A case of megalencephalic leukoencephalopathy with subcortical cysts type 1 was identified with a novel compound heterozygous alteration (c.135delC; c.423+2dupT) in China.

Key Clinical Message We report a compound heterozygous mutation (c.135delC; c.423+2dupT) of MLC1 gene in a Chinese patient underlying infantile macrocephaly and neurological deterioration in early childhood. Brain MRI revealed diffusion abnormality in swollen white matter and a subcortical cyst. The cDNA sequencing analysis for the c.423+2dupT variant revealed skipping of exon 5. [ABSTRACT FROM AUTHOR]