FHL5 (four and a half LIM domains 5) is a transcriptional coactivator with pleiotropic functions in vascular and neurological disease. In smooth muscle cells, FHL5 regulates vascular disease-associated gene programs through transcriptional control of downstream targets including FOXL1 and FN1, with roles in vascular remodeling and calcium handling 1. FHL5 was identified as a high-confidence susceptibility gene for migraine, with the rs7775721 SNP T allele significantly increasing migraine without aura risk in Han Chinese populations 2. Genome-wide integration studies further confirmed FHL5 as a cross-subtype migraine risk locus 3. Beyond vascular and neurological contexts, FHL5 genetic variants (rs2252816) have been associated with diabetes mellitus risk and disease progression in Chinese populations 4. In cancer, FHL5 was identified as a hub gene in tumor microenvironment signatures predicting clear cell renal cell carcinoma prognosis and immunotherapy response 5. The protein likely functions through binding interactions and transcriptional coactivation mechanisms, though its specific molecular interactions remain incompletely characterized in most disease contexts.