Phenotypes and epidemiology of rare neurodevelopmental disorders

PhD ceremony: Ms. I.D.C. van Balkom, 16.15 uur, Aula Academiegebouw, Broerstraat 5, Groningen

Dissertation: Phenotypes and epidemiology of rare neurodevelopmental disorders

Promotor(s): prof. H.W. Hoek, prof. R.C.M. Hennekam

Faculty: Medical Sciences

The objective of the research projects in this dissertation was to study autism as it manifests itself within (ultra) rare genetic syndromes; and to examine autism within a specific socio-cultural environment.

Genetically determined syndromes may be characterized by specific dysmorphic features and congenital anomalies, but in clinical practice, the behavioral and cognitive patterns associated with them can be as important. The dissertation provides an overview of these behaviors and describes original research of behavior, cognition and autism in two genetic syndromes. Awareness of such phenotypes provides the clinician with additional tools for diagnosing and differentiating these syndromes. It also allows parents and other caregivers to anticipate and deal with abnormal behaviors.

Autism was studied in Aruba, a distinctive context, whose population has a different sociocultural and ethnic composition than those of Western populations. Prevalence of autism was examined, as well as the association between higher paternal age and increased risk for autism spectrum disorder in offspring. The research focus here was on meaningful differences and similarities between different geographic locations where autism has been studied before.

Understanding neurodevelopmental phenotypes may be useful for the understanding of other disorders that share some of the same behavioral, cognitive and possibly genetic features. Continued studies of these phenotypes will also increase our understanding of significant contributions from social and learning environments, shed more light on individual and group level developmental trajectories, on changes over time, and suggest possibilities to improve outcomes.