Stories and Challenges of Genome Wide Association Studies in Livestock — A Review

Undoubtedly livestock is one of the major contributors to the economy of any country. The economic value of livestock includes meat, dairy products, fiber, fertilizer etc. Understanding and identifying the associations of quantitative trait loci (QTL) with the economically important traits is believed to substantially benefit the livestock industry. The past two decades have seen a flurry of interest in mapping the QTL associated with traits of economic importance on the genome. With the availability of single nucleotide polymorphism chip of various densities it is possible to identify regions, QTL and genes on the genome that explain the association and its effect on the phenotype under consideration. Remarkable advancement has been seen in genome wide association studies (GWAS) since its inception till the present day. In this review we describe the progress and challenges of GWAS in various livestock species

Genetic Evaluation of Carcass Traits of Commercial Steers at Different Slaughter End–points

Carcass records, including pedigree, for 10,441 steers born from 2003 to 2008 and 21,711 animals total, were made available by the Pyengchang Youngwal Jungsun Livestock Cooperative. Data for each trait were adjusted for each of 5 end-points: age (EPA), back fat (EPB), carcass weight (EPC), eye muscle area (EPE), and marbling score (EPM), and adjustments were made by fitting a linear. Genetic parameters were estimated using ASREML, which uses an average information algorithm. At different slaughter end-points, heritability estimates for CWT (range=0.25 to 0.37) and EMA (range=0.17 to 0.33) were more significantly different than heritability estimates for BF (range=0.41 to 0.42) and MS (range=0.40 to 0.45). Genetic correlations between BF and CWT, EMA and CWT, and EMA and MS were positive, and those between BF and EMA and BF and MS were negative. The genetic correlation between CWT and MS yielded conflicting results. Correlations of sire breeding value for BF, CWT, EMA, and MS were in the range of 0.91 to 0.99, 0.75 to 0.93, 0.72 to 0.95, and 0.90 to 0.99, respectively, and those of the dam were in the range of 0.90 to 0.97, 0.73 to 0.94, 0.71 to 0.94, and 0.91 to 0.99, respectively. Further study will be needed to determine whether these alternative end-points result in a more accurate estimate of BV than the traditional age end-point

Deferral vs. performance of percutaneous coronary intervention of functionally non-significant coronary stenosis : 15-year follow-up of the DEFER trial

AIMS: Stenting an angiographically intermediate but functionally non-significant stenosis is controversial. Nevertheless, it has been questioned if deferral of a functionally non-significant lesion on the basis of fractional flow reserve (FFR) measurement, is safe, especially on the long term. Five-year follow-up of the DEFER trial showed that outcome after deferral of percutaneous coronary intervention (PCI) of an intermediate coronary stenosis based on FFR ≥ 0.75 is excellent and was not improved by stenting. The aim of this study was to investigate the validity of this position on the very long term. METHODS AND RESULTS: In 325 patients scheduled for PCI of an intermediate stenosis, FFR was measured just before the planned intervention. If FFR was ≥0.75, patients were randomly assigned to deferral (Defer group; n = 91) or performance (Perform group; n = 90) of PCI. If FFR was <0.75, PCI was performed as planned (Reference group; n = 144). Clinical follow-up was 15 years. There were no differences in baseline clinical characteristics between the randomized groups. Complete 15-year follow-up was obtained in 92% of patients. After 15 years of follow-up, the rate of death was not different between the three groups: 33.0% in the Defer group, 31.1% in the Perform group, and 36.1% in the Reference group (Defer vs. Perform, RR 1.06, 95% CI: 0.69-1.62, P = 0.79). The rate of myocardial infarction was significantly lower in the Defer group (2.2%) compared with the Perform group (10.0%), RR 0.22, 95% CI: 0.05-0.99, P = 0.03. CONCLUSION: Deferral of PCI of a functionally non-significant stenosis is associated with a favourable very long-term follow-up without signs of late 'catch-up' phenomenon

Inodilators May Improve the In-Hospital Mortality of Patients with Cardiogenic Shock Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation

Although inodilators (dobutamine and milrinone) are widely used empirically for cardiogenic shock (CS), the efficacy of inodilators for patients with CS undergoing veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is controversial. We evaluated the effects of inodilators on clinical outcomes using the RESCUE (REtrospective and prospective observational Study to investigate Clinical oUtcomes and Efficacy of left ventricular assist device for Korean patients with cardiogenic shock; NCT02985008) registry. We selected and analyzed the clinical outcomes of 496 patients who underwent VA-ECMO and did or did not receive inodilators. Of the 496 patients, 257 (51.8%) died during hospitalization. We selected 191 matched pairs to adjust for baseline clinical characteristics after 1:1 propensity score matching (PSM). The univariate and multivariate analyses showed that the inodilator group had significantly lower in-hospital mortality than the no-inodilator group (unadjusted hazard ratio [HR], 0.768; 95% confidence interval [CI], 0.579&ndash;1.018; p = 0.066, adjusted HR, 0.702; 95% CI, 0.552&ndash;0.944; p = 0.019). For patients with CS undergoing VA-ECMO, inodilators may improve clinical outcomes

Deferral vs. performance of percutaneous coronary intervention of functionally non-significant coronary stenosis:15-year follow-up of the DEFER trial

\u3cp\u3eAims Stenting an angiographically intermediate but functionally non-significant stenosis is controversial. Nevertheless, it has been questioned if deferral of a functionally non-significant lesion on the basis of fractional flow reserve (FFR) measurement, is safe, especially on the long term. Five-year follow-up of the DEFER trial showed that outcome after deferral of percutaneous coronary intervention (PCI) of an intermediate coronary stenosis based on FFR = 0.75 is excellent and was not improved by stenting. The aim of this study was to investigate the validity of this position on the very long term. Met hods and resul ts In 325 patients scheduled for PCI of an intermediate stenosis, FFR was measured just before the planned intervention. If FFR was = 0.75, patients were randomly assigned to deferral (Defer group; n = 91) or performance (Perform group; n = 90) of PCI. If FFR was, 0.75, PCI was performed as planned (Reference group; n = 144). Clinical follow-up was 15 years. There were no differences in baseline clinical characteristics between the randomized groups. Complete 15-year follow-up was obtained in 92% of patients. After 15 years of follow-up, the rate of death was not different between the three groups: 33.0% in the Defer group, 31.1% in the Perform group, and 36.1% in the Reference group (Defer vs. Perform, RR 1.06, 95% CI: 0.69 1.62, P = 0.79). The rate of myocardial infarction was significantly lower in the Defer group (2.2%) compared with the Perform group (10.0%), RR 0.22, 95% CI: 0.05 0.99, P = 0.03. Conclusion Deferral of PCI of a functionally non-significant stenosis is associated with a favourable very long-term follow-up without signs of late 'catch-up' phenomenon.\u3c/p\u3