Results: Compared with healthy controls, the relative telomere length (median: 0.88 vs. 0.99, p = 0.009), SIRT1 (median: 0.89 vs. 0.99, p = 0.002), and Ku80 (median: 0.87 vs. 0.96, p < 0.001) expression levels were consistently lower in the peripheral blood mononuclear cells among patients with bronchiectasis and modestly discriminated patients with bronchiectasis from healthy controls. Here, XRCC5 is linked to bronchiectasis.