SUMMARYGinseng (Panax ginseng) is a famous medicinal herb, but the composition and structure of its genome are largely unknown. Here we characterized the major repeat components and inspected their distribution in the ginseng genome. By analyzing three repeat-rich bacterial artificial chromosome (BAC) sequences from ginseng, we identified complex insertion patterns of 34 long terminal repeat retrotransposons (LTR-RTs) and 11 LTR-RT derivatives accounting for more than 80% of the BAC sequences. The LTR-RTs were classified into three Ty3/gypsy (PgDel, PgTat and PgAthila) and two Ty1/Copia (PgTork and PgOryco) families. Mapping of 30-Gbp Illumina whole-genome shotgun reads to the BAC sequences revealed that these five LTR-RT families occupy at least 34% of the ginseng genome. The Ty3/Gypsy families were predominant, comprising 74 and 33% of the BAC sequences and the genome, respectively. In particular, the PgDel family accounted for 29% of the genome and presumably played major roles in enlargement of the size of the ginseng genome. Fluorescence in situ hybridization (FISH) revealed that the PgDel1 elements are distributed throughout the chromosomes along dispersed heterochromatic regions except for ribosomal DNA blocks. The intensity of the PgDel2 FISH signals was biased toward 24 out of 48 chromosomes. Unique gene probes showed two pairs of signals with different locations, one pair in subtelomeric regions on PgDel2-rich chromosomes and the other in interstitial regions on PgDel2-poor chromosomes, demonstrating allotetraploidy in ginseng. Our findings promote understanding of the evolution of the ginseng genome and of that of related species in the Araliaceae.

SUMMARYAlthough plant genome sizes are extremely diverse, the mechanism underlying the expansion of huge genomes that did not experience whole-genome duplication has not been elucidated. The pepper, Capsicum annuum, is an excellent model for studies of genome expansion due to its large genome size (2700 Mb) and the absence of whole genome duplication. As most of the pepper genome structure has been identified as constitutive heterochromatin, we investigated the evolution of this region in detail. Our findings show that the constitutive heterochromatin in pepper was actively expanded 20.0-7.5 million years ago through a massive accumulation of single-type Ty3/Gypsy-like elements that belong to the Del subgroup. Interestingly, derivatives of the Del elements, such as non-autonomous long terminal repeat retrotransposons and longunit tandem repeats, played important roles in the expansion of constitutive heterochromatic regions. This expansion occurred not only in the existing heterochromatic regions but also into the euchromatic regions. Furthermore, our results revealed a repeat of unit length 18-24 kb. This repeat was found not only in the pepper genome but also in the other solanaceous species, such as potato and tomato. These results represent a characteristic mechanism for large genome evolution in plants.

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3′-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3′-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3′-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention.

PurposeThis study aimed to compare the efficacy of and patient satisfaction with the wide-awake local anesthesia with no tourniquet (WALANT) technique in open cubital and carpal tunnel release surgery.MethodsFrom January 2016 to February 2017, 20 cubital tunnel syndrome (CuTS) patients were in a wide-awake (WA) group and 22 in a general (GA) anesthesia group in . Also, 20 carpal tunnel syndrome (CTS) patients were in a WA group, 22 in a local anesthesia (LA) group, and 20 in a GA group. Injection pain, perioperative pain, and postoperative pain were assessed using a 10-point pain VAS. In CuTS, functional outcome on the “quick” Disabilities of the Arm, Shoulder, and Hand questionnaire were evaluated. In CTS, subjective outcomes were assessed using the Korean version of the Michigan Hand Outcomes Questionnaire.ResultsBoth CuTS and CTS showed significant postoperative pain reduction in group WA. In CuTS, group WA had less pain than group GA up to 48 hours after surgery (P<0.05). Supplemental opioid injections were used on hospitalization day by 12% of group WA and 35% of group GA. In CTS, the postoperative VAS scores in group WA were lower during the first 24 hours than groups LA and GA (P<0.05). Opioid injections were used on hospitalization day by 5% of WA, 18% of LA, and 32% of group GA. There was no difference in postoperative functional outcomes according to anesthesia method in CuTS or CTS.ConclusionCubital and carpal tunnel surgery using the WALANT technique was comparable in function to other anesthesia methods and superior for pain. Immediate postoperative pain was much lower than other groups, which could reduce the use of opioids during hospitalization.

Abstract. Aberrant methylation of promoter regions associated with gene silencing is one of the major mechanisms underlying the inactivation of tumor suppressor genes in carcinogenesis. Previous studies have proposed that methylated DNA from tumor cells is released into the circulation and might be widely used as a marker for non-invasive tumor detection. Catalytic activities of folate metabolismrelated enzymes and adequate synthesis of methyl donors are important elements for the cellular methylation reaction. In the present study, we sought to determine the following: i) genotype frequencies of MTHFR and MTR involved in folate metabolism in cases and cancer-free controls; and ii) the methylation status of three candidate genes (p16 INK4A , p73 and hMLH1) in plasma related to the folate and homocysteine levels. From genotype frequency analysis, individuals homozygous for the MTHFR 677TT genotype had a significantly reduced risk of developing colorectal cancer compared with those harboring the MTHFR 677CC genotype (OR, 0.206; 95% CI, 0.070-0.604; P=0.005), and had a lower plasma folate concentration than those with the MTHFR 677CC+CT genotype (P<0.05). Using methylation-specific PCR, p73 was shown to be more frequently methylated in the high folate group [50% (8 of 16)] than in the medium [16.7% (3 of 18)] or low folate subgroups [11.1% (2 of 18)].In conclusion, subjects with the variant MTHFR 677TT genotype appeared to have a significantly lower risk for colorectal cancer than those with the MTHFR 677CC genotype, and the methylation status of circulating p73 genomic DNA was substantially altered by the plasma folate level.