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1.Morita H, Rehm HL, Menesses A, McDonough B, Roberts AE, Kucherlapati R, Towbin JA, Seidman JG, Seidman CE. Shared genetic causes of cardiac hypertrophy in children and adults. N Engl J Med . 2008;358:1899–1908. PMID: 18403758. ### Study Hypothesis Mutations in sarcomere proteins that are implicated in adult forms of hypertrophic cardiomyopathy may play a role in idiopathic cardiac hypertrophy with onset in childhood, a disorder associated with poor prognosis. ### How Was the Hypothesis Tested? Morita and colleagues1 screened for mutations in 8 genes encoding sarcomeric proteins (MYH7, MYBPC3, TNNT2, TNNI3, TPM1, MYL3, MYL2, and ACTC) using direct sequencing techniques in 84 children with idiopathic cardiac hypertrophy. Mutations in these genes cause adult-onset cardiomyopathy. ### Principal Findings The authors identified mutations in almost half of children without a positive family history of cardiomyopathy (25 of 51 affected children) and in two thirds (21 of 33) of affected children with familial cardiomyopathy. Mutations in MYH7 (encoding β-myosin heavy chain) and MYBPC3 (encoding myosin-binding protein C) were the most frequent variants identified in the children. In the subgroup with sporadic (nonfamilial) cardiac hypertrophy, boys were more likely than girls to harbor mutations. ### Implications The authors conclude that childhood onset of cardiac hypertrophy should provoke genetic investigation and family assessment because about 50% of cases in this series were attributable to mutations routinely screened for in adults with unexplained cardiac hypertrophy. Identification of such mutations in children with cardiac hypertrophy would raise the possibility that management strategies used for adults with genetic cardiac hypertrophy may improve clinical outcomes in these children. 2.Lynch AI, Boerwinkle E, Davis BR, Ford CE, Eckfeldt JH, Leiendecker-Foster C, Arnett DK. Pharmacogenetic association of the NPPA T2238C genetic variant with cardiovascular disease outcomes in patients with hypertension. JAMA . 2008;299:296–307. PMID: 18212314. ### Study Hypothesis Variation in NPPA gene, which encodes the precursor of atrial natriuretic peptide, may influence the efficacy of different …