GC1F, GC1S, and GC2 are the three allelic variants (denoted as rs4588 and rs7041) of GC, and known to be associated with chronic obstructive pulmonary disease (COPD).
Subjects with a C allele at rs4588 exhibited a higher frequency of exacerbations (P = 0.0048), greater susceptibility to chronic obstructive pulmonary disease (P = 0.0003), and emphysema (P = 0.0029), and a tendency for rapid decline of airflow obstruction (P = 0.0927).
This correlation was found to be independent of COPD severity, smoking history, age, gender, body mass index, corticosteroid intake, seasonal variation and rs4588 (p<0.0001).