NOS3 and lung disorder: In general, NOS3 gene polymorphisms have been reported to act as ‘susceptibility genes’ in various cardiovascular and pulmonary diseases.7 GT substitution in exon 7 of codon 298,8 4a/b polymorphism in intron 4,9, 10 T-786C mutation in the 5'-flanking region,11, 12 and high numbers of CA repeat in intron 13 of the NOS3 gene are also associated with an excess risk for CAD.13 Among them, a common variant located in exon 7 (G984T) of the NOS3 gene that modifies its coding sequence (Glu298Asp) has been linked by several groups to the risk for CAD and acute myocardial infarction (MI).