A microexon regulatory code reveals autism-linked genetic variation.

Hundreds of new microexons, many with neuron-specific patterns, are identified, and their splicing is predicted to be altered by autism-linked genetic variants.

• Why it matters: Understanding how genetic variation affects microexon splicing is crucial because microexon disruption is linked to autism, yet the full landscape and regulatory mechanisms remain unknown.
• What they did: The study used extensive transcriptome profiling to discover microexons, applied machine learning to define a sequence code for neuronally spliced microexons, and identified variants predicted to alter splicing in autism-affected individuals.
• The result: The findings reveal an expanded set of microexons and their regulatory code, with rare variants in autism patients predicted to impact microexon splicing, converging on autism-related genes and functions.