TMEM107 is a transmembrane protein localized to the ciliary transition zone that plays a critical role in ciliogenesis and primary cilia protein composition 1. During cilia formation, TMEM107 regulates the localization of MKS complex proteins to the ciliary transition zone and controls overall ciliary protein content 1. TMEM107 functions as a negative regulator of Hedgehog (Hh) signaling; loss of TMEM107 expression leads to ectopic activation of the SHH pathway and upregulation of GLI1 target genes 23. TMEM107 is essential for proper eye development, as Tmem107-deficient mice exhibit anophthalmia and microphthalmia with impaired retinal differentiation 2. TMEM107 deficiency in retinal organoids results in loss of primary cilia and cyst formation 2. Biallelic TMEM107 mutations cause Meckel-Gruber syndrome (MKS13) and Orofaciodigital syndrome (OFD16), both ciliopathies characterized by developmental abnormalities 41. Patients and animal models with TMEM107 mutations display marked ciliogenesis defects, abnormal cilia length, polydactyly, and reduced ciliated cell numbers 14. Additionally, TMEM107 variants are associated with congenital heart defects, particularly heterotaxy, through its role in ciliogenesis 5. Loss of TMEM107 in cancer cells promotes epithelial-mesenchymal transition and invasion through Hh pathway activation, suggesting tumor-suppressive functions 3.