BMP4 and myopia: Here, four novel BMP4 truncation variants exclusively segregated with pathologic myopia in eight patients from four unrelated families suggests a novel bidirectional role of BMP4 in the normal and abnormal development of the eye, since most BMP4 variants were associated with microphthalmia-related disorders based on Human Gene Mutation Database (HGMD) database from previously studies (Bakrania et al., 2008; Hayashi et al., 2008; Reis et al., 2011; Lumaka et al., 2012; Huang X. et al., 2015; Blackburn et al., 2019; Nixon et al., 2019; Thanikachalam et al., 2020; Figure 2D).