Nrxn1, short for neurexin-1, is a gene encoding presynaptic cell adhesion molecules crucial for synaptogenesis and vesicular neurotransmitter release [5]. Neurexins are involved in the formation, establishment of synaptic structure, and maintenance of synaptic function, playing a vital role in neural connectivity [6].

Heterozygous deletions of Nrxn1 are associated with a diverse spectrum of phenotypes including autism spectrum disorder, attention deficit hyperactivity disorder, intellectual disability, seizures, schizophrenia, mood disorders, and congenital malformations [1]. The clinical features of Nrxn1-related disorders are heterogeneous, mainly consisting of undistinctive facial dysmorphism, intellectual and speech delay, epileptic seizures, and motor dysfunction [2]. Studies on NRXN1 deletions in human brain organoids have shown impacts on molecular pathways related to ubiquitin-proteasome system, alternative splicing, and synaptic signaling in maturing neurons, leading to synaptic dysfunction [4].

In conclusion, Nrxn1 is essential for synaptic function and neural connectivity. Its deletions are linked to multiple neurodevelopmental, psychiatric, and neurological disorders. Research on Nrxn1, especially through models like human brain organoids with deletions, helps in understanding the complex genetic underpinnings of these disorders and may potentially lead to novel therapeutic strategies [3].