ARMCX5 (armadillo repeat containing X-linked 5) is an X-chrX protein belonging to the GPRASP/ARMCX family, characterized by armadillo-like repeats in its carboxyl-terminal region 1. As a subfamily 1 member, ARMCX5 mediates protein-protein interactions, with several interacting partners identified that regulate cellular physiology 1. ARMCX5 demonstrates disease relevance across multiple pathological contexts. In Alzheimer's disease, ARMCX5 emerged as a key gene associated with M1 macrophage infiltration in the prefrontal cortex, with differential expression validated in both independent datasets and 5XFAD transgenic mice 2. In breast carcinoma, ARMCX5 is enriched in high-grade tumors and associated with potential drug resistance mechanisms (p < 0.0001) 3. Clinically, deletions encompassing ARMCX5 cause the Xq22.1 deletion syndrome, with male patients presenting severe phenotypes including respiratory failure, cleft palate, and neonatal lethality, while heterozygous females exhibit seizures, cleft palate, and developmental delays 4 5. Loss of the 0.35 Mb sub-region containing ARMCX5 is sufficient to cause this syndrome's primary manifestations 4. These findings identify ARMCX5 as a critical regulator of neuroinflammation, tumor biology, and developmental processes, with therapeutic potential in neurodegenerative and malignant diseases.