RESUMO
DNA barcodes are very useful for species identification especially when identification by traditional morphological characters is difficult. However, the short mitochondrial and chloroplast barcodes currently in use often fail to distinguish between closely related species, are prone to lateral transfer, and provide inadequate phylogenetic resolution, particularly at deeper nodes. The deficiencies of short barcode identifiers are similar to the deficiencies of the short year identifiers that caused the Y2K problem in computer science. The resolution of the Y2K problem was to increase the size of the year identifiers. The performance of conventional mitochondrial COI barcodes for phylogenetics was compared with the performance of complete mitochondrial genomes and nuclear ribosomal RNA repeats obtained by genome skimming for a set of caddisfly taxa (Insect Order Trichoptera). The analysis focused on Trichoptera Family Hydropsychidae, the net-spinning caddisflies, which demonstrates many of the frustrating limitations of current barcodes. To conduct phylogenetic comparisons, complete mitochondrial genomes (15 kb each) and nuclear ribosomal repeats (9 kb each) from six caddisfly species were sequenced, assembled, and are reported for the first time. These sequences were analyzed in comparison with eight previously published trichopteran mitochondrial genomes and two triochopteran rRNA repeats, plus outgroup sequences from sister clade Lepidoptera (butterflies and moths). COI trees were not well-resolved, had low bootstrap support, and differed in topology from prior phylogenetic analyses of the Trichoptera. Phylogenetic trees based on mitochondrial genomes or rRNA repeats were well-resolved with high bootstrap support and were largely congruent with each other. Because they are easily sequenced by genome skimming, provide robust phylogenetic resolution at various phylogenetic depths, can better distinguish between closely related species, and (in the case of mitochondrial genomes), are backwards compatible with existing mitochondrial barcodes, it is proposed that mitochondrial genomes and rRNA repeats be used as next generation DNA barcodes.
RESUMO
BACKGROUND: Since 1997, the annual case occurrence of vivax malaria in the Republic of Korea have exceeded 1,000 cases since 1997. The military is thought to be an important source of the current outbreak. We collected various informations about malaria cases (soldiers, veterans and civilians) which occurred in 2000, and analyzed the characteristics of the current outbreak. METHODS: Informations about malaria cases of soldiers, veterans and civilians, including name, age, sex, day of onset, region, etc., were collected through the National Institute of Health. RESULTS: Out of total 4,141 cases, 1,288 (31.1%) occurred in the military, 1,273 (30.7%) occurred among the veterans, and 1,580 (38.2%) occurred among civilians. The monthly case occurrence reached its peak in early August. Areas such as Cheolwon, Yeoncheon and Paju showed the highest prevalence. CONCLUSION: It is considered that the current malaria outbreak has escaped from the exponential growth phase, however, more attention should be paid to prevent further spreading of malaria infection.
