Abstract
We report the identification of a novel exon, which is referred to as exon 16b, within the cyclin-dependent kinase (CDK)-like 5 (CDKL5) gene that is implicated in the X-linked infantile spasm syndrome and the early-onset seizure variant of Rett syndrome. Interestingly, it is highly conserved in species through evolution, suggesting a potential functional role, but does not display any homology with other referenced sequences. Most importantly, the transcript including this exon is specifically expressed in brain. We suggest that CDKL5 exon 16b should now be considered in the genetic screening of patients presenting with a CDKL5-related disease profile.
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Acknowledgements
We thank Dr Evelyne Bloch-Gallego and Stéphanie Backer for their technical expertize in in situ hybridization, and Yoann Saillour for his technical assistance with the 7500 Real-Time PCR System. This work was supported by the Institut National de la Santé et de la Recherche Médicale (ANR E-RARE EuroRETT Network).
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Fichou, Y., Nectoux, J., Bahi-Buisson, N. et al. An isoform of the severe encephalopathy-related CDKL5 gene, including a novel exon with extremely high sequence conservation, is specifically expressed in brain. J Hum Genet 56, 52–57 (2011). https://doi.org/10.1038/jhg.2010.143
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DOI: https://doi.org/10.1038/jhg.2010.143
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