尿调节素及UMOD基因与慢性肾病的相关性研究进展

尿调节素,又称Tamm-Horsfal蛋白,是由肾小管髓袢升支粗段的小管上皮细胞分泌、也是正常人尿液中含量最多的蛋白。研究发现尿调节素具有多种生物学功能,如调节水盐代谢、调节免疫、防止肾结石产生和防止尿路感染等。近期全基因组关联分析发现编码尿调节素的基因UMOD启动子区单核苷酸多态性与慢性肾病的进展及预后具有很高关联度,并进一步通过孟德尔随机化方法证实尿调节素与慢性肾脏病的因果关系。     

Genome‐wide single nucleotide polymorphism‐based autozygosity mapping facilitates identification of mutations in consanguineous families with epidermolysis bullosa

Autozygosity mapping (AM) is a technique utilised for mapping homozygous autosomal recessive (AR) traits and facilitation of genetic diagnosis. We investigated the utility of AM for the molecular diagnosis of heterogeneous AR disorders, using epidermolysis bullosa (EB) as a paradigm. We applied this technique to a cohort of 46 distinct EB families using both short tandem repeat (STR) and genome‐wide single nucleotide polymorphism (SNP) array‐based AM to guide targeted Sanger sequencing of EB candidate genes. Initially, 39 of the 46 cases were diagnosed with homozygous mutations using this method. Independently, 26 cases, including the seven initially unresolved cases, were analysed with an EB‐targeted next‐generation sequencing (NGS) panel. NGS identified mutations in five additional cases, initially undiagnosed due to the presence of compound heterozygosity, deep intronic mutations or runs of homozygosity below the set threshold of 2 Mb, for a total yield of 44 of 46 cases (95.7%) diagnosed genetically.     

Causal assessment of sleep on coronary heart disease

ObjectiveSleep is an essential physiological process that protects our physical and mental health. However, the causality of the association between sleep and coronary heart disease (CHD) is unknown. Mendelian randomization (MR), using genetic variants as instrumental variables to test for causality, can infer credible causal associations. We applied a two-sample MR framework to determine the causal association between sleep (sleeplessness, sleep duration, and daytime dozing) and CHD by integrating summary-level genome-wide association study (GWAS) data.MethodsData included in this study were the GWAS summary statistics datasets from the C4D Consortium for CHD; Neale Lab UKB-a:13 Consortium for sleeplessness; Neale Lab UKB-a:9 Consortium for sleep duration and Neale Lab UKB-a:15 Consortium for daytime dozing. The conventional MR approach (inverse variance weighted, IVW) method and Egger method were used. Heterogeneity was calculated using each of the different MR methods where possible. Horizontal pleiotropy was evaluated by p-value of the MR–Egger intercept.ResultsThe IVW method estimate indicated that the odds ratio (OR) (95% confidence interval, CI) for CHD was 3.924 (1.345–11.447) per standard deviation increase in sleeplessness (p = 0.012). Results were consistent in MR–Egger method (OR, 4.654; 95% CI, 1.191–18.186; p = 0.009). The genetically predicted sleeplessness was positively casually associated with CHD. The causal association between sleep duration (or daytime dozing) and CHD was not established.ConclusionOur analysis provided evidence supporting a causal relationship between sleeplessness (not sleep duration or daytime dozing) and CHD.     

Obesity as a Causal Risk Factor for Aortic Valve Stenosis

BackgroundCausal risk factors for aortic valve stenosis are poorly understood, limiting the possibility of preventing the most common heart valve disease.ObjectivesThe hypothesis was tested that genetically based obesity measured by body mass index is causally associated with risk of aortic valve stenosis and replacement.MethodsThe authors included 108,211 individuals from the Copenhagen General Population Study. Participants had measurements of body mass index, waist-hip ratio, and waist circumference, and information on 5 genetic variants associated with obesity. A Mendelian randomization design was used to investigate genetic and observational associations of obesity with incident aortic valve stenosis (n = 1,215) and replacement (n = 467) for a median follow-up time of 8.7 years.ResultsGenetically increased body mass index was causally associated with increased risk of aortic valve stenosis. Compared with an unweighted allele score of 0 to 3, individuals with an allele score 7 to 10 had a mean increase in body mass index of 0.87 kg/m², and the age and sex–adjusted hazard ratio for aortic valve stenosis was 1.3 (95% confidence interval [CI]: 1.0 to 1.7) for allele score 4, 1.4 (95% CI: 1.1 to 1.8) for allele score 5 to 6, and 1.6 (95% CI: 1.3 to 2.1) for allele score 7 to 10 (p for trend: 9 × 10⁻⁵). A 1-kg/m² increase in body mass index was associated with causal risk ratios for aortic valve stenosis and replacement, respectively, of 1.52 (95% CI: 1.23 to 1.87) and 1.49 (95% CI: 1.07 to 2.08) genetically, and with corresponding hazard ratios of 1.06 (95% CI: 1.05 to 1.08) and 1.06 (95% CI: 1.03 to 1.08) observationally.ConclusionsObesity from human genetics was causally associated with higher risk of aortic valve stenosis and replacement.     

Short or Long Sleep Duration and CKD: A Mendelian Randomization Study

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Genetically predicted childhood obesity and adult atrial fibrillation: A mendelian randomization study

Background and aimsIt is unclear whether the association of childhood obesity with adult atrial fibrillation observed in observational studies reflects causal effects. The aim of this study was to evaluate the association of childhood obesity with adult atrial fibrillation using genetic instruments.Methods and resultsWe used a two-sample Mendelian randomization (MR) design to evaluate the association between childhood obesity and adult atrial fibrillation. Two sets of genetic variants (15 single nucleotide polymorphisms [SNPs] for childhood body mass index [BMI] and 12 SNPs for dichotomous childhood obesity) were selected as instruments. Summary data on SNP-childhood obesity and SNP-atrial fibrillation associations were obtained from recently published genome-wide association studies. Effect estimates were evaluated using inverse-variance weighted (IVW) methods. Other MR analyses, including MR-Egger, simple and weighted median, weighted MBE and MR-PRESSO methods were performed in sensitivity analyses.The IVW models showed that both a genetically predicted one-standard deviation increase in childhood BMI (kg/m²) and higher log-odds of childhood obesity were associated with a substantial increase in the risk of atrial fibrillation (OR = 1.22, 95% CI: 1.11–1.34, P < 0.001; OR = 1.09, 95% CI: 1.04–1.14, P < 0.001). MR-Egger regression showed no evidence of genetic pleiotropy for childhood BMI (intercept = 0.000, 95% CI: ?0.024 to 0.023), but for childhood obesity (intercept = ?0.036, 95% CI: ?0.057 to ?0.015). Similar results were observed using leave-one-out and other MR methods in sensitivity analyses.ConclusionsThis MR analysis found a consistent association between genetically predicted childhood obesity and an increased risk of adult atrial fibrillation. Further research is warranted to validate our findings.     

Visceral adipose tissue had a causal,independent role in lowering the risk of Parkinson's disease: A mendelian randomization study

Genetic evidence based on two-sample Mendelian randomization approaches suggested that visceral adipose tissue had a causal, independent role in lowering the risk of Parkinson's disease. Further studies are needed to explore the underlying mechanism.