Samples of domestically distributed soybeans from Brazil produced in 2021 and 2022 were analyzed using 17 event-specific and 2 screening detection methods for genetically modified (GM) soybeans. We found that the detected varieties of GM soybeans from Brazil were significantly different from those observed in our previous study on GM soybeans imported from the United States and Canada within the same years [Soga et al., GM Crops & Food, 16, 116-125 (2025)]. After analyzing five different lots for each year, RRS, MON89788, and MON87701 were detected in all lots, whereas MON87708 and MON87751 were detected in four lots. RRS, MON89788, MON87701, MON87708 and MON87751 are a glyphosate tolerant, a glyphosate tolerant, an insect resistant, a glyphosate and dicamba tolerant, and an insect resistant GM soybean, respectively. Single kernel-based analyses revealed that stacked varieties, including MON89788 and MON87701, comprised a large proportion of GM soybeans from Brazil.

The number of authorized genetically modified (GM) soybeans has increased worldwide. In Japan, 34 GM soybeans containing single events and their stacked varieties have been approved as food. However, not all approved GM events are commercially cultivated or distributed. In this study, we evaluated domestically distributed samples from the United States (US) and Canada using 17 event-specific detection methods for GM soybeans. Identity-preserved (IP) soybean samples imported from the US and Canada, and non-IP samples from the US in 2021 and 2022 were analyzed. Four GM soybean events consisting of MON89788, A5547-127, MON87708, and DAS-44406 were detected in all lots in the non-IP samples. Furthermore, a single-kernel-based analysis was conducted to determine whether the detected GM soybean events are stacked. The results suggest that DAS-44406 is rapidly increasing, particularly as a single event among GM soybeans.

In March 2023, unapproved genetically modified (GM) squashes were discovered in South Korea. These were thought to be GM squash ZW20 and CZW3, which are approved for use as food only in Canada and the United States. Because the safety of ZW20 and CZW3 has not been evaluated in Japan, they must continue to be monitored to prevent their unintentional import. In this study, we developed and validated real-time PCR-based qualitative detection methods for ZW20 and CZW3. We evaluated these two detection methods on the basis of PCR amplification efficiency, limit of detection, specificity, and reproducibility to determine their utility for distinguishing and identifying ZW20 and CZW3. One method detects the zucchini yellow mosaic virus resistance gene (ZYMV-coat protein: ZYMV-cp) sequence present in both ZW20 and CZW3, whereas the other method detects the cucumber mosaic virus resistance gene (CMV-coat protein: CMV-cp) sequence present only in CZW3. Our results showed that the ZYMV-cp and CMV-cp detection methods are highly specific for GM squash ZW20 and CZW3, and are sufficiently sensitive, capable of detecting transgenes with at least 6.3 and 3.1 copies per reaction, respectively. Based on this study, we developed the official detection method for GM squash in Japan by combining the ZYMV-cp and CMV-cp detection methods to discriminate between ZW20 and CZW3, making it useful for monitoring food safety.

Cells regularly repair numerous mutations. However, the effect of CRISPR/Cas9-induced dsDNA breaks on the repair processes of naturally occurring genome-wide mutations is unclear. In this study, we used TSCE5 cells with the heterozygous thymidine kinase genotype (TK+/-) to examine these effects. We strategically inserted the target sites for guide RNA (gRNA)/Cas9 and I-SceI into the functional allele and designed the experiment such that deletions of > 81 bp or base substitutions within exon five disrupted the TK gene, resulting in a TK-/- genotype. TSCE5 cells in the resting state exhibited 16 genome-wide mutations that affected cellular functions. After gRNA/Cas9 editing, these cells produced 859 mutations, including 67 high-impact variants that severely affected cellular functions under standard culture conditions. Mutation profile analysis indicated a significant accumulation of C to A substitutions, underscoring the widespread induction of characteristic mutations by gRNA/Cas9. In contrast, gRNA/Cas9-edited cells under conditions of S∼G2/M arrest and cyclin-dependent kinase 1 inhibition showed only five mutations. Transcriptomic analysis revealed the downregulation of DNA replication genes and upregulation of alternative DNA repair genes, such as zinc finger protein 384 (ZNF384) and dual specificity phosphatase, under S∼G2/M conditions. Additionally, activation of nucleotide and base excision repair gene, including O-6-methylguanine-DNA methyltransferase and xeroderma pigmentosum complementation group C, was observed. This study highlights the profound impact of CRISPR/Cas9 editing on genome-wide mutation processes and underscores the emergence of novel DNA repair pathways. Finally, our findings provide significant insights into the maintenance of genome integrity during genome editing.

Although the safety of genome-edited foods in Japan has been confirmed through pre-submission consultation under the notification process, public perception of safety confirmation methodology has not been investigated to date. Therefore, we created three media to provide information on the safety assurance of genome-edited foods and surveyed the perception of current safety confirmation. In addition, we examined the opinions of researchers in health science on current safety confirmation methods. As a result, 62% of general consumers and 68% of researchers in health science recognized that safety is ensured. Acceptance of genome-edited foods improved when they realized that safety was ensured. Researchers in health science who felt that safety confirmation was insufficient were concerned about the third-party verification. Therefore, it was suggested that in order to boost public understanding of genome-edited foods, it would be useful to inform the public by communicating in an easy-to-understand way the safety assurance approaches being made in pre-submission consultation.

In the Japanese official detection method for unauthorized genetically modified (GM) papayas, one of two types of real-time PCR reagents with DNA polymerase (TaqMan Gene Master Mix [TaqMan Gene] or FastGene QPCR Probe Mastermix w/ROX [FastGene]) is primarily used for measurement. In 2022, we conducted a laboratory performance study on the unauthorized GM papaya line PRSV-YK, and the results revealed that high threshold cycle (Cq) values for the PRSV-YK detection test were obtained using TaqMan Gene with the 7500 Fast & 7500 Real-Time PCR System (ABI7500) and QuantStudio 12K Flex (QS12K), indicating the possibility of false negatives. The possibility of similar problems with all unauthorized GM papaya lines detection tests needs to be evaluated. In this study, we performed detection tests on unauthorized GM papaya lines (PRSV-YK, PRSV-SC, and PRSV-HN), the cauliflower mosaic virus 35S promotor (CaM), and a papaya positive control (Chy), and examined how the limits of detection (LOD) for each test are affected by two types of DNA polymerases (TaqMan Gene and FastGene) and three types of real-time PCR instruments (ABI7500, QS12K, and LightCycler 480 Instrument II [LC480]). In the PRSV-YK and PRSV-SC detection tests using ABI7500 and QS12K, measurement with TaqMan Gene showed a higher LOD than FastGene. In this case, an exponential amplification curve was confirmed on the amplification plot; however, the amplification curve did not cross the ΔRn threshold line and the correct Cq value was not obtained with a threshold line=0.2. The other tests (PRSV-HN, CaM, and Chy with ABI7500 and QS12K, and all detection tests with LC480) showed no important differences in the LOD for each test using either DNA polymerase. Therefore, when performing PRSV-YK and PRSV-SC detection tests with the ABI7500 or QS12K, FastGene should be used to avoid false negatives for foods containing GM papaya lines PRSV-YK and PRSV-SC at low mixing levels.

Since the establishment of procedures for the safety assessment of food products that use recombinant DNA technology, the manufacture, import, and sale of genetically modified (GM) foods that have not undergone safety assessment are prohibited under the Food Sanitation Act. Therefore, a performance study to confirm the GM food testing operations of each laboratory is very important to ensure the reliability of the GM food monitoring system. In 2022, GM papaya line PRSV-YK-which has not yet been authorized in Japan-was selected for testing, and a papaya paste and a DNA solution were used as the test samples. With these samples, a laboratory performance study of the DNA extraction and real-time PCR operations was conducted. This confirmed that the 18 participating laboratories were generally performing the DNA extraction and real-time PCR operations correctly. However, some laboratories using certain DNA amplification reagent with some real-time PCR instruments were not able to determine the PRSV-YK detection test. This suggests that the PRSV-YK detection test may not be able to correctly detect samples containing GM papaya when performed with these combinations of instruments and reagent. In order to ensure the reliability of the PRSV-YK detection test, it is necessary to examine in detail how the combination of DNA polymerase reagents and real-time PCR instruments affects the detection limit, and to implement an appropriate solution.

Carotenoid intake is associated with low mortality and cancer risks; data on non-provitamin carotenoid intake is limited especially in Asians. We aimed to estimate carotenoid intake in Japanese adult women. Carotenoid content database comprises 196 food items, including 39 fruits, 87 vegetables and mushrooms, and 11 seaweeds, and was established using data from the literature and analyses of foods available in Japan. We surveyed the intake of these foods in Japanese women aged 21-56 years (n=109). Total intake of 7 carotenoids (mean±SD [range]) was 7,450±3,840 (1,160-21,300) μg/day; α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, lycopene, and fucoxanthin represented 4.3%, 23%, 3.4%, 15%, 2.0%, 39%, and 13% of total intake, respectively. Lutein intake was 1,132±686 (294-3,490) μg/day; its best sources were spinach, cucumber, chicken egg, green onion, and Chinese chives, representing 51% of total intake. Lutein can be obtained from a variety of sources. Thus, lutein intake levels did not vary widely among individuals and very few individuals consumed insufficient levels of lutein. Intake of zeaxanthin, lycopene, and fucoxanthin was 149±93 (2-479), 2,890±2,970 (0-17,100), and 980±1,230 (0-5,660) μg/day, respectively. Their intake required rich sources including chicken egg for zeaxanthin (52%); tomato products for lycopene (98%), and wakame seaweed for fucoxanthin (76%). The carotenoid content database including all food items consumed in Japan will be helpful for further investigations on carotenoid intake and its health benefits.

The Japanese Health Ministry recently granted permission for the market distribution of genome-edited (GE) foods, yet there remains a lack of full understanding among consumers regarding this technology. In this study, we conducted a survey to assess the acceptability of GE foods among Japanese consumers and examined the impact of providing information about GE foods on their acceptability. We conducted a web-based survey among 3,408 consumers aged 20-69 years, focusing on three aspects: (1) the commercial availability of GE foods, (2) the consumption of GE foods by others, and (3) your own consumption of GE foods. The survey findings revealed that participants were most accepting of the consumption of GE foods by others, followed by their acceptance of GE foods being commercially available. Notably, participants' acceptance of GE foods increased in all three aspects after they viewed an informative video. The video had a particularly strong impact on participants who fully or partially understood its content, compared to those who did not. Furthermore, regression analyses showed that participants' understanding of two key areas, namely "Why are GE foods important" and "What procedures are in place to ensure the safety of GE foods," played a crucial role in increasing acceptability. Overall, these results indicate that providing information about GE foods to Japanese consumers can effectively enhance their acceptance of such foods. The findings highlight the importance of understanding the benefits and safety measures associated with GE foods in influencing consumer attitudes.

Strawberry contains many bioactive compounds such as vitamin C and polyphenols as well as folate, a vitamin that is especially important for women of childbearing age. We investigated the effects of the acute consumption of strawberry on the serum levels of vitamin C and folate, and on the antioxidant potential of low-density lipoprotein (LDL). In a randomised, placebo-controlled, double-blind, crossover study, twenty-three healthy female volunteers (age 22⋅5 ± 1⋅4 years) ingested 500 g of a strawberry purée beverage or a sugar content-matched placebo beverage. Blood samples were collected at fasting and at 0⋅5, 1, 2 and 4 h post-ingestion. The serum concentrations of vitamin C and folate were significantly elevated from 0⋅5 to 4 h after the strawberry beverage ingestion (P < 0⋅001); the levels peaked at 2 h, with peak levels of 15⋅0 ± 2⋅5 μg/ml for vitamin C and 14⋅4 ± 7⋅0 ng/ml for folate. Notably, at 1 h after the strawberry beverage ingestion, the LDL oxidation lag time was significantly prolonged (P < 0⋅05), suggesting that the antioxidant potential of LDL was increased. After the ingestion of either beverage, the serum levels of glucose and insulin reached a peak at 0⋅5 h and then quickly returned to baseline levels. These results suggest that strawberries are a useful source of vitamin C and folate and may help enhance the antioxidant potential of LDL in healthy young women.

Given that the number of genetically modified (GM) maize events that have been announced as having undergone safety assessment procedures in Japan is increasing yearly, more information is needed about their actual recent domestic distribution in Japan. In this study, we investigated whether current Japanese official qualitative and quantitative methods (the current official methods) for GM maize can comprehensively target events in domestically distributed maize. For samples with the identity-preserved (IP) handling system and non-IP samples from the United States (US) and non-IP samples from Brazil, we performed event-specific real-time PCR targeting 25 authorized single GM maize events in addition to the current official methods. According to our results, 15 events targeted by the current official methods were detected, but insect-resistance (IR) Event5307 and herbicide-tolerant (HT) DAS40278, not targeted by the current official methods, were detected in the US (one out of 5 lots) and Brazilian (four out of 5 lots) non-IP samples, respectively. Nevertheless, a survey of recent GM maize acreage in recent years has revealed that more than 95% of the acreage in US maize is occupied by HT or IR/HT stacked events, and that more than 95% of the acreage in Brazilian maize is occupied by IR or IR/HT stacked events. Because the current official methods can target all stacked events related to Event5307 and DAS40278, the only undetectable events are the single Event5307 and DAS40278, whose production is estimated to be less than 5% of the total production in the producing country. Therefore, we conclude that the current official methods for the labelling of GM maize should be maintained in view of practicability.

The food supply system is facing important challenges and its sustainability has to be considered. Genome-editing technology, which accelerates the development of new variety, could be used to achieve sustainable development goals, thereby protecting the environment and ensuring the stable production of food for an increasing global population. The most widely used genome-editing tool, CRISPR/Cas9, is easy to use, affordable, and versatile. Foods produced by genome-editing technologies have been developed worldwide to create novel traits. In the first half of the review, the latest scientific findings on genome-editing technologies are summarized, and the technical challenge in genome sequence analysis are clarified. CRISPR/Cas9 has versatile alternative techniques, such as base editor and prime editor. Genome sequencing technology has developed rapidly in recent years. However, it is still difficult to detect large deletions and structural variations. Long-read sequencing technology would solve this challenge. In the second part, regulatory framework and approach for genome-edited foods is introduced. The four government ministries, including the Ministry of Environment, the Ministry of Agriculture, Forestry and Fisheries, and the Ministry of Health, Labour and Welfare (MHLW), started to discuss how the regulation should be implemented in 2019. The SDN-1 technique is excluded from the current genetically modified organism (GMO) regulation. The Japanese regulatory framework includes pre-submission consultation and submission of notification form. In the last part of this review, transparency of regulatory framework and consumer confidence were described. Since maintaining consumer trust is vital, transparency of regulatory framework is a key to consumers. The information of notification process on approved genome-edited foods is made public immediately. This review will help regulators build regulatory frameworks, and lead to harmonization of the framework between the countries.

Estimations of individuals' polyphenol intake contributes to the understanding of the health benefits of dietary polyphenol. We developed a food frequency questionnaire for polyphenol intake (FFQ) and a short-form FFQ for polyphenol intake (SF-FFQ) for assessing the polyphenol intake of Japanese. The aim of this study was to compare the relative validity of polyphenol intake derived from the FFQ with that from the SF-FFQ, using a 4-consecutive-d dietary record (DR) as the reference. Sixty Japanese subjects aged 30-69 y completed the 4-d DR and the two FFQs regarding their polyphenol intake in November 2019. The polyphenol intake values estimated by the DR, FFQ, and SF-FFQ were 1,057±524 mg/d, 1,061±537 mg/d and 1,015±491 mg/d, respectively. No significant differences were present in the estimated polyphenol intake between the 4-d DR and both FFQs. The correlation coefficient with the DR was 0.779 for the FFQ and 0.814 for the SF-FFQ. These results indicate that the total polyphenol intake in a Japanese population were accurately estimated by the FFQ and SF-FFQ.

Yoichi Fukushima 1 Yoshinari Takahashi Yoshimi Kishimoto 3 Chie Taguchi Norie Suzuki Mihoko Yokoyama 4 Kazuo Kondo 1Wellness Communications Section, Nestlé Japan Ltd., Tokyo, Japan; 2Inary Corp., Tokyo, Japan; 3Endowed Research Department “Food for Health”, Ochanomizu University, Tokyo, Japan; 4Yokoyama Skin Clinic, Tokyo, Japan; 5Institute of Life Innovations Studies, Toyo University, Gunma, Japan Purpose: Hyperpigmentation of the skin can occur at any age depending on etiological factors but its intensity increases during adolescence in Japanese females and gradually develops further in adults. The purpose of this study was to characterize factors that influence skin hyperpigmentation, including age, skin type and dietary polyphenol sources. Patients and Methods: A cross-sectional survey of healthy Japanese women aged from 30 to 60 years (n=244) was conducted using food and environmental questionnaires and a VISIATM facial photoimage analyzer. Results: UV Pigmented Spot (PS) scores correlated negatively with the consumption of total polyphenols (TPs) (R=−0.224, p<0.001) and the rate of hyperpigmented spot development (PS score/age after 18 years of age) was suppressed by the consumption of TPs. This trend was independent of the melanin index and the skin type, which indicates the ability of the skin to tan after sun exposure. Consumption of coffee, the largest source of TPs, suppressed the PS score (p<0.001). Consumption of green tea, the second largest source of TPs, also suppressed the PS score, which was weaker than coffee but was statistically significant (p=0.029). The PS score was suppressed the most in subjects with both a high consumption of coffee and green tea. Conclusion: Higher consumption of TPs may be beneficial to alleviate photoaging of the skin, and coffee as well as green tea contribute to suppress skin hyperpigmentation through adding large amounts of TPs in the diet.

Green tea and coffee contain various bioactive compounds (e.g., polyphenols), and their consumption has been proposed to decrease the risk of cardiovascular diseases. Here, we investigated the associations between the consumption of green tea and that of coffee and the prevalence of coronary artery disease (CAD) in Japanese patients. The study group was 612 patients who underwent coronary angiography at Tokyo Medical Center between July 2008 and February 2017. CAD was confirmed in 388 of the patients: one-vessel disease (1-VD, n=166); two-vessel disease (2-VD, n=112); three-vessel disease (3-VD, n=110). Myocardial infarction (MI) was found in 138 patients. After adjustment for well-known atherosclerotic risk factors and other dietary habits, greater green tea consumption was significantly inversely associated with CAD prevalence (p for trend=0.044), and the patients who drank >3 cups/d had a lower prevalence of CAD compared to those who drank <1 cup/d (odds ratio [OR]: 0.54, 95% CI: 0.30-0.98). Greater green tea consumption (>3 cups/d) was also associated with a decreased prevalence of 3-VD (OR: 0.49, 95% CI: 0.24-0.98, p-trend=0.047) and MI (OR: 0.51, 95% CI: 0.27-0.97, p-trend=0.037). In contrast, coffee consumption was not associated with CAD or MI. In subgroup analyses, the inverse association between green tea consumption and CAD or MI was found in the high intake groups of vegetables or fruits but not in the low intake groups of vegetables or fruits. These results suggest a beneficial effect of green tea consumption, especially with a diet rich in vegetables and fruits, against coronary atherosclerosis in Japanese.

Purpose: Hyperpigmentation of the skin can occur at any age depending on etiological factors but its intensity increases during adolescence in Japanese females and gradually develops further in adults. The purpose of this study was to characterize factors that influence skin hyperpigmentation, including age, skin type and dietary polyphenol sources. Patients and Methods: A cross-sectional survey of healthy Japanese women aged from 30 to 60 years (n=244) was conducted using food and environmental questionnaires and a VISIAT facial photoimage analyzer. Results: UV Pigmented Spot (PS) scores correlated negatively with the consumption of total polyphenols (TPs) (R=-0.224, p<0.001) and the rate of hyperpigmented spot development (PS score/age after 18 years of age) was suppressed by the consumption of TPs. This trend was independent of the melanin index and the skin type, which indicates the ability of the skin to tan after sun exposure. Consumption of coffee, the largest source of TPs, suppressed the PS score (p<0.001). Consumption of green tea, the second largest source of TPs, also suppressed the PS score, which was weaker than coffee but was statistically significant (p=0.029). The PS score was suppressed the most in subjects with both a high consumption of coffee and green tea. Conclusion: Higher consumption of TPs may be beneficial to alleviate photoaging of the skin, and coffee as well as green tea contribute to suppress skin hyperpigmentation through adding large amounts of TPs in the diet.

The intake of polyphenols among Japanese has been estimated in several adult populations, but there has been no information regarding their intake among young adults, especially in those in their twenties. We conducted a food frequency questionnaire (FFQ)-based dietary assessment four times a year (once in each season) among Japanese university students and evaluated the total polyphenol intake across and within seasons. Forty-nine subjects (aged 20.7±0.6 y) completed our FFQ regarding polyphenol intake in February, May, August, and November 2016. We then calculated their total polyphenol intake using our polyphenol content database. The mean intake of total polyphenol across the seasons was 567±236 mg/d, which was largely sourced from beverages (62%). No significant differences were found in the total polyphenol intake or polyphenol intake from beverages among the four seasons. By contrast, we observed significant seasonal differences in the subjects' polyphenol intake from food; the polyphenol intake from food in February (255 mg/d) was significantly higher than that in May (215 mg/d), August (187 mg/d) and November (196 mg/d) (p<0.0001). These findings should assist in future estimations of dietary polyphenol intakes that consider differences according to age and season.