EXTRA 'Y' CHROMOSOME DOUBLES AUTISM RISK

Study offers 'new explanation' for why autism is more prevalent in men; suggest examining said chromosome closely to identify autism risk factors

An abnormality in one's sex chromosome in the form of an extra Y chromosome has been related with a doubled risk of having autism, according to a study that offered a "new explanation" for why autism is more prevalent in men.

The Y chromosome should be looked at more closely for identifying autism risk factors, researchers said. Sex chromosomes determine an individual's biological sex - men usually carry XY chromosomes in their cells, while women are known to carry XX chromosomes.

However, some individuals carry an abnormal number of X or Y chromosomes, such as XXY or XYY, which is a genetic condition known as 'sex chromosome aneuploidy'.