ABSTRACT
BACKGROUND: CUL3 encodes cullin-3, a core component of a ubiquitin E3 ligase. CUL3 mutations have recently been associated with autism spectrum disorder (ASD); however, the detailed clinical courses have been described in only a limited number of patients with CUL3 mutations and neurodevelopmental diseases, including ASD. CASE REPORT: A 21-month-old Japanese girl presented with febrile status epilepticus and thereafter exhibited developmental regression, including loss of her verbal ability, eye contact, and skills in activities of daily living. Trio-based exome sequencing identified a de novo two-base insertion in CUL3, c.1758_1759insTG, p.(Thr587*). CONCLUSION: We report a case of a patient with ASD and a stop-gain CUL3 variant. Screening of CUL3 variants is worth considering for patients with ASD, especially those with Rett-like developmental regression.