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.
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Acknowledgements
We thank the patient and his family for their cooperation. The excellent technical assistance of Reinhilde Thoelen is gratefully acknowledged. KD is a senior clinical investigator and AC an aspirant of the Fund for Scientific Research-Flanders (FWO, Belgium); BT and KV are supported by a grant from the IWT-Vlaanderen. This work is further supported by a grant from Interuniversity Attraction Poles (Belgian State), GOA 2006/12 and a grant from Cure Autism Now (USA).
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Castermans, D., Thienpont, B., Volders, K. et al. Position effect leading to haploinsufficiency in a mosaic ring chromosome 14 in a boy with autism. Eur J Hum Genet 16, 1187–1192 (2008). https://doi.org/10.1038/ejhg.2008.71
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DOI: https://doi.org/10.1038/ejhg.2008.71
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