*3.1. Molecular Findings in the Study Cohort*

We identified 18 different *LMNA* variants (three identified twice) in 21 probands (Table 1). Of the 18 variants, 14 were described before [13–15,18,20–28] and four were novel. The identified variants were pathogenic (*n* = 12) or likely pathogenic (*n* = 6) according to ACMG criteria. Figure 1 shows the distribution of *LMNA* variants found in this study in the topology of the *LMNA* gene. Eight (38.1%) of 21 probands carried *LMNA* missense variants. Of the 13 probands with non-missense variants, seven had nonsense variants, four had frameshift variants, one had a large deletion, and one was splice variant. Non-missense variants were expected to result in truncation of the protein or, in one case (c.640-10A>G), in aberrant splicing resulting in a three amino acid insertion [29]. In five probands which had NGS performed, no additional likely pathogenic/pathogenic rare variants according to ACMG criteria in coding/splicing regions of genes causing DCM were found.

**Figure 1.** Distribution of *LMNA* variants in our study cohort. Legend: NLS, nuclear localization signal.


 **1.** Genotyping results and clinical phenotypes in probands.

**Table**

localization signal; nsVT:

non-sustained

 ventricular tachycardia; SCA: sudden cardiac arrest; sVT: sustained ventricular tachycardia.
