Infantile autism and 47,XYY karyotype.

Dra. Evelyn Kuczynski – Rua Borges Lagoa 1080/908 04038-002 São Paulo SP Brasil. E-mail: [email protected] There is growing evidence that genetic and chromosomal factors are important in the genesis of autism spectrum disorders. The most commonly reported cytogenetic abnormalities are deletions involving chromosomes 7q, 22q13, 2q37, 18q, and Xp, as well as sex chromosome aneuplodies (47,XYY and 45,X/ 46,XY mosaicism). Sex chromosomes seem to be of major importance in the genesis of some cases of autism. We report an adolescent with a diagnosis of infantile autism, in which genetic investigation disclosed the 47, XYY karyotype (also known as “double Y”). Informed consent was obtained with the patient’s parents.