Chronic AF cohort studies further corroborated this upregulation trend, notably demonstrating higher Cx40 expression in dialysis patients with AF (1.23 ± 0.12) versus non-AF dialysis controls (0.74 ± 0.03) and healthy subjects (0.69 ± 0.03, p < 0.0001) [47]. The gene discussed is GJA5; the disease is atrial fibrillation.