HSPA1L and chronic obstructive pulmonary disease: Based on the above, we designed a genetic association study between SNPs in HSPA1A, HSPA1B, and HSPA1L and the susceptibility to COPD secondary to tobacco smoke and BBS, specifically, the effect on COPD susceptibility and severity in Mexican mestizo patients, as well as the effect on these genes’ mRNA and protein levels in lung cells.