GRIK5 encodes a glutamate ionotropic receptor kainate type subunit (KA2) that functions as a cation-permeable ligand-gated ion channel activated by L-glutamate and kainic acid 1. This receptor subunit cannot form functional channels independently and requires heteromeric assembly with other kainate receptor subunits, particularly GRIK1 and GRIK2, to produce channel activity 1. The gene is located on chromosome 19.2 and exhibits neural cell-specific expression patterns controlled by a TATA-less, GC-rich promoter with tissue-specific regulatory elements 12. GRIK5 appears to play important roles in vascular biology, particularly in eye vasculature, where reduced expression is associated with decreased blood vessel numbers, compromised vascular integrity, and increased permeability 3. Clinical studies have identified significant associations between reduced GRIK5 expression and various eye diseases, with notable comorbidity between vascular and ocular conditions 3. The gene has been implicated in multiple pathological contexts, including melanoma progression where it serves as a potential diagnostic biomarker 4, and in radiation-induced developmental toxicity where it represents a therapeutic target 5. Additionally, GRIK5 shows dysregulation in cervical cancer and other malignancies, suggesting broader roles in disease pathogenesis 67.