Objective: To detect potential mutation of MLC1 gene in a child affected with megalencephalic leukoencephalopathy with subcortical cysts (MLC).
Methods: Clinical symptoms of the patient were retrieved. Peripheral blood DNA samples from the patient, her parents and healthy controls were collected. Potential mutation of the MLC1 gene was detected by polymerase chain reaction and Sanger sequencing.
Results: The patient presented with severe motor developmental delay and a giant skull. Magnetic resonance scan showed diffuse white matter swelling in bilateral hemispheres. DNA sequencing identified a novel homozygous c.177-c.180delC mutation of the MLC1 gene. The parents of the patient both carried a heterozygous mutation c.177-c.180delC but had a normal phenotype.
Conclusion: A novel MLC1 mutation c.177-c.180delC has been identified in a patient with MLC. The mutation is presumably disease-causing and has derived from parents who are both carriers.