MT-CO2 and asthma: Beyond haplogroup comparisons, we identified 10 exonic mitochondrial variants associated with asthma risk through two complementary analyses: case-control association testing (Table 3) and exclusivity analysis (Table 4), within genes encoding subunits of Complex I (MT-ND1, MT-ND3, MT-ND5), Complex III (Cytochrome b gene, MT-CYB), Complex IV (Cytochrome c oxidase genes, MT-CO1, MT-CO2), and the D-loop region upstream of the mitochondrial tRNA-Pro (MT-TP) gene.