A highly efficient scheme for library preparation from single-stranded DNA.

Although methods for sequencing library preparation from double-stranded DNA are well established, those from single-stranded DNA (ssDNA) have not been well studied. Further, the existing methods have limitations in efficiency and yield. Therefore, we developed a highly efficient procedure for sequencing library preparation from ssDNA. In this method, the first adaptor tagging of ssDNA is performed using terminal deoxyribonucleotidyl transferase (TdT)-assisted adenylate connector-mediated ssDNA (TACS) ligation, which we reported recently. After complementary strand synthesis using the adaptor-tagged ssDNA, second adaptor tagging via Vaccinia virus topoisomerase I (VTopoI or TOPO)-based adaptor ligation is performed. With additional steps for degradation, repression, and removal of the adaptor dimer, the proposed TACS-TOPO scheme realizes adaptor dimer-free sequencing library preparation from ssDNA samples of 24 pg. The TACS-TOPO scheme was successfully applied to cell-free DNA analysis with amplification-free library preparation from 50 µL of human serum. A modified TACS-TOPO scheme was also applied to DNA extracted from ancient human bones, bringing two to eight times more library yields than those using a conventional library preparation protocol. The procedures for preparing VTopoI and its complex with a double-stranded oligonucleotide adaptor are also described. Overall, the proposed TACS-TOPO scheme can facilitate practical and sensitive sequencing analysis of ssDNA.

Three Autopsy Cases of Non-Meningococcal Waterhouse-Friderichsen Syndrome with Hypoplastic Spleen or Post-Splenectomy Status.

We report three cases of Waterhouse-Friderichsen syndrome (WFS) that were confirmed during forensic autopsies. Case 1 involved a man in his 50s post-splenectomy. Bacteriological examination revealed Streptococcus pneumoniae (S. pneumonia). The patient was considered to have died of asphyxiation after aspirating vomit. Case 2 involved a man in his 40s. Bacteriological examination again revealed S. pneumoniae. Histopathological examination showed hypoplasia of the spleen. This patient was considered to have died of multiple-organ failure due to sepsis, disseminated intravascular coagulation, and WFS. Case 3 involved a post-splenectomy woman in her 60s with a history of systemic lupus erythematosus. Bacteriological examination revealed Streptococcus oralis. This patient was considered to have died of multiple-organ failure due to sepsis, disseminated intravascular coagulation, and WFS. These three cases were included among forensic autopsies conducted in the last 5 years. WFS has been considered a rare disease, but may be more frequent than previously assumed. If a mildly ill patient displays a sudden change in status and dies within a short period of time, we consider it necessary to perform not only bacteriological examinations, but also histopathological examination of the spleen during autopsy.

Pamphilius japonicus feeds on Cornus: the first Old World record of Pamphiliidae (Hymenoptera) associated with Cornaceae.

We identified newly discovered pamphiliid larvae feeding on Cornus in Tochigi and Ibaraki Prefectures, Honshu, Japan, with Pamphilius japonicus Shinohara, 1985, by molecular methods using mitochondrial cytochrome oxidase subunit 1 (COI) gene sequences. The host plant of P. japonicus was unknown. This is the first record of the Cornaceae as a host plant of the Pamphiliidae in the Old World. The larvae were solitary leaf-rollers on Cornus and discovered mainly on small young trees in shadowy forests.

Cranio-morphometric and aDNA corroboration of the Austronesian dispersal model in ancient Island Southeast Asia: Support from Gua Harimau, Indonesia.

The Austronesian language is spread from Madagascar in the west, Island Southeast Asia (ISEA) in the east (e.g. the Philippines and Indonesian archipelagoes) and throughout the Pacific, as far east as Easter Island. While it seems clear that the remote ancestors of Austronesian speakers originated in Southern China, and migrated to Taiwan with the development of rice farming by c. 5500 BP and onto the northern Philippines by c. 4000 BP (the Austronesian Dispersal Hypothesis or ADH), we know very little about the origins and emergence of Austronesian speakers in the Indonesian Archipelago. Using a combination of cranial morphometric and ancient mtDNA analyses on a new dataset from Gua Hairmau, that spans the pre-Neolithic through to Metal Period (5712-5591cal BP to 1864-1719 cal BP), we rigorously test the validity of the ADH in ISEA. A morphometric analysis of 23 adult male crania, using 16 of Martin's standard measurements, was carried out with results compared to an East and Southeast Asian dataset of 30 sample populations spanning the Late Pleistocene through to Metal Period, in addition to 39 modern samples from East and Southeast Asia, near Oceania and Australia. Further, 20 samples were analyzed for ancient mtDNA and assigned to identified haplogroups. We demonstrate that the archaeological human remains from Gua Harimau cave, Sumatra, Indonesia provide clear evidence for at least two (cranio-morphometrically defined) and perhaps even three (in the context of the ancient mtDNA results) distinct populations from two separate time periods. The results of these analyses provide substantive support for the ADH model in explaining the origins and population history of ISEA peoples.

DNA Barcodes Identify the Larvae and Unassociated Male of Three Onycholyda Sawflies (Hymenoptera, Pamphiliidae) from China.

A molecular analysis based on mitochondrial cytochrome oxidase subunit 1 (COI) gene sequences has indicated that larvae collected in Sichuan and Zhejiang Provinces, China, belong to Onycholyda xanthogaster Shinohara, 1999, and O. fulvicornis Shinohara, in Shinohara Wei, 2016 (Hymenoptera, Pamphiliidae), and that a male Onycholyda specimen from Mt. Tianmushan, Zhejiang Province is the hitherto unknown male of O. tianmushana Shinohara Xiao, 2006. The first host plant records are Rubus inopertus (Focke) Focke (Rosaceae) for O. xanthogaster and Rubus hirsutus Thunb. for O. fulvicornis. The larvae of O. xanthogaster and O. fulvicornis are briefly described and O. xanthogaster is newly recorded from Sichuan Province. The male of O. tianmushana is described for the first time.

Ethnic derivation of the Ainu inferred from ancient mitochondrial DNA data.

OBJECTIVES: The Ainu, the indigenous people living on the northernmost island of Japan, Hokkaido, have long been a focus of anthropological interest because of their cultural, linguistic, and physical identity. A major problem with genetic studies on the Ainu is that the previously published data stemmed almost exclusively from only 51 modern-day individuals living in Biratori Town, central Hokkaido. To clarify the actual genetic characteristics of the Ainu, individuals who are less influenced by mainland Japanese, who started large-scale immigration into Hokkaido about 150 years ago, should be examined. Moreover, the samples should be collected from all over Hokkaido. MATERIALS AND METHODS: Mitochondrial DNA haplogroups of 94 Ainu individuals from the Edo era were successfully determined by analyzing haplogroup-defining polymorphisms in the hypervariable and coding regions. Thereafter, their frequencies were compared to those of other populations. RESULTS: Our findings indicate that the Ainu still retain the matrilineage of the Hokkaido Jomon people. However, the Siberian influence on this population is far greater than previously recognized. Moreover, the influence of mainland Japanese is evident, especially in the southwestern part of Hokkaido that is adjacent to Honshu, the main island of Japan. DISCUSSION: Our results suggest that the Ainu were formed from the Hokkaido Jomon people, but subsequently underwent considerable admixture with adjacent populations. The present study strongly recommends revision of the widely accepted dual-structure model for the population history of the Japanese, in which the Ainu are assumed to be the direct descendants of the Jomon people.

Pamphilius ishikawai feeds on Astilbe: the first record of Pamphiliidae (Hymenoptera) associated with Saxifragaceae.

Based on field observations and rearing experiments in Nagano and Tochigi prefectures in central Honshu, Japan, host plants and life history of a leaf-rolling sawfly, Pamphilius ishikawai Shinohara, 1979, are recorded for the first time. The larva is a solitary leaf-roller on Astilbe. This is the first record of the Saxifragaceae as a host plant of the Pamphiliidae. We made molecular phylogenetic analysis using mitochondrial cytochrome oxidase subunit 1 (COI) gene sequences for nine individuals of P. ishikawai feeding on three different species of Astilbe in two localities with different climates and for six outgroup pamphiliine species. It revealed very small genetic variability within P. ishikawai and suggested probable monophyly of the P. sulphureipes group.

Multiplex APLP System for High-Resolution Haplogrouping of Extremely Degraded East-Asian Mitochondrial DNAs.

Mitochondrial DNA (mtDNA) serves as a powerful tool for exploring matrilineal phylogeographic ancestry, as well as for analyzing highly degraded samples, because of its polymorphic nature and high copy numbers per cell. The recent advent of complete mitochondrial genome sequencing has led to improved techniques for phylogenetic analyses based on mtDNA, and many multiplex genotyping methods have been developed for the hierarchical analysis of phylogenetically important mutations. However, few high-resolution multiplex genotyping systems for analyzing East-Asian mtDNA can be applied to extremely degraded samples. Here, we present a multiplex system for analyzing mitochondrial single nucleotide polymorphisms (mtSNPs), which relies on a novel amplified product-length polymorphisms (APLP) method that uses inosine-flapped primers and is specifically designed for the detailed haplogrouping of extremely degraded East-Asian mtDNAs. We used fourteen 6-plex polymerase chain reactions (PCRs) and subsequent electrophoresis to examine 81 haplogroup-defining SNPs and 3 insertion/deletion sites, and we were able to securely assign the studied mtDNAs to relevant haplogroups. Our system requires only 1×10-13 g (100 fg) of crude DNA to obtain a full profile. Owing to its small amplicon size (<110 bp), this new APLP system was successfully applied to extremely degraded samples for which direct sequencing of hypervariable segments using mini-primer sets was unsuccessful, and proved to be more robust than conventional APLP analysis. Thus, our new APLP system is effective for retrieving reliable data from extremely degraded East-Asian mtDNAs.

A Unique Primer with an Inosine Chain at the 5'-Terminus Improves the Reliability of SNP Analysis Using the PCR-Amplified Product Length Polymorphism Method.

Polymerase chain reaction-amplified product length polymorphism (PCR-APLP) is one of the most convenient and reliable methods for single nucleotide polymorphism (SNP) analysis. This method is based on PCR, but uses allele-specific primers containing SNP sites at the 3'-terminus of each primer. To use this method at least two allele-specific primers and one "counter-primer", which serves as a common forward or reverse primer of the allele-specific primers, are required. The allele-specific primers have SNP sites at the 3'-terminus, and another primer should have a few non-complementary flaps at the 5'-terminus to detect SNPs by determining the difference of amplicon length by PCR and subsequent electrophoresis. A major disadvantage of the addition of a non-complementary flap is the non-specific annealing of the primer with non-complementary flaps. However, a design principle for avoiding this undesired annealing has not been fully established, therefore, it is often difficult to design effective APLP primers. Here, we report allele-specific primers with an inosine chain at the 5'-terminus for PCR-APLP analysis. This unique design improves the competitiveness of allele-specific primers and the reliability of SNP analysis when using the PCR-APLP method.