The pathogenicity of genetic variants previously associated with left ventricular non-compaction.

Background: Left ventricular non-compaction (LVNC) is a rare cardiomyopathy. Many genetic variants have been associated with LVNC. However, the number of the previous LVNC-associated variants that are common in the background population remains unknown. The aim of this study was to provide an updated list of previously reported LVNC-associated variants with biologic description and investigate the prevalence of LVNC variants in healthy general population to find false-positive LVNC-associated variants.

Methods And Results: The Human Gene Mutation Database and PubMed were systematically searched to identify all previously reported LVNC-associated variants. Thereafter, the Exome Sequencing Project (ESP) and the Exome Aggregation Consortium (ExAC), that both represent the background population, was searched for all variants. Four in silico prediction tools were assessed to determine the functional effects of these variants. The prediction results of those identified in the ESP and ExAC and those not identified in the ESP and ExAC were compared. In 12 genes, 60 LVNC-associated missense/nonsense variants were identified. MYH7 was the predominant gene, encompassing 24 of the 60 LVNC-associated variants. The ESP only harbored nine and ExAC harbored 18 of the 60 LVNC-associated variants. In total, eight out of nine ESP-positive variants overlapped with the 18 variants identified in ExAC database.

Conclusions: In this article, we identified 9 ESP-positive and 18 ExAC-positive variants of 60 previously reported LVNC-associated variants, suggesting that these variants are not necessarily the monogenic cause of LVNC.