Ninety-nine cases of Rett syndrome (RTT) diagnosed clinically (age range 3 years 6 months to 29 years 9 months) were evaluated for the ability of language. The presence of meaningful words, vocabularies, and ages at the start and disappearance of speech were assessed. Phenotype/genotype correlation was evaluated in 22 cases in whom mutations of the genes of methyl-CpG-binding protein 2 (MECP2) existed. Fifty-five cases (55.5%) could speak some words, and of them eight cases (14.5%) spoke two-word sentences. No case had more than 40 words. The vocabularies were mainly bilabial words, known as the characteristics of the initial words in normal children. They began to utter a word between 12 and 48 months, and most of them (85.4%) before 20 months. Those who spoke two-word sentence(s) began to utter a word earlier (10.4±3.7 months) than others (17.1±9.8 months). Thirty-three cases lost their word(s) in 12–36 months. Among 22 gene-proven cases two cases with mutation of R133C and two cases with R294X had word(s), but another two cases with T158M had not. In RTT a delay in the neuronal systems involved in normal speech development was suggested and its severity seemed to depend on the loci of mutation.
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Brain and Development
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
- Uber ein zerebral-atrophisches Syndrome bei Hyperammonemie.Wien Med Wochenschr. 1966; 116: 723-726
- A progressive syndrome of autism, dementia ataxia, and loss of purposeful hand use in girls: Rett's syndrome: report of 35 cases.Ann Neurol. 1983; 14: 471-479
- The Rett girls with preserved speech.Brain Dev. 1992; 14: 98-101
- The preserved speech variant: a subgroup of the Rett complex: a clinical report of 30 cases.J Autism Dev Disord. 1988; 28: 519-526
- Locomotion in late infancy and development of higher cortical function at later ages.in: Milivoj Veličković P. New Developments in Child Neurology. Monduzzi Editore, Bologna (Italy)1998: 27-30
- Preserved speech variant is allelic of classic Rett syndrome.Eur J Hum Genet. 2000; 8: 325-330
- Mutational analysis of the MECP2 gene in Japanese patients with Rett syndrome.J Hum Genet. 2000; 45: 231-236
© 2001 Elsevier Science B.V. Published by Elsevier Inc. All rights reserved.