TTC7A (tetratricopeptide repeat domain 7A) is a critical regulator of intestinal homeostasis and immune function. Functionally, TTC7A serves as a core component of a protein complex required to localize phosphatidylinositol 4-kinase (PI4K) to the plasma membrane, thereby regulating phosphatidylinositol 4-phosphate synthesis 1. The protein bridges PI4KA to EFR3B and HYCC1 through direct protein-protein interactions, controlling actin cytoskeleton dynamics and lymphocyte migration through the TTC7A/PI4KIIIα/phosphoinositide 3-kinase/AKT/RHOA axis 2. Mechanistically, TTC7A deficiency impairs phosphoinositide signaling, leading to dysregulated actin dynamics, reduced cell deformability, and increased DNA damage accumulation in immune cells 2. Clinically, biallelic TTC7A mutations cause Gastrointestinal Defects and Immunodeficiency Syndrome 1 (GIDID-1), a severe autosomal recessive disorder 3. Patients present with heterogeneous phenotypes including very early-onset inflammatory bowel disease, multiple intestinal atresia, combined immunodeficiency, and apoptotic enterocolitis 4. Loss-of-function variants correlate with more severe disease and reduced survival (median 9 months), while missense variants associate with milder phenotypes (median 33.5 months) 5. TTC7A deficiency causes excessive intestinal epithelial apoptosis via elevated caspase 3/7 activity 6. Treatment options are limited; leflunomide, a drug that reduces apoptosis via AKT/XIAP activation, shows promise in preclinical models 6, while Rho-kinase inhibitors represent potential therapeutic approaches 7.