Short-chain acyl-CoA dehydrogenase (SCAD), encoded by the Acads gene, functions in the mitochondrial β-oxidation of saturated
short-chain fatty acids.
SCAD deficiency results in
mitochondrial dysfunction, which is one underlying biological mechanism of
chronic obstructive pulmonary disease (
COPD) pathogenesis. In this case-control study, we aimed to examine the effects of Acads gene polymorphisms on the susceptibility to
COPD. A total of 16 tagging single-nucleotide polymorphisms (SNPs) in Acads gene region was identified and genotyped in 646 unrelated ethnic Chinese Han individuals including 279 patients with
COPD and 367 healthy controls, their allelic and genotypic associations with
COPD were determined by different genetic models. Furthermore, we estimated the linkage disequilibrium and haplotypes from these tested variants and determined the effects of haplotypes on the risk of
COPD. The allelic and genotypic frequencies of SNPs rs2239686 and rs487915 in Acads gene were significantly different between
COPD patients and controls, no statistically significant results were observed for other SNPs. Minor alleles A of rs2239686 and T of rs487915 were associated with a decreased pulmonary function and an increased
COPD risk in a dominant manner. Functional analysis indicated that the risk allele A of rs2239686 could increase Acads expressions and the intracellular
reactive oxygen species content. Haplotype analysis revealed that the haplotypes CTCCT in block 2 (rs3794216-rs3794215-rs34491494-rs558314-rs7312316) as well as GC in block 3 (rs2239686-rs487915) were protective against
COPD, while haplotypes CTCGC in block 2 and AT in block 3 exhibited significant associations with the increased susceptibility to
COPD. Our results suggest that Acads gene could potentially be a risk factor of
COPD and thus its genetic variants might be as genetic
biomarkers to predict the
COPD susceptibility.