Classic Ehlers-Danlos Syndrome in a Son and Father with a Heart Transplant Performed in the Father

Spectrum of Rare and Common Genetic Variants in Arrhythmogenic Cardiomyopathy Patients

Arrhythmogenic cardiomyopathy (ACM) is a rare inherited disorder, whose genetic cause is elusive in about 50–70% of cases. ACM presents a variable disease course which could be influenced by genetics. We performed next-generation sequencing on a panel of 174 genes associated with inherited cardiovascular diseases on 82 ACM probands (i) to describe and classify the pathogenicity of rare variants according to the American College of Medical Genetics and Genomics both for ACM-associated genes and for genes linked to other cardiovascular genetic conditions; (ii) to assess, for the first time, the impact of common variants on the ACM clinical disease severity by genotype-phenotype correlation and survival analysis. We identified 15 (likely) pathogenic variants and 66 variants of uncertain significance in ACM-genes and 4 high-impact variants in genes never associated with ACM (ABCC9, APOB, DPP6, MIB1), which deserve future consideration. In addition, we found 69 significant genotype-phenotype associations between common variants and clinical parameters. Arrhythmia-associated polymorphisms resulted in an increased risk of arrhythmic events during patients’ follow-up. The description of the genetic framework of our population and the observed genotype-phenotype correlation constitutes the starting point to address the current lack of knowledge in the genetics of ACM.

Classic Ehlers-Danlos syndrome and cardiac transplantation - Is there a connection?

Ehlers-Danlos syndrome (EDS) is a heterogeneous group of connective tissue disorders comprised of several types. Classic EDS is an autosomal dominant disorder with stretchable skin, delayed wound healing with poor scarring, joint hypermobility with subluxations or dislocations, easy bruisability, hernias, aneurysms and cardiac abnormalities. Advances in genomics technology using next-generation sequencing has led to the discovery of causative genes for connective tissue disorders, hereditary cardiomyopathies and cardiovascular diseases including several genes for connective tissue disorders. A 55 year-old male exhibited thin stretchable skin, atrophic scars, easy bruising, joint pain and dislocations requiring multiple knee surgeries and a Beighton hyperflexibility score of 6 out of 7. He was found to have a heterozygous missense COL5A1 gene variant involving exon 3 at nucleotide c:305T>A with an amino acid position change at p.lle102Asn consistent with classic EDS. He had a heart transplant at 43 years of age due to cardiac failure of unknown cause. This patient with classic EDS is brought to medical attention and should be of interest to cardiologists, heart transplant specialists and surgeons, particularly in individuals with unexplained cardiac failure and then diagnosed prior to surgical intervention to avoid poor wound healing, scarring and other tissue involvement (e.g., vascular anomalies, blood pressure instability, aneurysms) as components of EDS.

Ehlers-Danlos syndrome and other heritable connective tissue disorders that impact pregnancies can be detected using next-generation DNA sequencing

Ehlers-Danlos syndromes (EDS) are a genetically heterogeneous group of inherited connective tissue disorders classified into six major types with a variable collection of findings and different inheritance patterns. Although complications occur in about one-half of pregnancies in women with EDS, the majority can have a good outcome if managed appropriately. Classic EDS is characterized by joint hypermobility, loose skin with poor healing and easy bruising, musculoskeletal problems with chronic pain and at risk for pre-term delivery. In addition, the vascular form of EDS can have cardiac anomalies, aneurysms, gastrointestinal perforation and uterine rupture during pregnancy. Due to overlapping features among the connective tissue disorders, it is difficult to categorize the disorder into specific types without detailed genetic testing which is now available through advanced genomic technology using next-generation DNA sequencing, searching genomic databases and bioinformatics approach. Therefore, obstetrical complications are variable but relate to specific connective tissue disorders requiring an exact diagnosis. There are several dozen genes causing connective tissue disorders that are currently available for testing using next-generation sequencing and bioinformatics to provide pertinent care, treatment and surveillance of the affected pregnant woman but also for her at-risk fetus related to the specific heritable condition.