Neuropediatrics 2008; 39 - P010
DOI: 10.1055/s-0029-1215779

The Preserved Speech Variant of Rett syndrome: Specificity of atypicality?

PB Marschik 1, A Oberle 2, G Vogrinec 1, F Laccone 3, C Einspieler 1
  • 1Institute of Physiology, Center for Physiological Medicine, Medical University of Graz, Graz, Austria
  • 2Olga-Hospital, Stuttgart, Germany
  • 3Medical University of Vienna, Department for Medical Genetics, Section Genetic Counseling, Vienna, Austria

Introduction: Rett syndrome, predominantly caused by MECP2 mutations begins in seemingly normal 6- to 18-month-old children. The discovery of the MECP2 gene showed that Rett syndrome should be understood as a genetic interference with normal brain development rather than the result of tissue loss or destruction.

Aims: To refer to the developmental course and its early (specific) signs of a rare atypical form of Rett, the Preserved Speech Variant (Zappella Variant).

Subject and methods: One girl with a MECP2 mutation (c.378–43_964delinsGA) meeting clinical criteria for Preserved Speech Variant, was longitudinally observed from 0;6 to 10 years of age. As diagnosis was approved by mutation testing at the girl's age of 4 years, we retrospectively analysed both videos and the clinical history up to this age. Furthermore, we prospectively applied the following methods: the Austrian Rett Survey; behavioural observation in her natural surroundings (video data); Austrian Communicative Development Inventories (ACDI); spontaneous speech samples; active vocabulary test (AWST); language development test (SETK 3–5); test for the reception of grammar (TROG-D).

Results: Episodical events of atypical and stereotyped motor-, prelinguistic and linguistic behaviour increased over time and became predominant at 2 years of age, the onset of regression. Peculiar qualities of general movements, locomotion, cooing and babbling, echolalia, impaired phonological and morphosyntactic abilities, and out of context speech were among the deviant patterns observed.

Conclusions: The comprehensive analyses revealed the presence of early signs of atypical development common to classic Rett that impact on the entire developing neuro-cognitive system. The unique possibility to „look back“ gives new insights into the genetic interference with normal brain development and proves that this variant too, manifests itself within the first months of life.

(FWF – P19581-B02; Lanyar Foundation P325).