A UK Biobank genome-wide association study identified distinct genetic loci across three rare but deadly cardiovascular conditions: Brugada syndrome showed concentrated signals at THSD7B and TRPC4; takotsubo cardiomyopathy implicated ANKRD31 and PREX1; primary pulmonary arterial hypertension pointed to ANO10 and SHF. Proteomic Mendelian randomization using pQTLs further flagged lipoprotein(a) — encoded by LPA — as a candidate causal protein for takotsubo cardiomyopathy, while several takotsubo variants mapped to unannotated non-coding regions.
These findings matter because all three conditions carry significant mortality yet have attracted a fraction of the genomic investment lavished on common cardiovascular diseases like coronary artery disease. Identifying TRPC4 — a transient receptor potential cation channel — in Brugada syndrome is biologically intriguing given established links between TRP channels and cardiac arrhythmia. The LPA signal in takotsubo is notable: elevated lipoprotein(a) is already an emerging therapeutic target in atherosclerosis, and this preliminary causal link opens a plausible mechanistic bridge worth investigating. That said, UK Biobank case counts for rare diseases are inherently small, limiting statistical power and increasing false-positive risk. The Mendelian randomization results for circulating proteins were described as limited, tempering enthusiasm. Non-coding variant signals also remain functionally uncharacterized. Critically, this is a preprint posted on medRxiv and has not yet undergone peer review — findings and conclusions may change substantially before publication. Consider this hypothesis-generating, not practice-changing.