[Genetic analysis of a child with global developmental delay and neurofibromatosis type 1].

To explore the genetic basis for a child with global developmental delay and neurofibromatosis type 1 (NF1).The patient underwent clinical examination. Whole exome sequencing (WES) was carried out to detect pathogenic genetic variants.The child had cafe au lait spots all over her body, pigmentation in the back, and global developmental delay as assessed by Gese II. Cranial MRI revealed globular abnormal density in the lower hemisphere of left posterior cranial fossa. WES detected a novel variant of the NF1 gene, c.6513-6515del (p.Tyr2171), which was strongly correlated with her clinical phenotype. The same variant was not found in either parent and was unreported previously.The c.3842T>G variant of the NF1 gene probably underlay the NF1 and global developmental delay in this child, for whom prompt symptomatic treatment and regular follow-up were recommended.