Figure 2: Risk of ACS and NOS1 AAT repeats in intron 13. The risk of ACS (1-[controls/(cases+controls)]) is plotted against the number of NOS1 AAT repeats in patients with SCD with physician-diagnosed asthma (closed circles) and without physician- diagnosed asthma (SCDNA). ACS: acute chest syndrome, NOS1: nitric oxide synthase 1 gene, SCDNA: sickle cell disease physician diagnosed asthma, reproduced with permission from [18].