The aims of the studies described in this manuscript were to (i) define the genetic architecture surrounding the SNPs at the GSTCD/INTS12 locus at 4q24 previously found to be strongly associated with lung function, (ii) assess how GSTCD and INTS12 gene expression is regulated, (iii) analyse GSTCD and INTS12 protein expression in non-diseased lung tissue and lung tissue from individuals with COPD and (iv) assess whether GSTCD or INTS12 protein expression changes during fetal development. The gene discussed is GSTCD; the disease is chronic obstructive pulmonary disease.