Evaluation of non-additive genetic effects on carcass and meat quality traits in Korean Hanwoo cattle using genomic models.

The traditional genetic evaluation methods generally consider additive genetic effects only and often ignore non-additive (dominance and epistasis) effects that may have contributed to genetic variation of complex traits of livestock species. The available dense single nucleotide polymorphisms (SNPs) panels offer to investigate the potential benefits of including non-additive genetic effects in the genomic evaluation models. Data from 16 971 genotyped (Illumina Bovine 50 K SNP chip) Korean Hanwoo cattle were used to estimate genetic variance components and prediction accuracy of genomic breeding values (GEBVs) for four carcass and meat quality traits: carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT) and marbling score (MS). Five different genetic models were evaluated through including additive, dominance and epistatic interactions (additive by additive, A × A; additive by dominance, A × D and dominance by dominance, D × D) successively in the models. The estimates of additive genetic variances and narrow sense heritabilities (ha2) were found similar across the evaluated models and traits except when additive interaction (A × A) was included. The dominance variance estimates relative to phenotypic variance ranged from 1.7-3.4% for CWT and MS traits, whereas, they were close to zero for EMA and BFT traits. The magnitude of A × A epistatic heritability (haa2) ranged between 14.8 and 27.7% in all traits. However, heritability estimates for A × D and D × D epistatic interactions (had2 and hdd2) were quite low compared to haa2 and were contributed only 0.0-9.7% of the total phenotypic variation. In general, broad sense heritability (hG2) estimates were almost twice (ranging between 0.54 and 0.68) the ha2 for all of the investigated traits. The inclusion of dominance effects did not improve the prediction accuracy of GEBV but improved 2.0-3.0% when epistatic effects were included in the model. More importantly, rank correlation revealed that partitioning of variance components considering dominance and epistatic effects in the model would enable to re-rank of top animals with better prediction of GEBV. The present result suggests that dominance and epistatic effects could be included in the genomic evaluation model for better estimates of variance components and more accurate prediction of GEBV for carcass and meat quality traits in Korean Hanwoo cattle.

Effectiveness of next-generation sequencing for patients with advanced non-small-cell lung cancer: a population-based registry study.

BACKGROUND: Despite the growing use of next-generation sequencing (NGS) in the management of advanced non-small-cell lung cancer (NSCLC), there is little evidence that its use leads to improved clinical outcomes. This study aimed to compare the effectiveness of NGS with that of single-gene testing (SGT) alone in patients with advanced NSCLC. MATERIALS AND METHODS: This was a retrospective cohort study conducted on patients diagnosed with advanced lung adenocarcinoma between 2017 and 2018 from a nationwide, population-based database. We identified patients who had SGT exclusively (SGT group) or underwent upfront NGS or NGS following SGT as an initial evaluation (NGS group). Patients were followed up until death or the end of the study (31 December 2019). The adjusted hazard ratio (aHR) for death was estimated using the Cox proportional hazards model. The factors affecting the adoption of NGS were identified. RESULTS: Of 8566 patients diagnosed with advanced lung adenocarcinoma, 402 and 6932 patients were assigned to the NGS and SGT groups, respectively. More NGS was carried out in younger patients, those with higher incomes, and those living in urban areas. After balancing these confounders through matching, no difference was observed in the median overall survival and risk of death between the NGS and SGT groups [18.5 versus 19.7 months, log-rank P = 0.783; aHR 0.98, 95% confidence interval (CI) 0.84-1.14, respectively]. Only in a subgroup for whom epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitors were not indicated, NGS was associated with better survival outcomes (14.1 versus 9.0 months, log-rank P = 0.006; aHR 0.82, 95% CI 0.69-0.97). CONCLUSIONS: In the real world, NGS for all-comers in patients with advanced NSCLC did not increase survival outcomes. When health care resources to support equal access to NGS are limited, upfront SGT followed by NGS may be a more efficient strategy.