There are two major types of SPs in the lung; 1) The hydrophobic surfactant proteins (SP-B and -C) are responsible for reducing the surface tension and essential for normal lung function (Serrano and Perez-Gil, 2006), and 2) the hydrophilic SPs (SP-A and -D) are responsible primarily for innate immunity and host defense against infections (Wright, 2005; Kishore et al., 2006; Depicolzuane et al., 2021; Floros et al., 2021). The gene discussed is SFTPA1; the disease is infection.