency for anxious temperament? You can login to your Genomelink YOUR TRAITS to see this new genetic trait.
