Schizothorax argentatus that only distributes in the Ili River basin in Xinjiang is one of the rare and endangered species of schizothorax in China, thus has high scientific and economic values. In this study, the complete mitochondrial genome sequence of S. argenteus with a length of 16 580 bp was obtained by high-throughput sequencing. The gene compositions and arrangement were similar to those of typical vertebrates. It contained 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding region (D-loop). The nucleotide compositions were A (30.25%), G (17.28%), C (27.20%), and T (25.27%), respectively, showing obvious AT bias and anti-G bias. Among the tRNA genes, only tRNA-Ser^(GCU) could not form a typical cloverleaf structure due to the lack of dihydrouracil arm. The AT-skew and GC-skew values of the ND6 gene were fluctuating the most, suggesting that the gene may experience different selection and mutation pressures from other genes. The mitochondrial control region of S. argenteus contained three different domains, i.e., termination sequence region (ETAS), central conserved region (CSB-F, CSB-E, CSB-D, and CSB-B), and conserved sequence region (CSB1, CSB2, and CSB3). The conserved sequence fragment TT (AT) nGTG, which was ubiquitous in Cypriniformes, was identified at about 50 bp downstream CSB3. Phylogenetic relationships based on the complete mitochondrial genome sequence of 28 Schizothorax species showed that S. argenteus had differentiated earlier and had a distant relationship with other species, which may be closely related to the geographical location and the hydrological environment where it lives.
Animals ; Genome, Mitochondrial/genetics* ; Phylogeny ; Sequence Analysis, DNA ; Cyprinidae/genetics* ; RNA, Transfer/genetics* ; DNA, Mitochondrial/genetics* ; Genes, Mitochondrial

Objective To study the heteroplasmy of the whole mitochondrial genome genotyping result of hair shaft samples using HID Ion GeneStudio^TM S5 Sequencing System. Methods The buccal swabs and blood of 8 unrelated individuals, and hair shaft samples from different parts of the same individual were collected. Amplification of whole mitochondrial genome was performed using Precision ID mtDNA Whole Genome Panel. Analysis and detection of whole mitochondrial genome were carried out using the HID Ion GeneStudio^TM S5 Sequencing System. Results The mitochondrial DNA sequences in temporal hair shaft samples from 2 individuals showed heteroplasmy, while whole mitochondrial genome genotyping results of buccal swabs, blood, and hair samples from the other 6 unrelated individuals were consistent. A total of 119 base variations were observed from the 8 unrelated individuals. The numbers of variable sites of the individuals were 29, 40, 38, 35, 13, 36, 40 and 35, respectively. Conclusion Sequence polymorphism can be fully understood using HID Ion GeneStudio^TM S5 Sequencing system.
DNA, Mitochondrial/genetics* ; Genome, Mitochondrial/genetics* ; Heteroplasmy ; High-Throughput Nucleotide Sequencing ; Humans ; Sequence Analysis, DNA

As conserved enzymes with important functions, aminoacyl-tRNA synthetase are expressed ubiquitously in cells. These include cytoplasmic aminoacyl-tRNA synthetase, mitochondrial aminoacyl-tRNA synthetase and bifunctional aminoacyl-tRNA synthetase. Mitochondrial aminoacyl-tRNA synthetases catalyze the binding of amino acids with its corresponding tRNA in the mitochondria and participate in the translation of 13 subunits of oxidative phosphorylation enzyme complexes encoded by the mitochondrial genome. Mutations in genes encoding mitochondrial aminoacyl-tRNA synthase may cause a variety of genetic disorders. This review has summarized the clinical characteristics, molecular pathogenesis and treatment of genetic diseases caused by mutations of such genes.
Humans ; RNA, Transfer, Amino Acyl ; Genes, Mitochondrial ; Amino Acyl-tRNA Synthetases/genetics* ; Genome, Mitochondrial ; Mitochondria/genetics*

Nuclease-based gene editing technologies have opened up opportunities for correcting human genetic diseases. For the first time, scientists achieved targeted gene editing of mitochondrial DNA in mouse oocytes fused with patient cells. This fascinating progression may encourage the development of novel therapy for human maternally inherent mitochondrial diseases.
Animals ; DNA, Mitochondrial ; genetics ; Embryo, Mammalian ; metabolism ; Genome ; Germ Cells ; metabolism ; Humans ; Mitochondrial Diseases ; genetics ; therapy ; RNA Editing ; genetics

OBJECTIVETo construct the haplogroup and perform an analysis of mitochondrial whole-genome sequence in Tibetan and Han Chinese. Variations of nucleotide of mitochondrial DNA (mtDNA) were identified and compared between the Tibetan and Han population.

METHODSThe mtDNA whole sequences of 40 Tibetan and 50 Han individuals were sequenced by an Applied Biosystems 3730 DNA automatic sequencer. The sequences were assembled using software phredPhrap16.0, and all assembled sequences were manually verified according to the criterion of rCRS (revised Cambridge Reference Sequence). The haplogroups of mtDNA were constructed using phylogenetic analysis according to the criteria of MITOMAP by Network method. The data were elucidated by integrated methods.

RESULTSAuthors' results showed that all the pooled 90 subjects belonged to the Macrohaplogroup M and N, and were classified into 13 haplogroups. No differences were observed among the haplogroups of the two populations except for M9 haplogroup. A total of 21 variants were detected by comparing the mtDNA whole sequences between Tibetan and Han population; of those, 5 variants have not been reported before. In addition, we constructed the haplotypes of 5 variants harboring the D-loop region, and founded prominent difference in both supertype 1 and supertype 2 between Tibetan and Han population.

CONCLUSIONThe phylogenetic analysis indicates that the Tibetan and Han ethnic groups shared close maternal relationship in origin. The biological implication of the significant variants is worth elucidating; whether they are the results of adaptive selection or neutral selection or pathological variations need to be further studied.

Asian Continental Ancestry Group ; genetics ; China ; ethnology ; DNA, Mitochondrial ; analysis ; Ethnic Groups ; genetics ; Evolution, Molecular ; Genetics, Population ; Genome, Mitochondrial ; genetics ; Haplotypes ; genetics ; Humans ; Tibet ; ethnology

Leber's hereditary optic neuropathy (LHON) is a maternally inherited disorder leading to rapid, painless, bilateral and usually permanent central vision loss in young adults, males are preferentially affected. The maternal transmission of this visual dysfunction in LHON families suggested that mutations in the mitochondrial DNA (mtDNA) are the molecular bases of the disorder. The ND1 G3460A, ND4 G11778A and ND6 T14484C mutations in the genes encoding the subunits of respiratory chain complex I, account for more than 50% of LHON families worldwide. These three mutations are designated to be primary mutations because they impart a high risk for LHON expression. However, matrilineal relatives within and among families, despite carrying the same LHON-associated mtDNA mutation(s), exhibit a wide range of onset, severity, and the progression of visual impairment. These findings strongly indicated that the LHON-associated primary mutation(s) are the primary factors underlying the development of vision loss, but they themselves are insufficient to produce a clinic phenotype. The prone to male, incomplete penetrance, and phenotypic variability of vision loss suggest that other modifier factors including personal factors, environmental factors, nuclear modifier genes and mitochondrial haplotypes contribute to the phenotypic expression of these mtDNA mutations. In particular, the mitochondrial haplotypes may play a synergic role in the development of vision loss in the families carrying the LHON-associated primary mtDNA mutation(s).
DNA, Mitochondrial ; genetics ; Genome, Human ; genetics ; Genomics ; Haplotypes ; Humans ; Mitochondria ; genetics ; Optic Atrophy, Hereditary, Leber ; genetics ; pathology

OBJECTIVETo investigate the association of the mitochondrial DNA region np16181-16193 variations with type 2 diabetes mellitus (T2DM).

METHODSBlood samples of 199 unrelated T2DM patients and 205 normal controls were collected to detect the mitochondrial DNA region np16181-16193 variations by PCR and sequencing, and to analyze the association of the variations with the major clinical symptoms.

RESULTSThe mitochondrial DNA np16181-16193 region is a hypervariable area, with several polymorphisms. Four types of np16181-16193 region variations were found only in T2DM. The 1-hour postprandial blood glucose (P1BG) in the T2DM individuals with np16181-16193 region variations was significantly higher than those without variations (P<0.05), while there was no significant difference in other biochemical parameters (P>0.05).

CONCLUSIONThe mitochondrial DNA np16181-16193 variations could not be regarded as a risk factor for T2DM.

Adult ; Complementarity Determining Regions ; genetics ; DNA Mutational Analysis ; DNA, Mitochondrial ; analysis ; Diabetes Mellitus, Type 2 ; genetics ; Female ; Genetic Predisposition to Disease ; Genome, Mitochondrial ; genetics ; Humans ; Male ; Sequence Analysis, DNA

OBJECTIVETo ascertain whether other variations coexist with 1555(A--> G) mutation in the mitochondrial DNA and may aggravate the severity of hearing loss or increase the penetrance of 1555(A--> G) mutation in a large family with maternally inherited nonsyndromic deafness in Huaiyin, Jiangsu province.

METHODSPCR-restriction fragment length polymorphism (PCR-RFLP) was used to screen both the nt1555 and the nt7445 of the mitochondrial DNA from 27 maternal members in the core family; and then the mitochondrial genomes from two maternal members, and the 12S rRNA genes MTRNR1 and tRNA-Ser(UCN) gene MTTS1 from the others, were amplified by PCR-RFLP and were sequenced.

RESULTS1555(A--> G) mutation in the mitochondrial DNA was reverified to be one of the major factors which cause maternally inherited nonsyndromic deafness and the cosegregation of 955-960(insC) and 1555(A--> G) was present in this family. Moreover, 7449 (insG), a novel homoplasmic mutation in the tRNA-Ser(UCN) gene, was found to co-exist with 1555(A--> G) mutation in two maternal members.

CONCLUSIONThe cosegregation of 955-960(insC) and 1555(A--> G) implies that 955-960(insC) may synergistically cause hearing loss in the presence of an 1555(A--> G) mutation, serving as an aggravating factor to enhance the sensitivity to aminoglycosides, and may sometimes increase the penetrance of 1555(A--> G) mutation.

DNA, Mitochondrial ; chemistry ; genetics ; Deafness ; genetics ; Female ; Genetic Predisposition to Disease ; Genome, Mitochondrial ; genetics ; Humans ; Male ; Pedigree ; Point Mutation ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Sequence Analysis, DNA

Mitochondrial genomes have been extensively studied for phylogenetic purposes and to investigate intra- and interspecific genetic variations. In recent years, numerous groups have undertaken sequencing of platyhelminth mitochondrial genomes. Haplorchis taichui (family Heterophyidae) is a trematode that infects humans and animals mainly in Asia, including the Mekong River basin. We sequenced and determined the organization of the complete mitochondrial genome of H. taichui. The mitochondrial genome is 15,130 bp long, containing 12 protein-coding genes, 2 ribosomal RNAs (rRNAs, a small and a large subunit), and 22 transfer RNAs (tRNAs). Like other trematodes, it does not encode the atp8 gene. All genes are transcribed from the same strand. The ATG initiation codon is used for 9 protein-coding genes, and GTG for the remaining 3 (nad1, nad4, and nad5). The mitochondrial genome of H. taichui has a single long non-coding region between trnE and trnG. H. taichui has evolved as being more closely related to Opisthorchiidae than other trematode groups with maximal support in the phylogenetic analysis. Our results could provide a resource for the comparative mitochondrial genome analysis of trematodes, and may yield genetic markers for molecular epidemiological investigations into intestinal flukes.
Animals ; Asia ; Codon, Initiator ; DNA, Mitochondrial/chemistry/genetics ; Gene Order ; Genes, Helminth ; *Genome, Mitochondrial ; Heterophyidae/*genetics/isolation & purification ; Humans ; Molecular Sequence Data ; Sequence Analysis, DNA

Mitochondrial genome sequence of malaria parasites has served as a potential marker for inferring evolutionary history of the Plasmodium genus. In Plasmodium falciparum, the mitochondrial genome sequences from around the globe have provided important evolutionary understanding, but no Indian sequence has yet been utilized. We have sequenced the whole mitochondrial genome of a single P. falciparum field isolate from India using novel primers and compared with the 3D7 reference sequence and 1 previously reported Indian sequence. While the 2 Indian sequences were highly divergent from each other, the presently sequenced isolate was highly similar to the reference 3D7 strain.
DNA, Mitochondrial/*chemistry/*genetics ; Genetic Variation ; *Genome, Mitochondrial ; Humans ; India ; Malaria, Falciparum/parasitology ; Molecular Sequence Data ; Plasmodium falciparum/*genetics/isolation & purification ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid