Identification of sika deer and red deer using partial cytochrome b and 12s ribosomal RNA genes

A study was conducted on the identifications of the degraded samples of sika deer （Cervus nippon） and red deer （Cervus elaphus） by phylogenetic and nucleotide distance analysis of partial Cytb and 12s rRNA genes sequences. 402 bp Cytb genes were achieved by PCR-sequencing using DNA extracted from 8 case samples, and contrasted with 27 sequences of Cytb gene downloaded from GenBank database. The values of three nucleotide distance between three suspected samples and sika deer were identical （0.026±0.006）, which was smaller than the smallest nucleotide distance between eastern red deer and sika deer （0.036）. Furthermore, phylogenetic analysis of sika deer and red deer indicated that the evidences located within the same cluster as sika deer. The evidences were sika deer materials. As the same way, other three suspected samples were derived from red deer. The results were further confirmed by phylogenetic and nucleotide distance analysis of 387 bp 12s rRNA gene. The method was powerful and less time-consuming and helpful to reduce the related cases with wildlife.

Phylogenetic Relationships among 12 Species of Tetrigidae (Orthoptera:Tetrigoidea) Based on Partial Sequences of 12S and 16S Ribosomal RNA

Mitochondrial 12S and 16S ribosomal RNA genes sequences were sequenced using dye-labeled terminator on an ABI 377 automated sequencer in 11 individuals and 1 species' sequences were gained from GenBank,representing 6 genera of family Tetrigidae.The collated sequences were aligned using Clustal X version 1.81 and then,the sequence variability and heredity distances based on Kimura 2-parameter model were calculated using Mega 2.1.In obtained sequences (736 bp),the average A+T content is 73.9%,ranging from 71.2% to 77.5%;the overall G+C content is 26.1%,ranging from 22.5% to 28.8%.Based on alignment of the combined sequences,185 parsimony-informative sites were revealed in 755 available base pairs.Phylogenetic trees were reconstructed using NJ,MP and ML methods with Cylindraustralia kochii as outgroup.The results indicated that the monophyletic nature of Tetrix is questioned and suggest that T.tubercarina may be given tribal rank.Our results also show that Coptltettix huanjiangensis and C.gongshanensis are the same species,i.e.Coptltettix gongshanensis Zheng,and C.huanjiangensis is the synonyms of C.gongshanensis.

Frequency of mitochondrial 12S rRNA gene A1555G and 961 insC mutations among children with sensorineural deafness in China

Objective： To investigate the frequency of mitochondrial 12S rRNA gene A1555G and 961 insC mutations among Chinese with sensorineural deafness. Methods： Blood samples from 78 sporadic cases with sensorineural deafness were obtained and DNA was extracted from the leukocytes, then the mitochondrial DNA target fragments were amplified by polymerase chain reaction（PCR）. The 1555G mutations were detected by BsmA 1 restriction endonuclease digestion, every fragment was analyzed by sequencing; All the 961 insC mutation were detected by direct sequencing. Results： The percent age of A1555G mutation and mt961C insertion were 6.4% and 2.6% in the hearing-impaired Chinese subjects respectively. Conclusion： A1555G and 961insC mutations in mitochondrial DNA 12S rRNA gene regions may play a role in the pathogenesis of hearing loss in the sporadic cases.

Species authentication of commercial beef jerky based on PCR-RFLP analysis of the mitochondrial 12S rRNA gene

In this study, we determined species-specific variations by analyzing the mitochondrial 12S rRNA gene sequence variation （-440 bp） in 17 newly obtained sequences and 90 published cattle, yak, buffalo, goat, and pig sequences, which represent 62 breeds and 17 geo- graphic regions. Based on the defined species-specific variations, two endonucleases, Alu I and Bfa I, were selected for species authentication using raw meat/tissue samples and the PCR-RFLP method. Goat and pig were identified using the Alu I enzyme, while cattle, yak, and buffalo were identified by digestion with Bfa I. Our approach had relatively high detection sensitivity of cattle DNA in mixed cattle and yak products, with the lowest detectable threshold equaling 20% of cattle DNA in a mixed cattle/yak sample. This method was successfully used to type commercial beef jerky products, which were produced by different companies utilizing various processing technologies. Our results show that several yak jerky products might be implicated in commercial fraud by using cattle meat instead of yak meat.

Advances in cochlear implantation for hereditary deafness caused by common mutations in deafness genes

The pathogenic factors of deafness are complex;more than 50%of cases are caused by genetic factors.Between 75%and 80%of cases of hereditary hearing impairment are autosomal recessive,15%to 25%are autosomal dominant,and 1%to 2%are mitochondrial or X-linked.Cochlea implantation is the main method for treating severe and extremely severe bilateral sensorineural deafness and it is widely used in clinical treatment.As clinical cases of cochlea implantation accumulate,differences in the efficacy of implantation in individuals are emerging and attracting attention.In addition to residual hearing level,implantation age,and other factors,gene mutation is an important factor influencing postoperative rehabilitation in patients.With continuous progress in genetic testing technology for deafness,genetic diagnosis has become an important tool in preoperative evaluation and postoperative effect prediction in patients undergoing cochlear implantation.This article reviews the current status and future development of cochlear implantation in the treatment of hereditary deafness resulting from mutations in common deafness-causing genes.

RIBOSOMAL PROTEIN S12 GENE MUTATION AFFECTING THE EXPRESSION OF BACTERIOPHAGE LAMBDA N GENE

Previous results in this laboratory indicated that in ribosomal protein S12 strepto-mycin-dependent mutants of Bacillus subtilis, the burst size of bacteriophage φ105 was decreased, and the protein synthesis was inhibited, while the DNA and