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Background: Determining the aetiology of intellectual disability (ID) enables anticipation of specific comorbidity and can thus be beneficial. Blood sampling, however, is considered stressful for people with ID. Our aim was to evaluate the feasibility of a non-invasive screening technique of nine microdeletions/duplications among adults with ID of unknown aetiology. Methods: In a random sample of 300 adult clients of Dutch ID services without an aetiological diagnosis, DNA was collected on site using oral swabs. Multiplex Ligation-dependent Probe Amplification was applied to screen for nine microdeletions/duplications related to ID syndromes (Williams 22q11-deletion, 1p-deletion, Miller-Dieker, Smith-Magenis, Prader-Willi, Alagille, Saethre-Chotzen and Sotos syndrome). Results: Feasibility: prior to the consent procedure, for 2.1% (10/471 eligible participants), the method was considered undesirable. In 0.7% (2/300 participants) oral swabs failed because of resistant behaviour, while in 16.1% (48/298 swabs) analysis was unsuccessful because of insufficient amounts of DNA. A repeated attempt yielded an equal success rate. Outcome: Microdeletions were diagnosed in four participants: 22q11 deletion (n = 2), 5q35 deletion (Sotos syndrome) (n = 1) and 1p deletion (n = 1). One participant had a duplication of the Prader-Willi Region (15q11-13) owing to mosaicism of a supernumerary marker chromosome (15). Conclusions: Oral swabs are a feasible method for DNA sampling in adults with IDs. A diagnosis could be made in five out of 275 people with ID of unknown aetiology. After screening, in the total population sample (n = 620), the prevalence of syndromes associated with the microdeletions/duplications studied was at least 2.3% (95% confidence interval 1.1-3.4%). (Contains 4 tables.)

A low energy particle confined by a horizontal reflective surface and gravity settles in gravitationally bound quantum states. These gravitational quantum states (GQS) were so far only observed with neutrons. However, the existence of GQS is predicted also for atoms. The GRASIAN collaboration pursues the first observation of GQS of atoms, using a cryogenic hydrogen beam. This endeavor is motivated by the higher densities, which can be expected from hydrogen compared to neutrons, the easier access, the fact that GQS were never observed with atoms and the accessibility to hypothetical short-range interactions. In addition to enabling gravitational quantum spectroscopy, such a cryogenic hydrogen beam with very low vertical velocity components-a few cm s - 1 , can be used for precision optical and microwave spectroscopy. In this article, we report on our methods developed to reduce background and to detect atoms with a low horizontal velocity, which are needed for such an experiment. Our recent measurement results on the collimation of the hydrogen beam to 2 mm, the reduction of background and improvement of signal-to-noise and finally our first detection of atoms with velocities < 72 ms - 1 are presented. Furthermore, we show calculations, estimating the feasibility of the planned experiment and simulations which confirm that we can select vertical velocity components in the order of cm s - 1 ., (© The Author(s) 2024.)