Epidemiology and Genetic Diversity of PCV2 Reveals That PCV2e Is an Emerging Genotype in Southern China: A Preliminary Study

Porcine circovirus-associated disease (PCVAD), caused by porcine circovirus type 2 (PCV2), has ravaged the pig industry, causing huge economic loss. At present, PCV2b and PCV2d are highly prevalent genotypes worldwide, while in China, in addition to PCV2b and PCV2d, a newly emerged PCV2e genotype detected in the Fujian province has attracted attention, indicating that PCV2 genotypes in China are more abundant. A preliminary study was conducted to better understand the genetic diversity and prevalence of PCV2 genotypes in southern China. We collected 79 random lung samples from pigs with respiratory signs, from 2018 to 2021. We found a PCV2-positivity rate of 29.1%, and frequent co-infections of PCV2 with PCV3, Streptococcus suis (S. suis), and other porcine pathogens. All PCV2-positive samples were sequenced and subjected to whole-genome analysis. Phylogenetic analysis, based on the PCV2 ORF2 gene and complete genomes, found that PCV2 strains identified in this study belonged to genotypes PCV2a (1), PCV2b (6), PCV2d (10), and PCV2e (6). Importantly, PCV2e was identified for the first time in some provinces, including Guangdong and Jiangxi. Additionally, we found two positively selected sites in the ORF2 region, located on the previously reported antigenic epitopes. Moreover, codon 63, one of the positively selected sites, has different types of amino acids in different genotypes. In conclusion, this study shows that PCV2e is an emerging genotype circulating in southern China, which warrants urgent, specific surveillance to aid the development of prevention and control strategies in China.     

Nucleic acid‐based non‐invasive prenatal diagnosis of genetic skin diseases: are we ready?

The discovery of circulating fetal nucleic acids is a great step on the way of developing non‐invasive prenatal diagnosis (NIPD) for genetic disorders. Here, we briefly discuss the current applications of circulating fetal nucleic acids in genetic testing for different kinds of hereditary diseases with an emphasis on using circulating cell‐free fetal DNA in diagnosis of monogenic disorders. As the genetic skin disorders impair the quality of life at different levels, we next discuss some ethical issues in NIPD for genetic skin diseases of various severities and in particular, the responsibility of doctors and parents, respectively, in the prenatal genetic testing.     

Association of maternal AGTR1 polymorphisms and preeclampsia: a systematic review and meta-analysis

Objective: Systematic review and meta-analysis to investigate the association between maternal AGTR1 gene single nucleotide polymorphisms (SNPs) and preeclampsia (PE). Methods: A systematic literature search was performed using PubMed, EMBASE, Scopus, and HuGE Literature Finder databases. The review was conducted according to PRISMA guidelines. Summary odds ratios (ORs) for the allelic and genotypic contrasts were calculated and compared to indicate the most appropriate genetic model for the polymorphism of interest. Among-study heterogeneity was assessed using the I² statistic and publication bias was evaluated visually using funnel plots. Results: Seven maternal SNPs investigated with PE were found, but only AGTR1 +1166A>C accumulated sufficient evidence for meta-analysis. Summary ORs calculated from eight studies (10 populations involving 845 PE cases and 1150 controls) did not reveal an association between the +1166A>C polymorphism and PE (allelic OR = 1.19, 95% CI: 0.96–1.47). No evidence of publication bias and among-study heterogeneity was detected. Conclusions: meta-analysis findings did not support AGTR1 +1166A>C as a susceptibility locus for PE. Other AGTR1 SNPs require more study.     

石油作业习惯性流产女性的细胞遗传毒理学研究

目的分析石油作业女性外周血细胞姐妹染色单体互换（SCE）与习惯性流产的关系。方法随机选择习惯性流产的石油作业女性20名和健康育龄女性20名,检测其外周血细胞SCE发生率。结果实验组外周血淋巴细胞SCE发生率为（8.43±1.65）%,明显高于健康对照组（P〈0.05）。结论 SCE的发生降低了染色体结构的稳定性,并与石油作业女性习惯性流产有关。     

Genetic susceptibility and mechanisms for refractive error

Refractive errors, myopia and hyperopia, are the most common causes of visual impairment worldwide. Recent advances in genetics have been utilized to identify a wealth of genetic loci believed to contain susceptibility genes for refractive error (RE). The current genetic evidence confirms that RE is influenced by both common and rare variants with a significant environmental component. These studies argue that only by combining genetic and environmental knowledge with in vivo measurements of biological states will it be possible to understand the underlying biology of RE that will lead to novel therapeutic targets and accurate genetic predictions.     

Drift-barrier hypothesis and mutation-rate evolution

Mutation dictates the tempo and mode of evolution, and like all traits, the mutation rate is subject to evolutionary modification. Here, we report refined estimates of the mutation rate for a prokaryote with an exceptionally small genome and for a unicellular eukaryote with a large genome. Combined with prior results, these estimates provide the basis for a potentially unifying explanation for the wide range in mutation rates that exists among organisms. Natural selection appears to reduce the mutation rate of a species to a level that scales negatively with both the effective population size (N_e), which imposes a drift barrier to the evolution of molecular refinements, and the genomic content of coding DNA, which is proportional to the target size for deleterious mutations. As a consequence of an expansion in genome size, some microbial eukaryotes with large N_e appear to have evolved mutation rates that are lower than those known to occur in prokaryotes, but multicellular eukaryotes have experienced elevations in the genome-wide deleterious mutation rate because of substantial reductions in N_e.     

Plugging the leak: Emergency response to global crisis

People can be easily exposed to manganese (Mn), the twelfth most abundant element, through various exposure routes. However, overexposure to Mn causes manganism, a motor syndrome similar to Parkinson disease, via interference of the several neurotransmitter systems, particularly the dopaminergic system in areas. At cellular levels, Mn preferentially accumulates in mitochondria and increases the generation of reactive oxygen species, which changes expression and activity of manganoproteins. Many studies have provided invaluable insights into the causes, effects, and mechanisms of the Mn-induced neurotoxicity. To regulate Mn exposure, many countries have performed biological monitoring of Mn with three major biomarkers: exposure, susceptibility, and response biomarkers. In this study, we review current statuses of Mn exposure via various exposure routes including food, high susceptible population, effects of genetic polymorphisms of metabolic enzymes or transporters (CYP2D6, PARK9, SLC30A10, etc.), alterations of the Mn-responsive proteins (i.e., glutamine synthetase, Mn-SOD, metallothioneins, and divalent metal trnsporter1), and epigenetic changes due to the Mn exposure. To minimize the effects of Mn exposure, further biological monitoring of Mn should be done with more sensitive and selective biomarkers.     

History of vaccination

Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before.     

Women’s use of online resources and acceptance of e-mental health tools during the perinatal period

ObjectivesThe women’s professional help-seeking rate for perinatal depression is low, despite the prevalent and disabling nature of this condition. Therefore, new approaches should be implemented to increase women’s access and utilization of treatment resources, namely e-mental health tools. This study aimed to characterize women’s current pattern of use of online resources for mental heal issues and women’s acceptance of e-mental health tools during the perinatal period, and to investigate its main determinants.MethodsThis study used an online cross-sectional survey that was completed by 546 women during the perinatal period.Results31.3% had prior knowledge of websites targeting mental health illness. Women presenting an actual need for help (i.e., a positive screen for depression) reported greater use of online resources and greater engagement in e-health behaviors related to mental health (d = 0.46–0.61), and being more accepting of e-mental health tools, particularly of informative websites. Women’s perceptions concerning the e-mental tools were found to predict their intentions to use them.ConclusionsThe results seem to globally support Portuguese women’s acceptance of e-mental health tools. To improve the level of acceptance, women should be involved as stakeholders in the development of new e-mental health tools and provided with specific information before their utilization.