2q37 deletion syndrome is a rare genetic condition characterized by the absence of a small segment of genetic material. It presents with a broad spectrum of physical, developmental, and behavioral features. The manifestation and severity of these characteristics vary significantly among affected individuals.
Genetic Basis of 2q37 Deletion Syndrome
The cause of 2q37 deletion syndrome is a missing piece of genetic information located on chromosome 2. Specifically, the deletion occurs on the long arm, ‘q’, at band 37. Chromosomes are structures within cells that carry genes, which contain instructions for how bodies grow and function. Humans typically have 46 chromosomes arranged in 23 pairs.
The size and exact position of the deleted segment on chromosome 2q37 can differ, contributing to the wide range of observed symptoms and their severity. Most cases arise as a “de novo” mutation, meaning the deletion is new in the affected individual and not inherited. In rare instances, a parent may carry a chromosomal rearrangement that can be passed down, resulting in the deletion in their child.
Common Characteristics and Features
Individuals with 2q37 deletion syndrome often present with a range of features.
Physical Features
These can include distinctive facial characteristics such as a prominent forehead, sparse or highly arched eyebrows, deep-set eyes, and full cheeks. Dental anomalies may also be present. Skeletal abnormalities are commonly observed, with brachydactyly type E (unusually short fingers and toes) affecting about half of individuals, often with a shortened fourth toe that may overlap others. Short stature and joint hypermobility are also reported.
Developmental and Cognitive Impacts
Most affected individuals experience global developmental delays and intellectual disability, which can range from mild to severe. Speech and language delays are very common, affecting about 45% of individuals. These delays can significantly impact communication and learning skills.
Behavioral and Neurological Aspects
Features of autism spectrum disorder are present in approximately 25% of individuals, characterized by repetitive behaviors, odd obsessions, and impaired social interaction. Attention deficit hyperactivity disorder (ADHD) and sleep disturbances are also reported. Seizures occur in 20% to 35% of patients.
Other Medical Concerns
Gastrointestinal issues, congenital heart defects, and kidney abnormalities are sometimes observed. A rare form of kidney cancer called Wilms tumor has also been reported in a few individuals with 2q37 deletion syndrome.
Diagnosis and Identification
Diagnosis of 2q37 deletion syndrome begins with clinical suspicion based on a child’s observable features and developmental milestones. Characteristic physical traits, such as specific facial features and skeletal anomalies, along with developmental delays, can prompt healthcare providers to consider a genetic cause.
Confirmation relies on specific genetic testing methods. Chromosomal microarray (CMA) is a primary test, detecting small missing or extra pieces of chromosomes not visible with traditional karyotyping. Fluorescent in situ hybridization (FISH) is another technique that can confirm a deletion at the 2q37 band. These tests analyze genetic material to pinpoint the exact deletion on chromosome 2.
Genetic testing is essential for a definitive diagnosis, as some other conditions may present with similar symptoms. The detailed genetic information helps differentiate 2q37 deletion syndrome from other disorders with overlapping clinical features. This precise identification is important for understanding the prognosis and guiding management strategies.
Supportive Care and Therapies
Management of 2q37 deletion syndrome involves a multidisciplinary approach focused on supportive care and various therapies tailored to an individual’s specific needs. Early intervention programs are beneficial, providing access to therapies to maximize developmental outcomes.
Developmental Therapies
These therapies play a significant role in addressing specific challenges. Physical therapy helps improve motor skills and muscle tone. Occupational therapy focuses on developing daily living activities and fine motor skills. Speech and language therapy is also widely used to support communication development, given the common delays in this area.
Educational and Medical Support
Educational support is customized through individualized education programs (IEPs) and special education services, ensuring that children receive appropriate learning accommodations. Medical management addresses any specific health issues, such as cardiac, gastrointestinal, or neurological concerns, often requiring consultation with various specialists. Seizures, if present, are typically managed with medication.
Behavioral Interventions and Support
Behavioral interventions, including strategies like Applied Behavior Analysis (ABA), may be employed to help manage behavioral challenges, such as those associated with autism spectrum disorder features. Connecting with family support groups and resources offers emotional support, shared experiences, and practical advice for families. The overall goal of these comprehensive interventions is to enhance the individual’s quality of life and help them reach their fullest potential.