[Analysis of ACADVL gene variant in a Chinese pedigree affected with Very-long-chain acl-CoA dehydrogenase deficiency].

Objective: To carry out genetic testing on a child diagnosed with Very-long-chain acyl-CoA dehydrogenase deficiency (VLADD) in order to provide a basis for genetic counseling and prenatal diagnosis for his family.

Methods: Whole exome sequencing was performed for the proband. Candidate variant sites in the ACADVL gene were verified by Sanger sequencing, and their pathogenicity was predicted based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). Prenatal diagnosis was performed on the fetus upon subsequent pregnancy. This study was approved by the Luoyang Maternal and Child Health Care Hospital (Ethics No. ).

Results: The proband was found to harbor compound heterozygous variants of the ACADVL gene, namely c.1532G>A and 1827+2_1827+12del, which were inherited from his mother and father, and classified as likely pathogenic and pathogenic, respectively. By combining the clinical manifestations of the proband and the results of blood tandem mass spectrometry and genetic testing, the child was ultimately diagnosed as cardiomyopathy type VLADD. Prenatal diagnosis showed that the fetus has carried the same compound heterozygous variants, and the couple had opted to terminate the pregnancy.

Conclusion: The c.1532G>A/1827+2_1827+12del compound heterozygous variants of the ACADVL gene probably underlay the pathogenesis of VLADD in this pedigree. The discovery of the 1827+2_1827+12del variant has enriched the mutational spectrum of the ACADVL gene.