Circulation: Cardiovascular Genetics最新文献

There have been major advances in our knowledge of the contribution of DNA sequence variations to cardiovascular disease and stroke. However, the inner workings of the body reflect the complex interplay of factors beyond the DNA sequence, including epigenetic modifications, RNA transcripts, proteins, and metabolites, which together can be considered the "expressed genome." The emergence of high-throughput technologies, including epigenomics, transcriptomics, proteomics, and metabolomics, is now making it possible to address the contributions of the expressed genome to cardiovascular disorders. This statement describes how the expressed genome can currently and, in the future, potentially be used to diagnose diseases and to predict who will develop diseases such as coronary artery disease, stroke, heart failure, and arrhythmias.

Background: PCSK9 loss-of-function (LOF) variants allow for the examination of the effects of lifetime reduced low-density lipoprotein cholesterol (LDL-C) on cardiovascular events. We examined the association of PCSK9 LOF variants with LDL-C and incident coronary heart disease and stroke through a meta-analysis of data from 8 observational cohorts and 1 randomized trial of statin therapy.

Methods and results: These 9 studies together included 17 459 blacks with 403 (2.3%) having at least 1 Y142X or C679X variant and 31 306 whites with 955 (3.1%) having at least 1 R46L variant. Unadjusted odds ratios for associations between PCSK9 LOF variants and incident coronary heart disease (851 events in blacks and 2662 events in whites) and stroke (523 events in blacks and 1660 events in whites) were calculated using pooled Mantel-Haenszel estimates with continuity correction factors. Pooling results across studies using fixed-effects inverse-variance-weighted models, PCSK9 LOF variants were associated with 35 mg/dL (95% confidence interval [CI], 32-39) lower LDL-C in blacks and 13 mg/dL (95% CI, 11-16) lower LDL-C in whites. PCSK9 LOF variants were associated with a pooled odds ratio for coronary heart disease of 0.51 (95% CI, 0.28-0.92) in blacks and 0.82 (95% CI, 0.63-1.06) in whites. PCSK9 LOF variants were not associated with incident stroke (odds ratio, 0.84; 95% CI, 0.48-1.47 in blacks and odds ratio, 1.06; 95% CI, 0.80-1.41 in whites).

Conclusions: PCSK9 LOF variants were associated with lower LDL-C and coronary heart disease incidence. PCSK9 LOF variants were not associated with stroke risk.

Background: Atherosclerotic plaque rupture is accompanied by an acute decrease in the carotid plaque expression of micro-RNAs (miRs)-221 and miR-222. Circular RNA (circR)-284 is a potential inhibitor of miR-221/miR-222 activity. We aimed to determine whether changes in the serum levels of these noncoding RNAs are observed in patients with asymptomatic high-grade carotid disease versus patients with acutely symptomatic carotid disease and recent ischemic stroke. Additionally, we tested the use of functionally related noncoding RNA pairs to enhance the discriminatory power of noncoding RNAs as circulating biomarkers.

Methods and results: Serum levels of miR-221, miR-222, miR-145, and circR-284 were measured in 24 asymptomatic (asymptomatic) and 17 acutely symptomatic patients ([urgent] ischemic cerebrovascular event within the previous 5 days) undergoing carotid endarterectomy. miR-221 was significantly lower, whereas circR-284 was elevated in the serum of the urgent compared with the asymptomatic group. The ratio of serum circR-284:miR-221 was significantly elevated in the urgent group (P=0.0002) and exhibited favorable characteristics as a biomarker indicative of carotid plaque rupture and stroke. A validation study in 112 patients (47 asymptomatic, 41 urgent, and 24 patients with a cerebrovascular event between 5 and 180 days of the carotid endarterectomy [symptomatic]) confirmed elevation of serum circR-284:miR-221 uniquely in the urgent group (P<0.001) and favorable sensitivity and specificity for detecting plaque rupture and stroke.

Conclusions: Serum circR-284:miR-221 has potential as a diagnostic biomarker of carotid plaque rupture and stroke. Moreover, we demonstrate the use of functionally related pairs of circulating noncoding RNAs as biomarkers in cardiovascular disease.

Background: Left ventricular noncompaction (LVNC) is a genetically and phenotypically heterogeneous disease and, although increasingly recognized in clinical practice, there is a lack of widely accepted diagnostic criteria. We sought to identify novel genetic causes of LVNC and describe genotype-phenotype correlations.

Methods and results: A total of 190 patients from 174 families with left ventricular hypertrabeculation (LVHT) or LVNC were referred for cardiac magnetic resonance and whole-exome sequencing. A total of 425 control individuals were included to identify variants of interest (VOIs). We found an excess of 138 VOIs in 102 (59%) unrelated patients in 54 previously identified LVNC or other known cardiomyopathy genes. VOIs were found in 68 of 90 probands with LVNC and 34 of 84 probands with LVHT (76% and 40%, respectively; P<0.001). We identified 0, 1, and ≥2 VOIs in 72, 74, and 28 probands, respectively. We found increasing number of VOIs in a patient strongly correlated with several markers of disease severity, including ratio of noncompacted to compacted myocardium (P<0.001) and left ventricular ejection fraction (P=0.01). The presence of sarcomeric gene mutations was associated with increased occurrence of late gadolinium enhancement (P=0.004).

Conclusions: LVHT and LVNC likely represent a continuum of genotypic disease with differences in severity and variable phenotype explained, in part, by the number of VOIs and whether mutations are present in sarcomeric or nonsarcomeric genes. Presence of VOIs is common in patients with LVHT. Our findings expand the current clinical and genetic diagnostic approaches for patients with LVHT and LVNC.