[Genetic analysis and prenatal diagnosis of a Chinese pedigree affected with Usher syndrome due to novel compound heterozygous variants of PCDH15 gene].

OBJECTIVE

To analyze the clinical features and genetic variant in a patient with Usher syndrome.

METHODS

Whole exome sequencing was carried out for the patient. Suspected variants were validated by Sanger sequencing of her parents and fetus.

RESULTS

The proband was found to harbor compound heterozygous variants c.17_18insA (p.Tyr6Ter*) and c.4095_4096insA (p.Arg1366Lys fs*38) of the PCDH15 gene (NM_033056), which were respectively inherited from her father and mother. The same variants were not detected in 100 healthy controls. Based on the guidelines of the American Society of Medical Genetics and Genomics, both variants were predicted to be pathogenic (PVS1+PM2+PP4). By prenatal diagnosis, her fetus was found to carry the c.4095_4096insA variant. After birth, the child has passed neonatal hearing screening test, and no abnormal auditory and visual function was found after the first year.

CONCLUSION

The compound heterozygous variants c.17_18insA (p.Tyr6Ter*) and c.4095_4096insA (p.Arg1366Lys fs*38) of the PCDH15 gene probably underlay the Usher syndrome is this proband.