An X-linked long non-coding RNA, PTCHD1-AS, and the core features of autism.

Abstract

There are around 100 genes or copy-number variations used in genetic testing for autism spectrum disorder (ASD)^1,2. The established genes are protein coding, and the associated phenotypes usually extend beyond sociobehavioural traits seen in autism, including cognitive/medical complexities and attention deficit hyperactivity disorder (ADHD)^3,4. We examined whole-genome sequencing data in cases of ASD (9,349) and controls (8,332) and identify 27 male individuals with ASD with X-chromosome microdeletions that implicate the long non-coding RNA PTCHD1-AS as an ASD-susceptibility gene (odds ratio = 2.56, P = 0.01). Two Ptchd1-as-knockout mouse models, which were created by disrupting/deleting the evolutionarily conserved exon 3, show ASD-like features in male mice, including increased repetitive behaviours and impaired social behaviour and communication without cognitive comorbidities or ADHD-like behaviours. Hippocampus-dependent synaptic function, complex learning and locomotor activity are unaffected in knockout mice. Native nuclear-enriched mouse Ptchd1-as showed sustained expression from postnatal day 7 onwards in the dorsal striatum, a predominantly GABAergic brain region that is implicated in ASD⁵. Multi-omics analysis revealed transcriptomic alterations in striatal oligodendrocytes, astrocytes and neurons impacting myelination and synaptic plasticity. Disrupting Ptchd1-as led to reductions in conventional protein kinase C (cPKC) isoforms, altered SRC and GSK-3α/β phosphorylation and enhanced striatal synaptic plasticity (long-term potentiation and long-term depression). Together, these findings implicate striatal molecular and circuit-level dysregulation through PTCHD1-AS in ASD aetiology.