(A) Probands with the TNNT2 c.571-1G>A (rs483352835) splice-site variant by self-reported ancestry and disease phenotype. (Bi) NCBI RefSeq transcripts for the TNNT2 gene. Exons are numbered as per NM_001001430.3. (Bii) SpliceAI predicts weakening of the canonical acceptor splice site in Exon 12 and strengthening of a cryptic acceptor splice site three nucleotides downstream, resulting in deletion of Gln191. There is no significant change in SpliceAI score for the Exon 12 canonical donor splice site. (Biii) The cryptic acceptor is the annotated acceptor splice site for NM_001001432.3. (C) Frequency of variant TNNT2; NM_001001430.2: c.571-1G>A (rs483352835) in genomic reference databases. (D) Geographical Map of Oceania (Polynesia, Micronesia, and Melanesia) with population-specific TNNT2 c.571-1G>A (rs483352835) allele frequencies. This work is licensed under Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0). The original can be found at: https://commons.wikimedia.org/wiki/File:Oceania_UN_Geoscheme_-_Map_with_Zones.svg#/media/File:Oceania_UN_Geoscheme_Regions. HCM, hypertrophic cardiomyopathy; DCM, dilated cardiomyopathy; RCM, restrictive cardiomyopathy; SUD, sudden unexplained death; Fhx, family history; SCD, sudden cardiac death