Letter to the editor regarding the article “A case of hypertrophic and dilated cardiomyopathic sudden cardiac death: De novo mutation in TTN and SGCD genes”

We recently read the article entitled “A case of hypertrophic and dilated cardiomyopathic sudden cardiac death: de novo mutation in TTN and SGCD genes” by Baydar et al. (1) published in the Anatolia Journal of Cardiology in late 2016 with great interest. We commend the authors for their contribution to improving our understanding of sudden cardiac death mechanisms and suggesting potential reasons for occurrence of the condition of genetic origin. We do, however, have a number of thoughts about the study, which are outlined below. The authors mentioned de novo mutation in the sarcoglycan (SGCD) and titin (TTN) genes. The article fails to mention, however, the parent-based variant approach to analysis. In human genetic diseases, the term “de novo mutation” by definition refers to an alteration in a gene that is present for the first time in one family member as a result of a mutation in a germ cell of one of the parents or in the zygote itself. It is only by analyzing the parents that their true contribution to the disease burden can be proven.