Chapter 5: Genetics of Dilated Cardiomyopathy: Current Knowledge and Future Perspectives

Nowadays, a huge claim for personalized medicine is progressively growing, and, along this way, genetic studies represent one of the most representative steps. Dilated cardiomyopathy (DCM) can be the consequence of clearly defined external etiologic factors, such as viral infections, toxins, drugs, metabolic disorders, etc., but at least 30–40% of cases (and maybe more) have a prevalent genetic origin, and in the remaining part, genetics may still play an important role. With the expansion of clinical genetic testing, using high-quality next-generation sequencing (NGS) extended panels, these genetic causes of DCM have been increasingly identified. More than 50 genes, mapping to multiple biological pathways, are currently considered disease related, and causative variants can be identified in up to 35% of cases. This growing amount of genetic informations, however, is still not followed by a parallel advance toward tailored clinical management. The reasons behind this gap are currently under investigation in the scientific community: the aim of this chapter is to provide a guide through the complexity of the genotype-phenotype interaction, analyzing (1) the most frequently encountered genes in DCM, (2) technical issues in NGS, (3) controversies beyond sequencing data interpretation, (4) the contribution of environmental modifiers, and (5) evidence-based genotype-phenotype correlations in DCM.