NR1H4 and Leber congenital amaurosis: As we know, LCA is a secondary BA and can activate multiple transcription factors [such as farnesoid X receptor (FXR)] and BA receptors (such as Takeda G-protein coupled receptor 5 (TGR5)] (Zhang et al., 2019a; Hui et al., 2020; Liang et al., 2020).