Anxiety ranks as the second most prevalent psychiatric ailment, trailing only depression (Vos et al., 2017; Martin, 2022). Globally, the average prevalence of anxiety is approximately 7.3 %. However, during the COVID-19 pandemic, this rate potentially surged to over thrice its usual figures (Santabárbara et al., 2021). Specifically, in the US, based on the 2004 National Comorbidity Study, nearly 34 % of the population will experience anxiety at some point in their lives (Kessler et al., 2012; Szuhany and Simon, 2022). Manifestations of anxiety span a spectrum, encompassing social anxiety, generalized anxiety, panic attacks, and agoraphobia, with social anxiety reigning as the predominant form (Kessler et al., 2012). The trajectory of anxiety is often protracted, significantly encumbering one's quality of life and overall functionality (Szuhany and Simon, 2022). Beyond its primary manifestations, anxiety often coexists with, or exacerbates, a range of medical conditions such as cardiovascular, gastrointestinal, pulmonary diseases, cancer, chronic pain, and migraines (Kariuki-Nyuthe and Stein, 2015; Szuhany and Simon, 2022). Regrettably, a staggering 41 % of anxiety-afflicted individuals remain untreated, resulting in an estimated 26,417 years lived in incapacitation globally (Kroenke et al., 2007; Vos et al., 2017). Given this backdrop, the quest for efficacious anxiety treatments is both urgent and indispensable.

At present, the vanguard treatments for anxiety encompass both pharmacological and psychotherapeutic interventions. The pharmacological treatments predominantly recommended for anxiety disorders are selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors, chosen based on their empirical efficacy and safety profiles (Gosmann et al., 2021; Chawla et al., 2022). When it comes to psychotherapy, cognitive behavioral therapy stands out as the primary recommendation for managing anxiety disorders (Carpenter et al., 2018). However, certain scholars advocate for the benefits of psychodynamic therapy as a notable option (Keefe et al., 2014). While these therapeutic modalities have demonstrated efficacy in ameliorating anxiety to a degree, it's noteworthy that despite over five decades of rigorous research, innumerable randomized controlled trials, and substantial financial investments, the potency of both psychotherapies and pharmacotherapies for mental disorders remains modest (Leichsenring et al., 2022). This suggests a potential saturation point in treatment efficacy given the current research paradigms. Hence, a profound comprehension of the fundamental mechanisms driving anxiety, coupled with the identification of innovative therapeutic targets, is imperative to catalyze further advancements in this domain.

In the realm of drug discovery and development, we are confronted with a stark reality: approximately nine in ten drugs falter when transitioning to clinical application (Harrison, 2016). A major reason for this high failure rate is the insufficient utilization of human genetics in appraising targets for drug discovery endeavors (Razuvayevskaya et al., 2023). However, with the rapid advancement of human genomics, expansive biobank-driven genetic studies have emerged as powerful tools, poised to redress these deficiencies by facilitating the identification and validation of novel drug targets (Trajanoska et al., 2023). Given that the majority of drug targets are proteins, the proteome-wide association study (PWAS) offers a promising avenue. By integrating human proteomic datasets with findings from genome-wide association study (GWAS), the PWAS approach aims to spotlight potentially pathogenic proteins, thereby streamlining the prioritization of prospective drug targets (Schmidt et al., 2020; Zheng et al., 2020).

To unearth potential causal genes influencing anxiety via their cis-regulated brain protein abundance, we integrated the latest anxiety GWAS data with two distinct human brain proteomic datasets (ROS/MAP (Bennett et al., 2018) and Banner (Beach et al., 2015)) through a PWAS methodology, all underpinned by a discovery and confirmatory study framework (Fig. 1). Additionally, to probe the identified genes at both transcriptomic and proteomic dimensions, we embarked on a transcriptome-wide association study (TWAS) for anxiety, leveraging reference human brain transcriptomes from the Common Mind Consortium (CMC). Following this, the genes of significance underwent rigorous evaluation via an array of methodologies such as mendelian randomization (MR), colocalization, and conditional/joint analyses. Completing our comprehensive exploration, we conducted GO-KEGG pathway enrichment assessments, cell-type specific and brain region expression studies, and drug-gene and protein-protein interaction (PPI) network analyses. These analyses collectively illuminated the roles and potential mechanistic pathways of the pinpointed genes in the context of anxiety. Our study represents an innovative effort, offering a comprehensive perspective to identify anxiety-associated risk proteins, which hold immense promise as foundational targets for devising therapeutic interventions and diagnostic biomarkers for anxiety.