[Clinical phenotype and genetic analysis of a case of 5q14.3 microdeletion syndrome]

To explore the clinical features and genetic characteristics of a child with 5q14.3 microdeletion syndrome.

Whole exome sequencing (WES) and low-coverage massively parallel copy number variation sequencing (CNV-seq) were used to determine the potentially pathogenic variants as well as the copy number variations (CNVs). Candidate CNVs were verified by real-time fluorescence quantitative PCR.

The patient presented with psychomotor retardation, epilepsy, peculiar face and hypotonia. The results of WES suggested that he has carried a heterozygous deletion for chr5:86 564 268-88 119 605. CNV-seq indicated that the patient carried a heterozygous deletion of 4.76 Mb heterozygous deletion on chromosome 5q14.3. The MEF2C gene and RASA1 gene in the deletion area were verified by real-time fluorescence quantitative PCR. The results showed that the MEF2C geneand RASA1 gene were heterozygous deletion, which was consistent with the sequencing results.

The child was diagnosed with 5q14.3 microdeletion syndrome. Haploinsufficiency of the MEF2C gene may underlie the manifestations of 5q14.3 microdeletion syndrome.