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The mechanism of free radical production by complex I deficiency is ill-defined, although it is of significant contemporary interest. This study studied the ROS production and antioxidant defenses in children with mitochondrial NADH dehydrogenase deficiency. ROS production has remained significantly elevated in patients compared to controls. The expression of all antioxidant enzymes significantly increased at mRNA level. However, the enzyme activities did not correlate with high mRNA or protein expression. Only the activity of superoxide dismutase (SOD) was found to correlate with higher mRNA expression in patient derived cell lines. The activities of the enzymes such as glutathione peroxidase (GPx), Catalase (CAT) and glutathione-S-transferase (GST) were significantly reduced in patients (p

The parsimony and bootstrap branching pattern of major groups of land plants derived from relevant 5S rRNA sequence trees have been discussed in the light of paleobotanical and morphological evidences. Although 5S rRNA sequence information is not useful for dileneating angiosperm relationships, it does capture the earlier phase of land plant evolution. The consensus branching pattern indicates an ancient split of bryophytes and vascular plants from the charophycean algal stem. Among the bryophytes,Marchantia andLophocolea appear to be phylogenetically close and together withPlagiomnium form a monophyletic group.Lycopodium andPsilotum arose early in vascular land plant evolution, independent of fem-sphenopsid branch. Gymnosperms are polyphyletic; conifers, Gnetales and cycads emerge in that order with ginkgo joiningCycas. Among the conifers,Metasequoia,Juniperus andTaxus emerge as a branch independent ofPinus which joins Gnetales.

Based on morphological, palaeoanthropological and molecular biological studies, human evolution from the Miocene to the Present has been reviewed. The initial divergence of orangutan from the hominoid stock, the divergence of man from the last common ancestor with the African apes, the origin and expansion ofHomo lineage and the advent of modern man have been discussed.

Background Mitochondrial encephalomyopathies are a heterogeneous group of clinical disorders generally caused due to mutations in either mitochondrial DNA (mtDNA) or nuclear genes encoding oxidative phosphorylation (OXPHOS). We analyzed the mtDNA sequences from a group of 23 pediatric patients with clinical and morphological features of mitochondrial encephalopathies and tried to establish a relationship of identified variants with the disease. Methodology/Principle Findings Complete mitochondrial genomes were amplified by PCR and sequenced by automated DNA sequencing. Sequencing data was analyzed by SeqScape software and also confirmed by BLASTn program. Nucleotide sequences were compared with the revised Cambridge reference sequence (CRS) and sequences present in mitochondrial databases. The data obtained shows that a number of known and novel mtDNA variants were associated with the disease. Most of the non-synonymous variants were heteroplasmic (A4136G, A9194G and T11916A) suggesting their possibility of being pathogenic in nature. Some of the missense variants although homoplasmic were showing changes in highly conserved amino acids (T3394C, T3866C, and G9804A) and were previously identified with diseased conditions. Similarly, two other variants found in tRNA genes (G5783A and C8309T) could alter the secondary structure of Cys-tRNA and Lys-tRNA. Most of the variants occurred in single cases; however, a few occurred in more than one case (e.g. G5783A and A10149T). Conclusions and Significance The mtDNA variants identified in this study could be the possible cause of mitochondrial encephalomyopathies with childhood onset in the patient group. Our study further strengthens the pathogenic score of known variants previously reported as provisionally pathogenic in mitochondrial diseases. The novel variants found in the present study can be potential candidates for further investigations to establish the relationship between their incidence and role in expressing the disease phenotype. This study will be useful in genetic diagnosis and counseling of mitochondrial diseases in India as well as worldwide.

The population of the Indian subcontinent represents a very complex social and cultural structure. Occupying a geographically central position for the early modern human migrations, indications are that the founder group that migrated out of East Africa also reached India. In the present study we used the twin strategy of mapping the whole mitochondrial DNA (mtDNA) using the standard 14 restriction enzymes, and sequencing the non-transcribed HVSI region, to derive maximum maternal lineages from a sample of non-tribal Indians. The essential features of the reduced median network of the two datasets were the same. Both showed two demographic expansions of two major haplogroups, 'M' and 'N'. The reduced median network was drawn with inputs from other studies on the Indian population, and correlated with data from other ethnic populations. The coalescence time of expansions and genetic diversity were estimated. A reduced median network was also drawn combining data from studies on Africans, Southeast Asians and West-Eurasians, tracing the migration of 'M' from East Africa to India. A time estimate of the migration of major mtDNA haplogroups from Africa was attempted. The comparison of a set of Indian maternal lineages belonging to different geographical regions of the country, with other populations revealed the in-situ differentiation and antiquity of the Indian population. Our analysis places the 'southern route' migration as the source of haplogroup 'M'. Multiple migrations might have brought the other major haplogroups, 'N' and 'R', found in our sample to India. Archaeological evidence of modern humans in the subcontinent supports this mtDNA study.

A best-fit α-globin phylogeny was identified by means of a global minimization approach from among the topologies generated by a parsimony strategy. Zip parsimony method was used to derive a set of near-parsimonious trees. For each of these topologies, a difference matrix was computed; and the topology with the best goodness of fit with the original matrix was retained as the best tree. Based on this phylogenetic scheme inter-relationships among eutherian orders and the evolutionary development of primates has been discussed.