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Chapter 8204intellectual disability.10 Prevalence rates that seem to be higher compared to the general population and to adults with an intellectual disability, included for example Parkinson’s disease, astigmatism, posterior embryotoxon and retinal vascular tortuosity,2, 3, 11-13 although not all of these conditions have been studied well in other GNDs. In the following paragraphs, the most important results and recommendations for clinical practice and future studies in adults with 22q11.2DS are discussed per study topic.Parkinson’s disease In chapter 3, it was found that adults with 22q11.2DS have an increased risk of Parkinson’s disease; much higher compared to what has been reported in the general population.2 This suggests that hemizygosity of one or more genes within the typically deleted 22q11.2 region convey an increased risk of Parkinson’s disease. Future study of these genes and underlying mechanisms may provide insights into the pathophysiology of Parkinson’s disease in 22q11.2DS, that may possibly also be of importance for the study of idiopathic Parkinson’s disease. Other main findings included a sharp increase in Parkinson’s disease after the age of 50 years, with motor onset about one decade earlier, and the equal prevalence of Parkinson’s disease between males and females with 22q11.2DS, different from what has been reported in the general population and previous studies of adults with 22q11.2DS.2, 14 These insights do not only provide directions for future research but are also of clinical relevance. Based on these findings and the impact of Parkinson’s disease on a person’s life, standard neurological assessments seem warranted after the age of 40 years to screen for parkinsonian (motor) features. Early detection of Parkinson’s disease can be beneficial,15 since it allows for early treatment with anti-parkinsonian medication which was found to be able to reduce motor symptoms in the majority of individuals with 22q11.2DS.14Hearing loss and otolaryngological findingsIn chapter 4, it was found that the majority of adults with 22q11.2DS had hearing loss, mostly of the higher frequencies, while only ~30% of adults were known to have hearing loss prior to the routine audiometric screening. Hearing loss started at a much younger age compared to the general population, though with a pattern suggestive of age-related hearing loss