The first Chinese intellectual developmental disorder, autosomal recessive 57 patient with two novel MBOAT7 variants

Background: Intellectual disability (ID) is a con neurodevelopmental disorder in children. The genetic etiology of ID is complex, but more subtypes are defined due to the broad application of next-generation sequencing.

Methods: Whole-exome sequencing (WES) and Sanger sequencing was applied in a family with ID.

Results: We report a Chinese 7.5-year-old boy, born to non-consanguineous parents. He showed severe intellectual disability, seizures and autistic features. Two previously unreported variants in MBOAT7, c.669C>G (p.(Tyr223*)) and c.1095C>G (p.(Ser365Arg)) were identified by trio-WES. His mother is a heterozygous carrier of the c.1095C>G variant. The c.669C>G variant is a de novo variant which was undetected in his parents. By construction of the full-length cDNA of the patient's MBOAT7, we verified that these two variants were trans-compound heterozygous variants, which support the genetic etiology of this patient.

Conclusion: This patient is the first Chinese case of intellectual developmental disorder (IDD), autosomal recessive 57 (OMIM:617188) with two unreported MBOAT7 variants.