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  • Print publication year: 2011
  • Online publication date: March 2012

Chapter 34 - Rett syndrome and MECP2 and CDKL5 genotypes

from Section 3 - Symptomatic epilepsy


The neuronal ceroid lipofuscinoses (NCLs) are a group of inherited neurodegenerative disorders. This chapter summarizes the current classification of NCL disorders and their genetic basis. Seizures are often generalized and initially only occasional, becoming more frequent and with the onset of other seizure types within 1-2 years. Most children subsequently found to have tripeptidyl peptidase 1 (TPP1) deficiency and/or mutations in CLN2 present with seizures between the ages of 2 and 4 years. The EEG may show characteristic occipital discharges in response to slow photic stimulation in CLN2 disease, classic late infantile onset and the other NCLs with onset in the late infantile or early juvenile range. Genes CLN1 and CLN2 code for lysosomal enzymes and there is much interest in the possibilities that gene therapy, stem cell therapy, enzyme replacement therapy, and/or substrate reduction might offer families some hope in the future.


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