1p36 deletion syndrome

1p36 deletion syndrome (also known as monosomy 1p36 or 1p36 microdeletion syndrome) is a chromosomal disorder caused by a deletion of genetic material from the short arm (p) of chromosome 1 at band 36. It is one of the most common terminal deletion syndromes in humans. The condition affects multiple body systems and is characterized by distinctive facial features, including a flat nasal bridge, deep-set eyes, straight eyebrows, a pointed chin, and a large or late-closing anterior fontanelle. Individuals typically present with intellectual disability of varying severity, developmental delay, hypotonia (low muscle tone), and seizures, which occur in approximately half of affected individuals. The syndrome affects the neurological, cardiovascular, musculoskeletal, and sensory systems. Structural brain abnormalities may be present, and many individuals have speech and language impairment that is often more severe than their overall cognitive delay. Congenital heart defects, including cardiomyopathy (particularly dilated cardiomyopathy), patent ductus arteriosus, and other structural heart anomalies, are reported in a significant proportion of patients. Hearing loss (sensorineural or conductive) and vision problems are also common. Behavioral features may include self-injurious behavior, temper outbursts, and autistic-like features. Growth abnormalities, feeding difficulties in infancy, and short stature may also be observed. There is currently no cure for 1p36 deletion syndrome, and management is supportive and symptom-based. Treatment typically involves early intervention programs, physical therapy, occupational therapy, and speech therapy to optimize developmental outcomes. Seizures are managed with antiepileptic medications, and cardiac anomalies may require medical or surgical intervention. Regular monitoring by a multidisciplinary team including neurologists, cardiologists, audiologists, and ophthalmologists is recommended. Genetic counseling is advised for affected families to discuss recurrence risk and family planning.

Common questions about 1p36 deletion syndrome