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K V Bhat

Publications and source records attributed to K V Bhat.

9 recordsLinked to original sources

Analysis of Indian population based on Y-STRs reveals existence of male gene flow across different language groups.

A study of three different Y-specific microsatellites (Y-STRs) in the populations from Uttar Pradesh (UP), Bihar (BI), Punjab (PUNJ), and Bengal (WB), speaking modern indic dialects with its roots in Indo-Aryan language, and from South of India (SI), speaking the South Indian languages with their root in Dravidian language, has shown that the predominant alleles observed represent the whole range of allelic variation reported in different population groups globally. These results indicate that the Indian population is most diverse. The similarity between the allelic variants between the populations studied by others in Africa and Asia and in this study between WB, PUNJ, UP, BI, and SI are of interest. It demonstrates that these population groups, housed in eight states of the country in different geographic locations, broadly correspond with Indo-Aryan and Dravidian language families. Further, our analyses based on haplotype frequency of different marker loci and gene diversity reveals that none of the population groups have remained isolated from others. High levels of haplotype diversity exist in all the clusters of population. Nonsignificant results based on Markov chain steps and Slatkin's linearized genetic distances indicate that there has been migration to and from in these population groups. However, some of the marginally significant interpopulation differences could be attributed to one or more of the castes with high diversity embedded within the population groups studied. Haplotype sharing between populations, F(ST) statistics, and phylogenetic analysis identifies genetic relatedness to be more between individuals belonging to two different states of India, WB and PUNJ, followed by UP and BI, whereas SI branched out separately.

Alleles↗

Phylogenetic relationships and genetic polymorphisms in wild Indian mice.

Randomly amplified polymorphic DNA (RAPD) analysis was used to examine the extent of variability in 11 Indian wild derived commensal house mice (Mus musculus) populations and compared with inbred strains of musculus and domesticus subspecies as well as commonly used laboratory inbred strains C57BL/6J and DBA/2J. Arbitrary designed 10 mer oligonucleotide primers with 60-70% (G+C) content were used to amplify DNA template. Out of 52 primers screened initially on the laboratory strains, 20 were selected for analysis on the basis of amplification product in the size range of 200-1400 bp. Among 353 total polymorphic bands, 220 bands (64%) were found to be polymorphic in Indian wild mice, 85 bands (25%) in wild derived inbred strains and 37 bands (11%) in laboratory mice strains. The amplification patterns produced by primers were statistically analysed by Jaccard's similarity coefficient the value of which ranged from 0.56 to 0.80. High level of genetic diversity was seen in the Indian wild mice populations as compared to the controls. The UPGMA phenogram grouped mice population into two major clusters except Bikaner [BIK], Bilaspur [BIL] and Ranikhet [RK] populations which were placed outside the close-knit clusters. Inspite of low values of bootstrap estimates obtained by Wagner and Dollo parsimony analysis, the results were comparable with UPGMA phenogram when constitution of the populations in the major cluster was considered. Indian mice populations appeared to be diverse from laboratory inbred mice strains.

Animals↗

Random amplified polymorphic DNA (RAPD) analysis in Indian mung bean (Vigna radiata (L.) Wilczek) cultivars.

Greengram [Vigna radiata (L.) Wilczek], also known as mung bean, widely cultivated in a large number of countries, is an important pulse crop of Asia and is considered one of the ancestral species of the genus Vigna. Since yields of greengram have remained low across subtropical and tropical Asia, it is important to estimate genetic diversity in existing cultivars in order to see if the lack of genetic variability might be a constraining factor. In this study, 32 Indian cultivars of greengram were subjected to random amplified polymorphic DNA (RAPD) analysis using 21 decamer primers. A total of 267 amplification products were formed at an average of 12.71 per primer with an overall polymorphism of 64%. The extent of polymorphism was moderate to low. Jaccard similarity coefficient values ranged from 0.65 to 0.92. The cluster analysis resulted in mainly three clusters revealing greater homology between cultivars released from the same source. The results of principal components analysis also substantiated this conclusion. The close genetic similarity between the cultivars could be explained due to the high degree of commonness in their pedigrees. The narrow genetic base of the greengram cultivars revealed in the present analysis emphasises the need to exploit the large germplasm collections having diverse morphoagronomic traits in cultivar improvement programs.

Crops, Agricultural↗

Genetic heterogeneity in the Indian Mus musculus.

This study deals with the characterization of 10 populations of M. musculus from different geographical locations in India. The genetics of Indian wild mice has been completely obscure and this is the first report on allozyme variations in the natural population. We have used a set of 24 biochemical genetic markers to measure levels of diversity within and among populations. The allelic frequency data indicate extreme genetic variability, which is further enhanced by the presence of novel alleles. Overall the species shows a high level of heterogeneity. The highly polymorphic central populations of M. musculus cannot be assigned to any one particular subspecies. The allelic profiles, however, indicate a gradual differentiation toward the castaneus and batcrianus subspecies lineages.

Animals↗

Detection of species-specific genetic markers in farm animals through random amplified polymorphic DNA (RAPD).

The potential use of random amplified polymorphic DNA (RAPD) was evaluated as a source of development of alternative genetic markers for studying variation in buffalo (Bubalus bubalis) and other related species of the Artiodactyla family Bovidae, in order to ascertain genetic relationships and diversities. Fourteen arbitrary primers were used to amplify DNA fragments in four species such as Indian Zebu cattle (Bos indicus), buffalo (Bubalus bubalis), sheep (Ovis aries) and goat (Capra hircus). Clear and distinct RAPD patterns with a higher level of polymorphism was detected between species, while fewer polymorphisms were found within the species. Species were subsequently scored for presence or absence of RAPD fragments and Jaccard's similarity coefficients were calculated to quantify the genetic divergence among the species. Wagner parsimony analysis of the RAPD data for 542 markers resulted in one most parsimonious tree which revealed very low similarity among the four species analysed.

Animals↗

DNA profiling of banana and plantain cultivars using random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers.

Polymerase chain reaction (PCR) amplification of genomic DNA from 57 Musa cultivars with 60 random 10-mer primers generated 605 polymorphic amplification products which were useful in unambiguous cultivar identifications. Unweighted pair-group method analysis of this data grouped the cultivars into specific clusters depending on their genomic similarities. The diploid ancestral species of cultivated banana and plantains, namely Musa acuminata sp malaccensis, an A genome donor and M. balbisiana, a B genome donor, were farthest apart from each other in the phenogram. The edible fruit yielding cultivars with the genomic constitutions AA, AAA, AB, AAB, ABB, and ABBB grouped in different clusters according to overall genetic homologies. The restriction fragment length polymorphisms (RFLPs) prevalent among the cultivars were studied by hybridization of 19 random genomic clones to blots of HindIII, EcoRI and MspI digests. Cluster analysis of these data on 107 polymorphic alleles resulted in a phenogram comparable to the one obtained with random amplified polymorphic DNA (RAPD) analysis. Two multilocus probes useful in distinguishing all the 57 cultivars analyzed were also identified. The A and B types of cytoplasms in the cultivars were further distinguished by hybridization of heterologous chloroplast DNA probes. Results showed that use of different kinds of molecular markers in gene banks is essential for characterization and classification of germplasm collections.

Base Sequence↗

DNA fingerprinting of Musa cultivars with oligodeoxyribonucleotide probes specific for simple repeat motifs.

Using synthetic oligodeoxyribonucleotide probes against restriction-digested genomic DNA, we have established DNA fingerprinting of Musa cultivars. Of all the enzymes used, Eco RI and Hin dIII were found to be most informative, giving rise to individual specific band patterns with oligonucleotide probes of 15- to 18-base residues. Of the several probes and enzyme combinations used, the 15mer GACA probe with Eco RI and Hin dIII digests revealed a maximal level of polymorphism, and the probability of obtaining an identical band pattern between any two random genotypes was calculated to be 1.50 x 10(-9) and 1.59 x 10(-9), respectively. Oligonucleotide probes longer than 22 residues were also used but did not hybridize. The present approach is useful for cultivar identification and for overall genome analysis to establish relatedness among the various accessions of the Musa germplasm originating from different geographic locations. The relevance of using synthetic oligonucleotide probes based on simple repeat motifs for achieving DNA fingerprinting pattern is discussed.

Base Sequence↗