PLOS Genetics study maps distinct synaptic and sleep effects of NLGN3 autism variants in Drosophila

Research published in PLOS Genetics by Townsley, Andrews, Srivastav, Jangam, Hannan, Kanca, Marcogliese, Yamamoto, and Wangler examines how distinct variants in NLGN3 — an X-linked gene encoding neuroligin-3 — affect synaptic function and sleep behaviour using Drosophila melanogaster as a model organism.

NLGN3 was first identified as a risk gene for autism spectrum disorder (ASD). The canonical p.R451C variant, which has been the focus of extensive prior investigation, was studied alongside other reported patient variants, including de novo changes identified in heterozygous females and hemizygous males. The study finds that different NLGN3 variants produce functionally distinct consequences at synapses and result in separable changes in sleep behaviour in the fly model — suggesting that variant-level resolution matters when characterising the biology of NLGN3-associated neurodevelopmental conditions.

The investigators note that most reported NLGN3 variants arise in males who have inherited them from an unaffected mother, though de novo variants have been described in both sexes. The use of Drosophila enables precise genetic manipulation and high-throughput phenotyping, though findings require subsequent validation in mammalian systems before conclusions about human neurobiology can be drawn.

The paper contributes to the broader effort to move beyond gene-level to variant-level functional characterisation in ASD research, which has implications for understanding genotype–phenotype relationships in neurodevelopmental genetics.