1. ¹Department for Human Genetics, Laboratory for Biochemical Neuroendocrinology, University of Leuven, Belgium
2. ²Division of Clinical Genetics, Center for Human Genetics, University of Leuven, Belgium
3. ³Department of Clinical Genetics, Academic Hospital Maastricht, Research Institute Growth and Development (GROW), Maastricht University, The Netherlands
4. ⁴Department for Human Genetics, Laboratory for Molecular Oncology, University of Leuven, Belgium
5. ⁵Department of Child Psychiatry, University of Leuven, Belgium

Correspondence: Professor K Devriendt, Center for Human Genetics, University of Leuven, Herestraat 49, B-3000 Leuven, Belgium. Tel: +32 16 34 59 03; Fax: +32 16 34 60 51; E-mail: koenraad.devriendt@uzleuven.kuleuven.be

Received 12 September 2007; Revised 22 February 2008; Accepted 7 March 2008; Published online 16 April 2008.

Abstract

We describe an individual with autism and a coloboma of the eye carrying a mosaicism for a ring chromosome consisting of an inverted duplication of proximal chromosome 14. Of interest, the ring formation was associated with silencing of the amisyn gene present in two copies on the ring chromosome and located at 300 kb from the breakpoint. This observation lends further support for a locus for autism on proximal chromosome 14. Moreover, this case suggests that position effects need to be taken into account, when analyzing genotype–phenotype correlations based on chromosomal imbalances.