Functional studies in human cells/tissues and C. elegans reveal that all three TMEM17 missense variants impair protein stability and function, confirming TMEM17 as a bona fide ciliopathy gene whose disruption can manifest in a phenotypic spectrum from OFD6/JS to fetal‐lethal MKS (S1 Supplementary Table 2). Here, CPLANE1 is linked to ciliopathy.