Hypertension and Brachydactyly Syndrome Associated With Vertebral Artery Malformation Caused by a PDE3A Missense Mutation

BACKGROUND

Hypertension and brachydactyly syndrome (HTNB), also called Bilginturan syndrome, is a rare autosomal dominant disorder characterized by severe salt-independent hypertension, a short stature, brachydactyly, and death from stroke before the age of 50 years when untreated. The purpose of the present study was to identify a PDE3A mutation leading to HTNB associated with vertebral artery malformation in a Chinese family.

METHODS

Peripheral blood samples were collected from all subjects for DNA extraction. Next-generation sequencing and Sanger sequencing were performed to identify the PDE3A mutation. A comparative overview was performed in the probands with HTNB caused by PDE3A mutations.

RESULTS

Genetic analysis identified a missense mutation in PDE3A, c.1346G>A, in the proband with HTNB. This mutation, resulting in p.Gly449Asp, was located in a highly conserved domain and predicted to be damaging by different bioinformatics tools. Cosegregation analyses showed that the proband inherited the identified mutation from her father. Antihypertensive therapy was effective for the proband. Comparative overview of HTNB probands with 9 different PDE3A mutations revealed phenotypic heterogeneity.

CONCLUSIONS

Genetic screening can significantly improve the diagnosis of HTNB patients at an early age. Our study not only adds to the spectrum of PDE3A mutations in the Chinese population and extends the phenotype of HTNB patients to include vertebral malformation but also improves the awareness of pathogenesis in HTNB patients. We emphasize the importance of antihypertensive treatment and long-term follow-up to prevent stroke and adverse cardiovascular events.