A moderate relationship was identified between CHRNA5 rs16969968 and COPD risk under the allelic and dominant models in all populations; between CHRNA3 rs12914385 and LC risk under all three models in Caucasians; between CHRNA3 rs8042374 and LC risk under the allelic and dominant models in Caucasians; between CHRNA3 rs938682 and LC risk under the allelic model in all populations; between CHRNA5 rs16969968 and LC risk under the allelic and dominant models in Caucasians; and between CHRNA5 rs588765 and LC risk under the allelic and dominant models in Caucasians. The gene discussed is CHRNA5; the disease is chronic obstructive pulmonary disease.