Notably, ebi-a-GCST90001566 (naïve CD4-CD8- T cell absolute count) exhibits a significant causal relationship with ESCC, boasting a maximum odds ratio (OR) of 1.14, a 95% confidence interval (CI) ranging from 1.03 to 1.27, and a P-value <0.05 (Fig. 1). This evidence concerns the gene CD8A and esophageal squamous cell carcinoma.