Based on limited published evidence, NTN5 encodes netrin 5, a basement membrane and extracellular matrix protein involved in neurogenesis. According to UniProt annotations, it prevents motor neuron cell body migration out of the neural tube and supports substrate adhesion-dependent cell spreading. A transcriptome-wide association study identified NTN5 expression as significantly associated with immunoglobulin G antibody response to human polyomavirus BK infection (P=1.1×10⁻⁹) 12, suggesting an unexpected role in viral immune response, though mechanistic details remain unclear.