The Cornus kousa tree, which is of Asian origin, is often cultivated for ornamental purposes and used in traditional medicine. The tree produces sugar-rich fruits, which are potential habitats for natural yeasts. The identification of new yeast strains has many advantages for the industry and research. This study aimed to isolate and identify yeast species from C. kousa fruits and to understand their microbial ecology. Ripe and rotten fruits, which had fallen on the ground naturally, were collected and soaked in culture media, followed by plate spreading for colony growth. The morphological examination revealed three distinct colony types, including two from the ripe fruits and one from the rotten fruits. The analysis of the internal transcribed spacer 1 region indicated three yeast strains corresponding to the three colony types: Torulaspora delbrueckii and Pichia kluyveri from the ripe fruits and Saccharomyces cerevisiae from the rotten fruits. The metabolic characterizations demonstrated that all three yeasts efficiently consumed glucose and produced alcohol. S. cerevisiae exhibited the strongest fermentation ability and the highest growth rate. These findings showed that Cornus kousa fruit is a source of diverse yeast species, with distinct species associated with different states of fruit decomposition.

With the rapid development of gene therapy technology in recent years, its abuse as a method of sports doping in athletics has become a concern. However, there is still room for improvement in gene-doping testing methods, and a robust animal model needs to be developed. Therefore, the purposes of this study were to establish a model of gene doping using recombinant adeno-associated virus vector-9, including the human erythropoietin gene (rAAV9-hEPO), and to establish a relevant testing method. First, it was attempted to establish the model using rAAV9-hEPO on mice. The results showed a significant increase in erythrocyte volume accompanied by an increase in spleen weight, confirming the validity of the model. Next, we attempted to detect proof of gene doping by targeting DNA and RNA. Direct proof of gene doping was detected using a TaqMan-qPCR assay with certain primers/probes. In addition, some indirect proof was identified in RNAs through the combination of a TB Green qPCR assay with RNA sequencing. Taken together, these results could provide the foundation for an effective test for gene doping in human athletes in the future.

Rapid advancements in gene technology have raised concerns regarding the potential abuse of techniques, such as gene doping, for enhancing athletic performance. To identify this possibility, a reliable procedure for detecting doping genes is required. Although detection methods for doping genes have been created, there are still areas for further improvement. One significant challenge is the high storage and transport costs of the test samples. For this issue, the dried blood spot (DBS) method can be a cost-effective solution. This study aimed to assess the practicality of incorporating DBSs into the gene doping detection process as a pilot study. Whole-blood samples were initially collected from mice engineered to express human erythropoietin from the rAAV vector. Then, the blood was placed in filter papers and left to dry at room temperature for five hours to form DBSs. These DBSs were subsequently preserved in sealed plastic bags at room temperature. After the extraction of DNA, DBSs were formed, and TaqMan-qPCR was utilized to detect the presence of rAAV vector-derived DNA. The finding confirmed that doping gene-specific fragments were successfully detected in DBSs. This outcome suggests that the DBS method is an effective approach to be considered when developing a comprehensive protocol for gene doping detection.

In recent years, as gene therapy technology has rapidly developed, there has been growing concern that it could be misused by athletes as a means of doping. However, current testing methods for gene doping have a range of limitations and require further improvement. Furthermore, significant progress has been made in the fields of blood storage, next-generation sequencing (NGS), and LabDroid (experimental robots). Against this background, this study was implemented to develop a test method for gene doping using dried blood spot (DBS), NGS, and the LabDroid ”Maholo”. As a first step, recombinant adeno-associated virus containing the human erythropoietin gene (hEPO) was injected into mice to establish a gene doping model. Subsequently, DBS was created using whole blood. Maholo was used to extract DNA from the DBS and to create DNA libraries for NGS. NGS in combination with bioinformatic analysis clearly identified DNA fragments that provided definitive evidence of gene doping in the mouse model, which were absent in the control mouse. To the best of our knowledge, this is the first attempt to use a biological model of hEPO gene doping in conjunction with Maholo, NGS, and DBS. This method should facilitate the further development of gene doping tests.

With the rapid development of gene therapy technology in recent years, its abuse as a method of sports doping in athletic has become a concern. However, there is still room for improvement in gene doping testing methods, and a robust animal model needs to be developed. Therefore, the purposes of this study were to establish a model of gene doping using recombinant adeno-associated virus vector-9 including the human erythropoietin gene (rAAV9-hEPO), and to establish a relevant testing method. First, it was attempted to establish the model using rAAV9-hEPO on mice. The results showed a significant increase in erythrocyte volume accompanied by an increase in spleen weight, confirming the validity of the model. Next, we attempted to detect proof of gene doping by targeting DNA and RNA. Direct proof of gene doping was detected using a TaqMan-qPCR assay with certain primers/probes. In addition, some indirect proof was identified in RNAs through the combination of a TB Green qPCR assay with RNA sequencing. Taken together, these results could provide the foundation for an effective test for gene doping in human athletes in the future.

Medical care for domestic dogs is now respected worldwide as being at a similar level to that of humans. We previously established a test method to determine whole mitochondrial DNA (mtDNA) using oral mucosal DNA that may be useful for medical care and welfare. However, the sample types tested in dogs are not limited to those obtained from the oral mucosa. Therefore, in the present study, we attempted to establish a test method to determine whole mtDNA sequences using feces, which represents the least invasive specimen. Two Japanese domestic dogs were used in the present study. DNA was extracted from approximately 100 mg of fresh feces from each dog, and PCRs were performed using four primer pairs that can amplify whole mtDNA. Following PCR, amplicons were pooled to create a DNA library using an experimental robot with an original program. Data were then acquired via NGS and data analysis was performed. The results showed that the whole mtDNA sequence of the two dogs was determined with high accuracy. Our results suggest that feces can be adapted for mitochondrial disease and individual identification testing and could serve as a useful testing method for the future medical care and welfare of domestic dogs.