Children, especially girls, with autism who have older fathers are more likely than those with younger fathers to be the only child with the disorder in their family, according to a new study published 16 December in Autism.

In families that have more than one child with autism, the middle children, particularly those born second, have a higher risk of developing autism than other children in the family, according to a study published 19 October in PLoS One. In families that have only one child with autism, however, risk of the disorder rises with each additional birth, the study found.

The offspring of older male mice are 16 times more likely to harbor a spontaneous copy number variation — a deletion or duplication of genetic material — than are the offspring of young males, according to a new study.

What’s known about the genetics of autism supports the ‘snowflake’ hypothesis — that the molecular underpinnings of disease are essentially unique from individual to individual — says human geneticist Brett Abrahams.

A large population survey in England finds many adults with undiagnosed autism, bringing the disorder’s prevalence in adults to 1 in 100, approximately the same rate as in children, according to a report in May in the Archives of General Psychiatry.

Good mouse models of autism, and accurate tests to assay their phenotypes, are key to both narrowing down a cause and developing effective treatments, argues expert Jacqueline Crawley.

A child in Australia is more likely to have autism if he or she is the first-born, is born to a woman who is older than 40 years, or belongs to a family of higher socio-economic status, according to a study published in March in PLoS One.

As awareness about autism has spread in California, lower-income families have become more likely to seek a diagnosis of autism, says a new study.

Children with autism and those who have fathers older than 31 both have lower-than-normal levels of proteins that regulate other genes, according to a study published in February in PLoS One.

A man’s risk of fathering a child with autism begins to rise at age 30 and significantly increases after age 50, according to a report published online 30 November in Molecular Psychiatry.