Joykrushna Jena

Genetic differentiation in Indian Major Carp, Cirrhinus mrigala (Hamilton, 1822) from Indian Rivers, as revealed by direct sequencing analysis of mitochondrial Cytochrome b region

Abstract A 307 bp segment of Cytochrome b gene of mtDNA was sequenced and analyzed for 90 individuals of Cirrhinus mrigala collected across the three rivers, namely Ganges, Narmada and Brahmaputra. Analyses revealed the presence of 14 haplotypes with haplotype diversity (h) ranging from 0.304 to 0.692, and nucleotide diversity (π) 0.002–0.043. The majority of variation was found within the population (96.21%), and the FST value (0.035) as well as the value of exact test of population differentiation (0.893) were found to be insignificant (p < 0.05). Analysis of molecular variance (AMOVA) also indicated insignificant differentiation among sub-populations. Generally, low genetic differences were observed even though those populations were from different geographic locations. The present study suggests a single panmictic population of C. mrigala across the three rivers of India.

Population divergence and structure of Cirrhinus mrigala from peninsular rivers of India, revealed by mitochondrial cytochrome b gene and truss morphometric analysis

Abstract Genetic diversity and population structure of Cirrhinus mrigala from peninsular riverine systems of India was studied using mitochondrial DNA gene, cytochrome b and truss morphometric analysis. Analysis of 982 bp of the cytochrome b gene from 182 samples collected from six rivers revealed the presence of 28 haplotypes with overall high haplotype diversity value of 0.78981 and nucleotide diversity value of 0.00215. Analysis of molecular variance (AMOVA) showed that genetic variation is mainly harbored within populations rather than among populations. The pairwise Fst values (−0.009 to 0.084) was indicative of a low genetic structure among mrigal populations. Morphometric examination of 243 samples using 10 truss landmarks and principal component analysis showed a similar trend when compared with genetic data. Overall, low genetic and morphometric differences were observed despite those populations from different geographic locations. The results of this study would provide essential information to resource recovery and help in delineating populations for fishery management. Besides, the data will provide a valuable baseline for further investigations on the geographic distribution of this commercially important fish species.

Assembly and variation analyses of Clarias batrachus mitogenome retrieved from WGS data and its phylogenetic relationship with other catfishes

Whole genome sequencing (WGS) using next generation sequencing technologies paves the way to sequence the mitochondrial genomes with greater ease and lesser time. Here, we used the WGS data of Clarias batrachus, generated from Roche 454 and Ion Torrent sequencing platforms, to assemble the complete mitogenome using both de novo and reference based approaches. Both the methods yielded almost similar results and the best assembled mitogenome was of 16,510 bp size (GenBank Acc. No. KM259918). The mitogenome annotation resulted in 13 coding genes, 22 tRNA genes, 2 rRNA genes and one control region, and the gene order was found to be identical with other catfishes. Variation analyses between assembled and the reference (GenBank Acc. No. NC_023923) mitogenome revealed 51 variations. The phylogenetic analysis of coding DNA sequences and tRNA supports the monophyly of catfishes. Two SSRs were identified in C. batrachus mitogenome, out of which one was unique to this species. Based on the relative rate of gene evolution, protein coding mitochondrial genes were found to evolve at a much faster pace than the d-loop, which in turn are followed by the rRNAs; the tRNAs showed wide variability in the rate of sequence evolution, and on average evolve the slowest. Among the coding genes, ND2 evolves most rapidly. The variations present in the coding regions of the mitogenome and their comparative analyses with other catfish species may be useful in species conservation and management programs.

The population structure and genetic divergence of Labeo gonius (Hamilton, 1822) analyzed through mitochondrial DNA cytochrome b gene for conservation in Indian waters

Abstract The present study explains the population structure and genetic diversity of medium carp Labeo gonius by analyzing partial sequence of mitochondrial DNA cytochrome b gene. Labeo gonius is a lower risk Near Threatened species, distributed throughout the North Indian major rivers, reservoirs and lakes. This species has a larger scope as an alternative candidate species in carp aquaculture system. In the present investigation, 223 individuals of Labeo gonius were collected from five locations of phylo-geographically isolated riverine ecosystems of India resulted in 12 haplotypes. These haplotypes showed 14 variables, out of which 9 were singletons and 5 were parsimony informative sites of nucleotide positions. The haplotypes H1 was considered as ancestral haplotype. All the haplotypes were connected to each other by 1–4 nucleotide mutations. The Narmada haplotypes (H10; H11 and H12) were isolated from H1 by four nucleotide mutations. The analyses resulted maximum expansion events (τ = 4.13672) in Narmada, with Fst scores more than other population pairs. The analysis of molecular variance (AMOVA) showed significant genetic differentiation among populations (ØST = 0.69470, p < .000). The genetic differentiation patterns were significantly consistence with geographical distributions. This study rejected the null hypothesis of single panmictic population of medium carp, Labeo gonius in Indian water.

Genetic diversity and population structure of Cirrhinus mrigala revealed by mitochondrial ATPase 6 gene

Abstract The genetic diversity and population structure of Cirrhinus mrigala were studied using partial mitochondrial ATPase 6 gene. 155 individuals were collected from six distant rivers of peninsular India. A total of 11 haplotypes were found with haplotype diversity value of 0.46711 and nucleotide diversity 0.00154 indicating a low degree of genetic divergence among populations. The result of AMOVA analysis also revealed that 97.53% of the genetic variation contained within populations and 2.47% occurred among populations. An overall fixation index was found to be 0.02466 (p < .05). Pairwise Fst analysis showed significant genetic differentiation between the Kaveri and rest of the populations. The minimum spanning tree of the haplotype data demonstrated a common ancestral origin of the mrigal populations in peninsular rivers. From the overall results of the present study it may be inferred that mrigal population in peninsular India have low genetic differentiation. This information would be very essential for setting up of genetic improvement programmes, effective management, and conservation of natural genetic resources of mrigal.

Genetic variation in wild and hatchery population of Catla catla (Hamilton, 1822) analyzed through mtDNA cytochrome b region

Abstract Catla (Catla catla) is a one of the most harvested Indian major carps and is widely cultured fish species in Indian subcontinent. In the present study, genetic variability between hatchery and wild stocks of Catla was surveyed using sequence data of mitochondrial DNA of partial 307 bp of cytochrome b region. A total of 174 Catla individuals were examined from three different river basins and hatcheries. Significant genetic heterogeneity was observed for the sequence data (FST = 0.308, p ≤ 0.001). However, analysis of molecular variance (AMOVA) resulted in insignificant genetic differentiation among the samples of three rivers and culture zones (FCT = −0.10, p = 0.44). The result suggested a significant genetic variation within different riverine system, low genetic differentiation among samples from river basins and a lack of genetic variation in hatchery populations.