Autosomal dominant
Caused by a change in one copy of BCL11A that reduces its function. BCL11A regulates brain development and fetal haemoglobin, and its loss leads to persistently raised fetal haemoglobin. Most cases arise de novo.
Signs and symptoms
Developmental delay and intellectual disability of variable degree, with speech delay, low muscle tone and behavioural differences including autism. Microcephaly, squint and subtle facial features are common. Blood tests show raised fetal haemoglobin, which does not cause symptoms. Seizures occur in some people, and brain scans may show hindbrain differences such as a small brainstem.
What a diagnosis changes
Developmental, speech and educational support, with eye and behavioural assessment and seizure treatment if needed. Most cases arise de novo, but genetic counselling and parental testing guide recurrence risk.
Genes analysed
Also known as
BCL11A-related BAFopathy; BCL11A-related intellectual developmental disorder with persistence of fetal hemoglobin; BCL11A-related intellectual developmental disorder with persistence of foetal haemoglobin; Dias-Logan syndrome; DILOS; DILOS; hereditary persistence of fetal hemoglobin-intellectual disability syndrome; intellectual developmental disorder with hereditary persistence of foetal Haemoglobin; intellectual developmental disorder with persistence of foetal Haemoglobin; intellectual developmental disorder with persistence of foetal HEMOGLOBIN
