Novel variants in the ACTA2 and MYH11 genes in a Cypriot family with thoracic aortic aneurysms: a case report.

Background: Thoracic aortic aneurysm (TAA) and/or thoracic aortic aneurysm and dissection (TAAD) is characterized by a considerable risk of morbidity and mortality of affected individuals. It is inherited in an autosomal dominant pattern and the 20% of patients with non-syndromic TAA have a positive family history. To date, the genetic basis of Cypriot patients with TAA has not been investigated. The purpose of this case report is to determine underlying genetic cause in this Cypriot family with TAA.

Case Presentation: In this report we present a patient with hyper-acute onset chest and back pain diagnosed with Type A Aortic Dissection with severe aortic valve regurgitation, who underwent emergency aortic surgery and Bentall procedure. Further investigation of the patient's family was undertaken where both parents and an additional child were also found to be affected. A targeted sequencing panel including genes with known association to TAA was used to identify causative mutations in the index patient. Massively Parallel Sequencing results identified a frameshift deletion c.363_367del GAGTC, p.Met121Ilefs*5 in the ACTA2 gene and a non-synonymous variant c.3234C > G, p.Ile1078Met in the MYH11 gene. The presence or absence of these variants in the index patient and other family members was verified by Sanger sequencing. To our knowledge, this is the first report of a Cypriot family case diagnosed with TAA presented by two novel variants one in the ACTA2 and the other in the MYH11 genes.

Conclusions: We describe two novel variants in a Cypriot family with TAA that are potentially pathogenic, highlighting the importance of molecular genetic evaluation in families with TAA. These results may prove useful for screening purposes in Cypriot patients with non-syndromic familial TAA facilitating early identification of atrisk family members and direct intervention.