An observational study in Smith-Magenis Syndrome (SMS), sponsored by National Human Genome Research Institute (NHGRI). Completed at 1 site in United States. Open to participants aged 1 Month to 115 Years. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by National Human Genome Research Institute (NHGRI) · Observational
This study will examine how a rare disease called Smith-Magenis syndrome (SMS) affects people and how they change over time. SMS is caused by a small chromosome 17p11.2 deletion (missing piece). The syndrome is associated with distinct physical, developmental and behavioral characteristics, but it is not fully understood. To learn more about this disease, a multidisciplinary research team will study:
Patients of all ages with SMS may be eligible for this study. They will be evaluated by a team of medical specialists at the NIH Clinical Center over the course of several days. Parents of patients will be asked to provide copies of past medical records and tests results for review. They will provide a family medical history and information on the child s prenatal, developmental, behavioral and medical histories.
The study may involve the following evaluations: physical, neurological and psychological exams; ear, nose and throat evaluation; speech, language and swallowing evaluation; hearing test; eye examination; imaging studies (e.g., X-rays, ultrasound, MRI); developmental and behavioral assessment; rehabilitation evaluation with gait (walking) analysis; urinalysis, blood, and/or skin cell studies; sleep study; other consultations as required. A tissue sample (blood or cheek swab or skin biopsy) may be taken for genetic studies. To obtain a cheek swab, a small brush is rubbed against the inside of the cheek to wipe off some cells. For a skin biopsy, a small area of skin is numbed with a local anesthetic and a small circle of skin, usually about 1/8 inch, is removed with a biopsy tool. Parents may be asked to complete questionnaires about their child s growth and development, therapies, medications, sleep, development and behavioral concerns. They also may be asked to bring their child to NIH for follow-up visits every 6 months to 3 years, depending on the child s age. The purpose of these visits is to see how the child changes over time and to conduct additional tests.
Parents may also be asked to enroll their child in a SMS Research Registry and provide tissue samples for a SMS Research Core Tissue Bank. The research registry is a confidential database of individuals diagnosed with SMS. Its purpose is to facilitate SMS research initiatives and promote the development of improved treatments for SMS. Enrollment requires completing a 30-minute questionnaire. The tissue bank stores tissue cultures and cell lines created for future SMS research. About 2 teaspoons of blood are drawn from adult patients and 1 to 3 teaspoons from children, depending on their size. Tissue samples can be obtained by skin biopsy or during a scheduled surgical procedure.
This project investigates the clinical manifestations and molecular genetic defects of Smith-Magenis Syndrome (SMS), a rare (1/15,000 1/25,000) clinically recognizable yet often under diagnosed multiple congenital anomaly/intellectual disability (MCA/ID) syndrome (OMIM #182290). The syndrome is characterized by a distinct pattern of minor craniofacial and skeletal anomalies, expressive speech/language delays, psychomotor and growth retardation, and a striking neurobehavioral phenotype that includes a circadian sleep disorder. The majority of cases (\~90%) are due to de novo interstitial deletion of chromosome 17p11.2 that includes the RAI1 (retinoic acid induced 1) gene; however, heterozygous RAI1 mutations account for about 10% of cases. While clinical variability exists, haploinsufficiency of RAI1 (by deletion or mutation) is believed to be responsible for most of the common features that characterize the syndrome.
Individuals with confirmed or clinically suspected SMS, their parents, and/or unaffected siblings will be enrolled in this comprehensive longitudinal natural history study. An NIH interdisciplinary SMS Research Team (SMS-RT) of clinical and basic science researchers, in collaboration with extramural investigators, will conduct comprehensive clinical and molecular analyses to delineate the physiological, developmental (cognitive), behavioral, biochemical, and cellular processes that characterize the syndrome. The protocol aims to: characterize the phenotypic variability, natural history and underlying pathophysiology of SMS; delineate the neurobehavioral phenotype with respect to sleep disturbance, cognition, mood and maladaptive behaviors and sensory processing dysfunction; investigate the physiologic and functional aspects specifically underlying delays in speech/language and motor development; explore genotype/phenotype correlations to identify gene(s) or modifiers that contribute to phenotypic variability; determine potential intervention and therapeutic strategies likely to improve outcome; and evaluate the psychosocial impact of SMS on the family system. Offsite enrollment of two pediatric comparison groups to participate in the Home Assessment of Sleep (HAS) are also enrolled: 1) unaffected siblings/control group; and 2) a DD/ID-comparison group of children with developmental/intellectual disabilities associated with sleep disturbances.
270 studies on the registry are indexed under Learning Disabilities; 62 are open to participants now.
This study's enrollment of 593 is above the median of 150 across 82 observational studies indexed under Learning Disabilities.
Browse Learning Disabilities studies →National Human Genome Research Institute (NHGRI) is the lead sponsor of 203 studies on the registry; 33 are open to participants now.
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Patients and parents and/or siblings of patients with Smith-Magenis Syndrome (SMS) or suspected SMS.
Persons with known or suspected SMS (male/female, all ages, all ethnicities), their parents and/or unaffected siblings are eligible for enrollment. In some cases, a screening evaluation to confirm the diagnosis may occur at NIH and/or via blood samples sent for deletion screening, prior to enrollment. Subjects may be excluded from further participation if the diagnosis of SMS is ruled out after the initial SMS screening evaluation and/or inability to obtain voluntary .
INCLUSION CRITERIA FOR HOME ASSESSMENT OF SLEEP (HAS) DD/MR-SYNDROME COMPARISON GROUP:
Children (male \& female, all ethnicities) less than18 years with a confirmed diagnosis (based on current accepted diagnostic criteria) of a specified developmental disability (DD)/MR-syndrome reported to include sleep disturbance. These include: Prader-Willi syndrome (PWS), Down syndrome (DS), Cornelia deLange syndrome (CDLS), and/or behavioral diagnosis of autism, ADHD or fragile X syndrome.
EXCLUSION CRITERIA FOR HOME ASSESSMENT OF SLEEP (HAS) DD/MR-SYNDROME COMPARISON GROUP:
Failure to meet established/accepted diagnostic criteria and/or inability to obtain voluntary informed consent (i.e. parental consent for child with developmental delay/MR) is reason for exclusion.
INCLUSION CRITERIA FOR SMS RESEARCH REGISTRY AND CORE TISSUE BANK:
Individuals (male \& female, all ages and all ethnicities) with a confirmed diagnosis of SMS \& their parents who voluntarily give informed consent are eligible for inclusion.
EXCLUSION CRITERIA FOR SMS RESEARCH REGISTRY AND CORE TISSUE BANK:
Individuals who do not have a confirmed diagnosis of SMS.
There is no exclusion based on age, gender, ethnicity or any other factor. Decisionally impaired subjects may be enrolled if the parent, legal guardian, or durable power of attorney (DPA) consents; assent will be obtained when deemed appropriate.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Parents and/or siblings of patients with Smith-Magenis Syndrome (SMS) or suspected SMS.
Patients with Smith-Magenis Syndrome (SMS) or suspected SMS.
Natural History
The major objective of this project is to investigate the clinical and molecular manifestations, phenotypic variability, natural history and pathogenesis of Smith-Magenis syndrome (SMS).
Time frame: Ongoing
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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