SIPA1L2 (signal induced proliferation associated 1 like 2) functions as a GTPase activator with roles in neurological disease susceptibility and cellular regulation. The protein exhibits GTPase activator activity and localizes to glutamatergic synapses, suggesting involvement in synaptic signaling pathways 1. SIPA1L2 variants show significant associations with Parkinson's disease risk in East Asian populations, where the T allele at rs10797576 serves as a risk factor (OR=1.484) 1. However, this association appears population-specific, as studies in Taiwanese and Iranian populations show conflicting results 23. In peripheral neuropathy, SIPA1L2 acts as a genetic modifier of Charcot-Marie-Tooth disease type 1A (CMT1A), with deletion studies in mouse models demonstrating effects on muscular endurance and myelin thickness 45. Gene expression analyses suggest SIPA1L2 involvement in cholesterol biosynthesis pathways 4. Additionally, SIPA1L2 is targeted by miR-21 in autophagy regulation and by miR-4533 in gallbladder cancer, where its downregulation correlates with disease development 67. The gene also shows differential expression in reproductive tissues associated with recurrent pregnancy loss 8.