rs12354968 (VTI1A): Tobacco and Alcohol Use Variant

Key takeaways

• rs12354968 is a genetic variant near VTI1A (Vesicle Transport through Interaction with t-SNAREs 1A), a gene involved in moving molecular cargo inside cells via membrane-bound transport vesicles.
• A genome-wide study of approximately 3.4 million people from diverse ancestries examined loci associated with tobacco and alcohol use, and this region was among those reported.
• In subcutaneous fat tissue, the alternate allele at this locus is linked to reduced VTI1A expression, based on data from 953 tissue donors.
• Most variants in the underlying study showed consistent effect sizes across different ancestry groups, though polygenic risk scores built in one ancestry performed poorly when applied to others.
• Specific effect size data for this individual variant were not detailed in the provided study text, so the evidence for this locus should be considered preliminary.

What the research says A multi-ancestry genome-wide association study (GWAS) covering approximately 3.4 million individuals from four major ancestry groups identified 2,143 genomic loci (containing 3,823 independently associated variants) linked to tobacco and alcohol use behaviors including smoking initiation, cigarettes per day, smoking cessation, age at first regular smoking, and drinks per week. The study found that greater sample size and genetic diversity improved locus discovery and fine-mapping resolution, with the large majority of identified variants showing consistent effect sizes across ancestry groups. The alternate allele at rs12354968 is associated with reduced VTI1A expression in subcutaneous adipose (under-skin fat) tissue based on GTEx data from 953 tissue donors (slope approximately -0.10, p=4.8e-5) GTEx Portal.

Reported associations

• Tobacco and alcohol use phenotypes: rs12354968 lies within a genomic region examined in a large multi-ancestry GWAS covering smoking initiation (n=3,383,199), cigarettes per day (n=784,353), smoking cessation (n=1,400,535), age at smoking onset (n=728,826), and drinks per week (n=2,965,643); specific association statistics for this individual variant are not detailed in the provided study text.
• VTI1A expression in subcutaneous adipose tissue: the alternate allele is linked to reduced VTI1A expression in subcutaneous fat tissue (effect slope approximately -0.10, p=4.8e-5, n=953 tissue donors) GTEx Portal.

Evidence quality The multi-ancestry GWAS is among the largest of its kind for tobacco and alcohol use, drawing on approximately 3.4 million participants (roughly 21% non-European) across 60 cohorts, which affords substantial statistical power at the locus level. However, the provided study text does not report association statistics specific to rs12354968, so the strength of its individual signal cannot be directly assessed here. The GTEx eQTL finding in subcutaneous adipose tissue (p=4.8e-5, FDR less than 0.05 threshold applied, n=953 donors) meets standard significance criteria for tissue-specific expression effects, but represents a mechanistic observation rather than a behavioral or disease outcome. No replication data or conflicting findings for this variant were present in the provided sources, and the evidence for this locus should be treated as preliminary until specific association results are reported.

Tissue-specific expression effects

• VTI1A: the alternate allele is associated with reduced expression in subcutaneous adipose (under-skin fat) tissue; no other tissues reached significance in the provided GTEx data GTEx Portal.

Lifestyle considerations

• Tobacco use (lifestyle, mixed, low): a large multi-ancestry genome-wide study found this genomic region among loci associated with tobacco use behaviors, though the direction and magnitude of effect for this specific variant are not specified in the provided text.
• Alcohol consumption (lifestyle, mixed, low): the same large genome-wide study examined drinks per week in nearly 3 million individuals and identified loci in this region, though specific findings for this variant are not detailed in the provided text.