The CHRND gene encodes the delta subunit of the nicotinic acetylcholine receptor (nAChR), a ligand-gated ion channel critical for neuromuscular signal transmission. nAChRs are pentameric proteins composed of α, β, γ (or ε in adults), and δ subunits, forming a channel that depolarizes the postsynaptic membrane upon acetylcholine binding, triggering muscle contraction. The δ subunit (CHRND) is essential for receptor assembly and function. Antibodies targeting CHRND are valuable tools for studying neuromuscular junction disorders, such as congenital myasthenic syndromes (CMS) or autoimmune myasthenia gravis (MG), where disrupted receptor activity causes muscle weakness. In research, CHRND antibodies are used in techniques like Western blot, immunohistochemistry, or flow cytometry to localize or quantify receptor expression, assess developmental changes (e.g., γ-to-ε subunit switch), or investigate disease mechanisms. Autoantibodies against CHRND in MG block receptor function, impairing synaptic signaling. Additionally, CHRND mutations linked to CMS highlight its role in receptor stability and ion conductance. Studying CHRND antibodies aids in understanding receptor biology, diagnosing neuromuscular pathologies, and developing targeted therapies.