Down Syndrome

Down syndrome (DS) is typically caused by an extra chromosome 21 in the cell nucleus (trisomy 21, or T21). T21 is both the most common cause of genetically defined intellectual disability and the earliest documented cause of Alzheimer's disease (AD)-type pathology. Currently, all presymptomatic individuals with DS are classified as having 'Stage 0' DS-associated AD (DSAD). DSAD pathology evolves inexorably, with virtually all individuals with DS developing AD pathology by age 40, and approximately 50% meeting clinical dementia diagnosis criteria at 55 years of age. This study will test the hypothesis that the FDA-approved AD drug memantine, at higher-than-standard doses, may be effective as a cognitive enhancer in young adults with DS. The primary goal of this phase 1b clinical trial will be the assessment of the safety and tolerability of three memantine doses in persons with DS. In addition, we will assess the effect of this drug on cognitive test scores and plasma biomarkers of AD in the study participants. Finally, we will also investigate steady-state plasma levels of memantine and the time course of memantine plasma levels after a single dose in the study participants (pharmacokinetics, or PK). The data generated through this phase 1b study will provide the essential safety, PK, and preliminary efficacy signals required to advance a phase 2 trial evaluating high-dose memantine as a first-in-class therapeutic strategy in DS.

The purpose of this study is to assess whether oxygen supplementation during sleep improves working memory and other clinical and patient-reported outcomes among children who have Down Syndrome (DS) with moderate to severe Obstructive Sleep Apnea (OSA).

Down syndrome (DS), the most common genetic cause of intellectual disability, is associated with widespread organ dysfunction, including abnormalities in the autonomic nervous system (ANS). The ANS regulates critical functions such as heart rate (HR) and blood pressure (BP), both essential for maintaining homeostasis and supporting physical activity. Individuals with DS often exhibit blunted HR responses to exercise-typically \~30 beats per minute below expected levels-suggesting reduced sympathetic nervous system (SNS) activity. The SNS governs rapid changes in HR and BP during stress by releasing catecholamines: epinephrine (from the adrenal medulla) and norepinephrine (from sympathetic nerve endings). Despite its importance, SNS function has not been comprehensively assessed among individuals with DS. This study addresses a critical knowledge gap by evaluating SNS responses to physiological stressors in individuals with DS. The investigators will measure beat-to-beat HR and BP, along with plasma catecholamine levels, in response to sympathetic activation, comparing individuals with DS to age- and sex-matched controls. Understanding the mechanisms of SNS dysfunction in DS is vital, as it likely underlies reduced exercise capacity and contributes to broader clinical challenges. These insights may guide targeted interventions to improve cardiovascular function, physical capacity, and overall quality of life in this understudied population.

The overall objective of this randomized clinical trial is to test the effectiveness of a personalized approach to the surgical treatment of OSA in children with Down syndrome (DS).The estimated prevalence of obstructive sleep apnea (OSA) in children with DS ranges from 45-83%, compared to 1-6% in the general pediatric population. Untreated OSA in children has been associated with daytime sleepiness, cognitive or behavioral problems, and cardiovascular complications, all which are common in children with DS. Adenotonsillectomy (AT) is the first line treatment for OSA in children, however, most large studies of AT outcomes have excluded children with DS. Available evidence demonstrates that AT is far less effective in children with DS than in the general pediatric population, with 48 to 95% of children with DS having persistent OSA after AT. Medical treatments such as positive airway pressure (PAP) therapy are frequently inadequate or poorly tolerated in this population, so many children with DS and OSA remain untreated. Drug-induced sleep endoscopy (DISE) enables direct observation of the sites and patterns of obstruction during sedated sleep using a flexible endoscope passed through the nose into the pharynx. DISE was developed to guide surgical decisions in adult OSA, and in recent years has also been used to design personalized surgical interventions in children. Using this DISE Rating Scale, the investigators have demonstrated that children with DS are more prone to tongue base and supraglottic obstruction than non-DS children, suggesting the need for more personalized surgical treatments that are tailored to the common sources of obstruction in this population. Several small case series demonstrate that DISE-directed surgery can be effective in treating OSA in children with DS. However, because there have been few prospective studies and no randomized trials comparing different treatment options in this population, there remains uncertainty about whether such a personalized approach leads to superior outcomes compared to the first line AT. It is the investigators' hypothesis that personalized DISE-directed surgery that uses existing procedures to address specific fixed and dynamic anatomic features causing obstruction in each child with DS will be superior to the current first line approach of AT. This novel approach may improve OSA outcomes and reduce the burden of unnecessary AT or secondary surgery for persistent OSA after an ineffective AT.

This cross-sectional study aims to evaluate the hematological profile and determine the frequency and pattern of hematological abnormalities in children with numerical chromosomal disorders attending the Pediatric Department of Assiut University Children's Hospital.

Down syndrome is the most common genetic cause of intellectual disability. People with Down syndrome often have obstructive sleep apnea (OSA), a condition where people have difficulties with breathing while asleep. OSA can lead to poor sleep, worse quality of life, behavior problems and more difficulties with thinking ("cognitive impairment"). Current treatments for OSA in people with Down syndrome are not very effective or require surgery. The combination of 2 medications, atomoxetine and oxybutynin ("ato-oxy") is a promising treatment for OSA in people with Down syndrome, but ato-oxy does not work for everyone with Down syndrome. Similarly, oxygen is effective for OSA in some people, but does not work for everyone. This study will evaluate the use a precision medicine approach to increase the effectiveness of OSA treatment in people with Down syndrome. The study will compare two groups. In the first group, everyone will be treated with ato-oxy. In the second group, a precision medicine approach will be used to assign participants to either ato-oxy or oxygen therapy, based on the specific reasons they have OSA. The research team will enroll 200 children (age 6-17 years old) and adults with Down syndrome and OSA from five sites across the country. Half of participants will randomly receive ato-oxy while the other will receive either oxygen or ato-oxy dependent upon which treatment would be expected to work better for them. The research team will measure OSA severity, quality of life, behavior and cognition at the start of the study and after 12 months of treatment for every participant. The study will also track any treatment side effects for each treatment group.

The specimen collection is designed for the purpose of the development of a noninvasive prenatal test for T21.

This protocol describes a phase 2, double-blind, randomized, placebo-controlled clinical trial for Janus kinase (JAK) inhibition in Down syndrome (DS). This trial will evaluate the safety and efficacy of a 6-month treatment with the JAK1/3 inhibitor tofacitinib in individuals ages 6-22 (inclusive) with DS. There will be two main arms for this study: a treatment arm and a placebo control arm. Participants will be randomized into the treatment or placebo arm. Those completing 6 months in the placebo arm may be eligible to participate in a cross-over, open-label extension arm to receive 6 months of tofacitinib treatment. Participants will be evaluated during a Screening visit to determine eligibility, complete a Baseline visit if eligible, and be monitored via safety clinical laboratories and in-person evaluations by study doctors at 1 month, 3 months (mid-point visit) and 6 months (endpoint visit). An interim analysis of safety will be completed by an independent Data and Safety Monitoring Board (DSMB) after 40 participants have completed 6 months of treatment or placebo (20 in each arm).

This phase II trial studies the effect of nivolumab in combination with blinatumomab compared to blinatumomab alone in treating patients with B-cell acute lymphoblastic leukemia (B-ALL) that has come back (relapsed). Down syndrome patients with relapsed B-ALL are included in this study. Blinatumomab is an antibody, which is a protein that identifies and targets specific molecules in the body. Blinatumomab searches for and attaches itself to the cancer cell. Once attached, an immune response occurs which may kill the cancer cell. Nivolumab is a medicine that may boost a patient's immune system. Giving nivolumab in combination with blinatumomab may cause the cancer to stop growing for a period of time, and for some patients, it may lessen the symptoms, such as pain, that are caused by the cancer.

The Executive Function Play Opportunities (EXPO) study is a sequential, multiple assignment, randomized trial (SMART) evaluating adaptive caregiver-mediated intervention pathways for improving executive function (EF) in children with Down syndrome (DS). At baseline, participants will be randomized in a 1:4 ratio to receive either a delayed-treatment control condition or the EXPO intervention. After 4 weeks of standard EXPO intervention in stage 1, participants in the EXPO condition will be assessed for response to the intervention based on prespecified criteria for improvement in laboratory-based EF performance. Early responders will continue with the standard EXPO intervention in stage 2. Slower responders will be randomized to either the EXPO Extended or EXPO Foundations pathway. All participants will complete laboratory and parent-report measures of EF immediately post-intervention and 3 months later. Participants in the delayed-treatment control condition will complete the same assessments as the EXPO groups and will be offered the EXPO intervention after completion of the 3-month follow-up.

This study will pilot a newly developed Syntactic-Semantic Visual Configuration Intervention (SSVCI) designed to help Urdu-speaking children with language impairment improve their ability to understand and produce phrases and sentences. The intervention was developed through extensive literature review, expert recommendations, and the structure of the Urdu language to ensure that it is appropriate for children in Pakistan. Before pilot testing, experts in speech-language pathology and Urdu linguist according to the inclusion criteria reviewed the intervention material to evaluate whether the activities are relevant, culturally appropriate, and representative of the language skills being taught. Feedback from children and caregivers was also be used to in the first phase of need assessment, before the intervention material was finalized. The pilot study will include 20 children aged 6 to 12 years, including 10 children with language impairment and 10 children with typical language development. Participants will be recruited from selected schools, hospitals, and special education centers in Islamabad. Children with language impairment conditions , with primary diagnosis of autism spectrum disorder, hearing impairment, cerebral palsy, or Down syndrome, provided they meet the study eligibility criteria will be included. Participants will complete language assessments before taking part in the intervention activities. These assessments will measure language skills such as sentence formation, understanding of spoken language, and narrative abilities. Information collected during the pilot study will help researchers determine whether the intervention materials are clear, practical, culturally appropriate, and suitable for use in a larger clinical trial. Findings from this study will also be used to refine the intervention by identifying activities or items that require modification or removal before final implementation.

To investigate the effect of sensory integration on gross motor function in children with Down syndrome. To investigate the effect of sensory integration on balance in children with Down syndrome.

This study attempts to learn more about the health of persons with Down syndrome after treatment for acute leukemia. Children with Down syndrome are at increased risk for side effects during treatment for acute leukemia, but it is unclear of their risk for long-term effects of cancer treatment. By learning more about the factors that may contribute to chronic health conditions and long-term effects after treatment for leukemia in persons with Down syndrome, clinical practice guidelines for survivorship care can be developed to help improve their quality-of-life.

The study investigators are interested in learning more about how drugs, that are given to children by their health care provider, act in the bodies of children and young adults in hopes to find the most safe and effective dose for children. The primary objective of this study is to evaluate the PK of understudied drugs currently being administered to children per SOC as prescribed by their treating provider.

This study will compare the effects of vestibular stimulation exercises and foot intrinsic muscle exercises on balance and functional mobility in children with Down syndrome aged 4-15 years. Children with Down syndrome commonly experience balance and mobility difficulties due to hypotonia, ligamentous laxity, and impaired postural control. The study will determine which of the two exercise approaches is more effective in improving balance and functional mobility, using the Pediatric Balance Scale (PBS) and Timed Up and Go (TUG) test. The findings may help physiotherapists select appropriate rehabilitation strategies to improve functional independence in children with Down syndrome.

The researchers are investigating if the Self-Supporting Nasopharyngeal Airway (ssNPA) device can be used in the treatment of obstructive sleep apnea in children with Hypotonic Upper Airway Obstruction (HUAO).

Down syndrome (DS) is associated with cognitive deficits, caused by alterations in neuroplasticity and synaptic transmission. Non-invasive brain stimulation techniques, such as transcranial direct current stimulation (tDCS), can modulate the brain's plasticity mechanisms and neurotransmitter balance. Anodal tDCS increases cortical excitability by depolarizing neurons, while cathodal tDCS decreases it through hyperpolarization. When combined with cognitive training, tDCS may produce faster and longer-lasting therapeutic effects. Although most of the neurorehabilitation studies have applied anodal excitatory stimulation, recent evidence suggests the potential cathodal inhibitory stimulation in neurodevelopmental disorders with alteration of synaptic transmission, as people with DS. Potentially both anodal and cathodal stimulation protocols could lead to positive clinical effects in DS. This proof-of-concept study is a double-blind, placebo-controlled, clinical trial aiming to evaluate the efficacy of two active tDCS protocols (anodal and cathodal) targeting the left inferior frontal gyrus (IFG) versus sham stimulation tDCS, combined with speech and language training, to improve language skills in adolescents and young adults with DS. The study also aims to identify the most effective parameters of tDCS treatment, for customization in adolescents and young adults with DS. Thirty-six participants, aged 12 to 21 years, will be randomly assigned to three groups receiving anodal, cathodal, or sham tDCS. Each participant will undergo 10 sessions of tDCS at 1 mA for 20 minutes, alongside speech and language training five times for two weeks. Neuropsychological, behavioral, biomarker (including brain-derived neurotrophic factor and neurofilament light chain), and electroencephalogram assessments will be performed at baseline, post-treatment, and three months after treatment completion. The study hypothesizes that tDCS will enhance language abilities, particularly expressive vocabulary, and modulate biomarkers of brain plasticity in DS participants. The study also hypothesizes that tDCS will enhance other cognitive and behavioral functions. Since tDCS effects may last, the study will check for improvements at the three-month. If effective, this combined approach of tDCS and language training could pave the way for new rehabilitation strategies for DS.

The emergence of crawling and walking is significantly delayed in infants with Down syndrome (DS), but the development of independent mobility provides infants with new opportunities for exploring the environment and interacting with objects and people that are important foundations for early learning. Increasing infant mobility early in development with body weight supported harness systems may support infant exploration, communication, and social interaction. This project will set the stage for the first clinical trial of a mobility-related intervention specifically tailored for infants with DS by testing the feasibility of harness systems with infants and families and identifying measures that will serve as primary outcome variables. Upon completion of this pilot project, necessary preliminary data and experience required for an in-home, high-impact clinical trial for infants with DS will have been obtained.

Background: Down syndrome is a genetic disorder that can cause heart defects and other problems in the body. People with Down syndrome are more likely to have infections, autoimmunity, and blood diseases. Some may need surgery to treat congenital heart problems. During this surgery, doctors sometimes remove part of the thymus. The thymus is an organ that plays a role in immune function. People who have had part of their thymus removed may get sick more often than others do. Objective: This natural history study will gather data about how removing part of the thymus affects the health of people with Down syndrome. Eligibility: People aged 1 year and older with Down syndrome. The study will include both people who have, and those who have not had, surgery to remove part of their thymus. Healthy relatives are also needed. Design: Participants with Down syndrome will have clinic visits at least once a year for 15 years. At each visit they will have a physical exam. They will give blood and stool samples. They will have tests of their heart and lung function. Participants aged 18 years or older may have at least 1 imaging scan: They will lie on a table that slides into a donut-shaped machine. The machine uses X-rays to take pictures of the inside of the body. Participants who have tissue samples collected from their bodies (biopsies) taken during the study may have extra tissue taken for research. Healthy relatives will also have visits once a year for 15 years. They will only have a physical exam and provide blood and stool samples.

Progressive age-related cognitive deficits occurring in both AD and DS have been connected to the degeneration of several neuronal populations, but mechanisms are not fully elucidated. The most consistent neuronal losses throughout the progression of AD are seen in cholinergic neurons where these losses negatively affect cognition, particularly in attention, learning, and memory formation. Evidence of reduced cholinergic integrity in DS is largely limited to animal models and post-mortem human data. The investigators propose to use molecular, functional, and structural biomarkers to assess the cholinergic integrity in adults with DS. The investigators anticipate using the data gathered in this pilot study to inform future study designs to determine AD risk stratification in DS by identifying individuals who show an accelerated decline in cholinergic integrity that correlates with cognitive and neurobehavioral changes. Also, our cholinergic biomarkers may identify whether individuals with DS are likely to respond to pro-cholinergic interventions, including the novel cholinergic modulators that are being developed to enhance cholinergic-sensitive cognitive functioning. The investigators anticipate using the data gathered here to inform future treatment studies in TRC-DS and beyond where novel cholinergic treatments may offer opportunities for early intervention in DS and be complementary to disease-modifying approaches such as anti-amyloid treatments.

The long-term study goal is to experimentally evaluate the components (and likely active ingredients) of early language interventions for young children with Down syndrome (DS). The overall objective is to determine how single-word and telegraphic simplification affects real-time language processing and word learning in young children with DS (relative to full, grammatical utterances). The proposed project will investigate three specific aims: 1) Determine how single-word and telegraphic simplification affects language processing. 2) Determine how single-word and telegraphic simplification affects word learning. 3) Evaluate child characteristics that may moderate the effects of linguistic simplification on language processing and word learning. Aim 1 will test the hypothesis that children with DS will process grammatical utterances faster and more accurately than telegraphic or single-word utterances. Aim 2 will test the hypothesis that overall, children will demonstrate better word learning in the grammatical compared to the single-word and telegraphic conditions. Aim 3 will test the hypothesis that receptive language and nonverbal cognitive abilities will be significant moderators, such that children with stronger linguistic and cognitive skills will show the greatest benefit from grammatical input but children with lower linguistic and cognitive scores will perform similarly across conditions.

This study evaluates the efficacy of transcranial direct current stimulation (tDCS) for depression with catatonia in individuals with Down syndrome (DS). 62 patients will be randomized to receive 15 sessions of active or sham tDCS. The primary objective is to measure changes in depressive/catatonic symptoms using the Bush-Francis Catatonia Rating Scale (BFCRS). Secondary objectives include safety, cognitive effects, EEG correlates, and biological markers (cortisol, BDNF, cytokines). The study aims to provide a non-pharmacological therapeutic alternative for this population

The goal of this clinical trial is to learn if pre-walking infants with Down syndrome can use a suspension walker in their home and community environments. The main questions it aims to answer are: * Is suspension walker intervention feasible for pre-walking infants with Down syndrome? * What are barriers to successfully using suspension walkers in home and community environments? * What are facilitators for successfully using suspension walkers in home and community environments? Participants will: * Use a suspension walker in the home and community for a three-month period (goal 20 minutes/day, 5 days/week) * Meet with a therapist three times in their home to learn how to use the walker * Track how often they use the walker for one week each month * Complete assessments of infants' gross motor skill and ability to use the walker before and after the three-month period * Be interviewed after the three-month period about their experiences using the walker

The Collaboration for Down Syndrome Progress (CDP) is a long-term study that follows people with Down syndrome of all ages. The goal is to better understand their health, development, and everyday experiences over time. Participants and their caregivers will answer questions, share medical information, and may give samples like blood or saliva. Some participants may also take part in optional activities such as sleep studies, movement tracking, or brain imaging. By collecting the same types of information at many sites, the CDP will help researchers learn why certain health conditions are more common in people with Down syndrome and how to improve care and quality of life.

The goal of this clinical trial is to learn if drumming lessons can increase self-control in children with Down syndrome. The main question it aims to answer is whether 2 months of drumming lessons can improve the behavioral control and timing skills in children with Down syndrome. Participants are between 7 and 15 years of age and receive two months of drumming lessons given by a professional drummer with extensive experience working with children with Down syndrome. Children in the experimental group visit our lab once before lessons start and once after lessons are completed. Children in the control group visit our lab twice before they start their lessons. Lab visits include brain recordings taken using a net-style cap, computer tasks, and drumming to music.