Rare, inherited mutations contribute to a significant proportion of autism cases, helping to explain the heritability of the disorder, according to two new studies published today in Neuron.

The genome appears to be littered with so-called ‘hotspots,’ areas that are prone to single-letter mutations, according to research published 21 December in Cell.

Spontaneous, or de novo, mutations are present in about half of individuals with severe intellectual disability who do not have large genetic disruptions, according to two sequencing studies published in November.

Gene expression changes measured in blood may help differentiate children with autism from those without the disorder, suggest two studies published in the past few months.

Of the thousands of DNA variants linked to autism, those that evolved later are the most likely to be harmful, according to a study published 28 November in Nature.

A significant proportion of mutations linked to autism alter proteins that regulate gene expression by modifying the structure of DNA, according to a study published 13 November in Molecular Psychiatry.

Solving the riddle of autism genetics will require looking beyond the growing list of candidate genes to epigenetics and personalized medicine.

By combining pedigree information with sequencing data, a new software tool helps focus on genetic variants likely to be responsible for disease, researchers reported 10 October in Bioinformatics.

A new candidate gene for autism, CHD8, may account for up to 0.4 percent of cases of the disorder, according to research published today in Science. CHD8 is one of six genes identified that together may contribute to one percent of autism cases.

A genetic panel intended to predict the risk of developing autism debuted for clinical use in April, while another is in commercial development and a third was published in Molecular Psychiatry in September. But some experts are concerned, saying the tests are based on preliminary scientific evidence.