Based in Glasgow, the Rett Syndrome survey was carried out against a background of eight years' research into the disorder. It was a joint initiative with colleagues in Gothenburg and Cardiff Universities and full co-operation from the National and UK Rett Syndrome Associations who recently produced and circulated teaching videos. The chief aim of the survey was to identify associations, which might assist generic investigation. A description of the classic syndromes was sent to paediatricians in the UK and the Republic of Ireland, followed by the survey protocol. Doctors were invited to report classic and atypical cases, male and female, born on or after 1 February 1975.
104 paediatricians reported 225 identified cases at the time of writing 22 awaited confirmation. Ten cases were born before 1975 leaving 215 cases so far identified within the age limits. Among 169 who were sufficiently described, classical Rett syndrome acquitted for 150 880%0. 114 family histories had been received. After five years of age, when the diagnosis usually become evident, number reported in each year fluctuated between 12 and 25, with 17 born in 1975. Patchy reporting and a steady flow of new report suggest that many cases are still being overlooked.
This survey has so far increased to 383 the total number of cases known at all ages in the UK and the Republic of Ireland. 91 were born before 1975, the oldest being 42 years. Among the 152 family trees, associations have already been identified which are helping to direct genetic research. These include concordant monozygotic twins (one pair), discordant dizygotic twins, male/female (one pair) and female/female (one pair). One classic Rett syndrome girl is reported to have an atypical but Rett-like maternal aunt. No male has been found with classic Rett Syndrome but several families with profoundly handicapped, non-Rett children of both sexes are being investigated. Recurring schizophrenia and psychosis have been reported in a proportion of families. The early results of the survey indicate the prolonged health y survival to be expected in Rett Syndrome and suggest a prevalence in the order of 1 in 10,000 girls, or 1 in 10 girls and women suffering from profound mental and physical disability. The genetic origin of the disorder and the exclusive appearance of the phenotype in females are indicated.
Dr A Kerr - Quarrier's Homes Bridge of Weir, Remfrewshire PA1 3SA