Public defence: Mari Wold Henriksen Mari Wold Henriksen at Institute of Clinical Medicine will be defending the thesis “Rett syndrome: Clinical and genetic aspects” for the degree of PhD (Philosophiae Doctor).

Image may contain: Clothing, Chin, Forehead, Smile.

Trial Lecture – time and place

See Trial Lecture.

Adjudication committee

  • First opponent: Senior Consultant Anne-Marie Bisgaard, Rigshospitalet, Denmark
  • Second opponent: Professor Jon Sverre Skranes, Norwegian university of science and technology (NTNU)
  • Third member and chair of the evaluation committee: Professor Bjørnar Hassel, Faculty of Medicine, University of Oslo

Chair of the Defence

Professor Ole Richard Haavet, Faculty of Medicine, University of Oslo

Principal Supervisor

Professor Ola H. Skjeldal, University of Gothenburg


Rett syndrome (RTT) is a neurodevelopmental disorder which almost exclusively affects girls. In its classic form, it is characterized by an apparently normal development in the first 6 to 18 months of life, followed by loss of acquired skills. The most affected skills are language and purposeful hand use. A majority will develop epilepsy, scoliosis and other comorbidities.

Our overall aim was to describe the genotypic and phenotypic variation in the Norwegian RTT population, and the development of clinical features in different phases of life. The methods included clinical examinations, interviews with caregivers, review of medical journals and genetic workup.

Although RTT is mainly caused by a mutation in MECP2, a not insignificant number of individuals with RTT do not have such a mutation. In this study, 88% (n=74) of individuals with RTT had a mutation in MECP2. The remaining had mutations in one of five other genes, or no identified pathological mutation at all. Significant differences between individuals with MECP2 mutations and those without were observed; especially interesting was the higher prevalence of early onset epilepsy in individuals without a MECP2 mutation.

Regardless of mutation, epilepsy continued to be a major concern into adult life, with more frequent seizures than in adolescence, and high prevalence of bilateral tonic-clonic seizures. The mean global severity of RTT increased from children/adolescents to young adults, but it then stabilized in adulthood. In general, the main health issues examined showed stability in prevalence, regardless of age. 

Overall, the study shows that adults with RTT have many of the same health challenges as children with RTT, and should therefore be offered the same follow-up in the health care system. In addition, the proven differences between individuals with and without a mutation in MECP2 indicate that the current diagnostic criteria may include individuals with a different disorder under the RTT umbrella.

Additional information

Contact the research support staff.

Published Feb. 14, 2020 10:52 AM - Last modified Feb. 18, 2020 1:53 PM