Abstract: Objective To improve the understanding of clinical phenotype and genotype of pachygyria with subcortical band heterotopia. Method The clinical data and genetic test results of a boy with pachygyria with subcortical band heterotopia were retrospectively analyzed. Results A boy aged 1 -month- 25 -day was admitted to the hospital for 1 week due to poorly playful response. Clinical features included soft anterior fontanelle, slightly hypertonia in lower limbs, and head circumference was 38 cm. The neuropsychological development test for 0 - 6 years showed a low developmental quotient. Head MRI revealed pachygyria with subcortical band heterotopia in bilateral frontal parietal lobe. Next generation sequencing revealed a c.829 C>T hemizygous variation in DCX gene, which was inherited from his mother. This pathogenic mutation of DCX gene has been reported in the literature. Conclusion The mutation found in this patient was the first report in China, which expanded local mutation spectrum of DCX.

Key words: band heterotopia; pachygyria; DCX gene; hemizygous variation