Clinical and Molecular Biomarker Studies in RAI1 (Retinoic Acid-Induced 1) -Related Disorders

20 SMS (Smith-Magenis syndrome) patients and 20 PTLS (Potocki-Lupski Syndrome) patients will be enrolled in the study. Additionally, up to 50 healthy controls will be enrolled among family members of patients. All the assessments may be completed during a one-time visit at the hospital which includes an overnight stay for the sleep study for selected individuals. In case all the procedures could not be completed during the one-time visit, subjects may be asked to come again for the remaining procedure. Tests, procedures and samples to be completed or collected: * Demographics will be collected * History and physical examination: A detailed birth, medical, surgical and medication history will be collected as well as seizure and movement disorder histories. Subject chart will be reviewed to complete this data collection. A general physical examination and detailed neurological examination will be performed. * Vitals: blood pressure, temperature, respiratory rate, weight and height will be collected. * Polysomnography/electroencephalography (PSG/EEG): clinician Investigator will determine if subject is candidate for the procedure. A sleep study records the brain electrical waves, the oxygen level in the blood, heart rate and breathing, as well as eye and leg movements. Subject will need to be admitted overnight for the sleep study. The exam is video recorded. * Blood samples: A single blood sample of 15 cc (not exceeding 3 cc per kg) (\~3 teaspoons) will be collected for research purposes. Samples will be kept up to 2 years after the study results are published. * Optional skin biopsy: a skin biopsy from the upper, inner arm, lateral upper thigh, or another area, may be performed for research purposes. A special 3-4 mm (0.12 inches) wide circular tool will be used to remove a small section of skin including deeper layers. A numbing cream or injectable anesthetic (i.e. lidocaine) will be applied to the area before the procedure. Sample will be used to create a cell line. This means that investigators would treat the cells from the sample in a way that allows to grow them in the laboratory. Investigators will then use these cells in research.