The protein missing in fragile X syndrome, FMRP, facilitates the production of hundreds of unusually large proteins, some of which are linked to autism.

More than half of people on the spectrum have four to five other conditions. Which conditions, and how and when they appear, varies from one autistic person to the next.

Autism and intelligence share genetic variants, researchers grow Neanderthal mini-brains and see overlap with autism, and maternal diabetes is an autism risk factor.

Many people with fragile X syndrome show average rates of protein production, challenging a long-held assumption about the condition.

A checklist for fragile X syndrome could help identify people with the condition in low-resource settings, France unveils a plan for early diagnosis and education of children with autism, and virally inserted ‘bar codes’ help track individual neurons.

A modified version of the genetic engineering tool CRISPR may restore expression of the gene mutated in fragile X syndrome.

A semirural Colombian town called Ricaurte is home to the largest recorded genetic cluster of people with mutations linked to fragile X syndrome.

Theory of mind develops surprisingly early, a book publisher doubles down in defense of a controversial author, and false vaccine news gets a correction.

Mice with the mutations linked to tuberous sclerosis make too little protein in their brains — a finding that contradicts a leading theory about the condition.