NLGN1 (Neuroligin 1): NLGN1 is a measure that indicates the presence and function of a key protein in the nervous system — Neuroligin 1, which is encoded by the NLGN1 gene. It plays an essential role in the formation and regulation of synapses, supporting synaptic specialization, strength, and plasticity. NLGN1 is crucial for learning, memory, and overall brain function, and has been a significant focus in research on autism spectrum disorders and other neurodevelopmental conditions.