Novel insights into congenital surfactant dysfunction disorders by in silico analysis of ABCA3 proteins

Surfactants produced by type Ⅱ alveolar epithelial cells(AT2 cells)are usually present in inclusion organelles called lamellar bodies(LBs).The ATP-binding cassette subfamily A member 3(ABCA3)transporter primarily exists in AT2 cells and is generally considered to be one of the critical regulators of biogenesis of LBs and surfactant metabolism in the lungs[1-4].ABCA3 mutations are the most com-mon cause of congenital surfactant dysfunction disorders(CSDDs),resulting in fatal neonatal respiratory distress and pediatric or adult interstitial lung disease[3,5-7].More than 200 disease-associated ABCA3 variants have been identi-fied in symptomatic infants and children[8].The estimated prevalence of deleterious ABCA3 mutations in the popu-lation is 1/70-1/33,with a predicted disease incidence of 1/20,000-1/4400[7].