GMO’s are making a big revolution in science as such organisms are much exploited for the benefit of man and environment. E. coli has been engineered to produce n-butanol as fuel substance. The production of biofuels also depends on breakdown of cellulose by cellulase into simple sugars which are further converted into fuel substances from switch grass—a cellulose rich feed stock. Recent studies in genetic epidemiology established association of genetic variants with brain cancer, loss of function polymorphism in tumor suppressor gene in breast cancer, whereas smoking tobacco influences methylation changes in DNA associated with lung cancer, MC1R genotype influences melanoma risk. However, we present papers in this issue which encompass findings of polymorphic genes and their exploitation and association for the benefit of living organisms.

The paper, “Mismatch Cleavage by CEL-I Endonuclease: A Tool for Rapid Detection of Homozygous and Heterozygous Mutants”, by Sulabha Sharma, Kamal Tyagi, M Lakshmi Narasu, Y Sreelakshmi and Rameshwar Sharma presented a rapid tool for identifying the homo/heterozygous nature of the plants by simple digestion of PCR amplified genomic DNA with CEL-I Endonuclease followed by agarose gel electrophoresis which can be used in developing countries where instrumentation access is limited.

The next paper, “Association of ADAM33 Gene Polymorphisms with Reduction of Lung Function as Measured by Peak Expiratory Flow Rate Among Healthy Male Smokers and Nonsmokers”, by Priya Tripathi, Shally Awasthi and Subramaniam Ganesh revealed that the gene ADAM33 is associated with lung function where smoking is found to be a precipitating factor. Only among smokers, mean difference of Peak Expiratory Flow Rate (PEFR) was statistically significantly lower in heterozygous genotypes when compared to mutants of SNP V4. This may possibly be explained on the basis of gene-environmental interaction.

The authors, S D Wahi and A R Rao of the paper, “Some Investigations on Sampling Variance of Genetic Correlation”, made an attempt to compare various estimates of standard errors and mentioned bootstrap errors as the best estimates for heritability based on their observations that the bootstrap estimates of standard error which are very close to predicted values can be used to estimate the standard error instead of approximate formulae given in literature. It is also found that in the case of non-normal datasets with sire effects following gamma distribution, the bootstrap estimates of standard error of genetic correlation are always underestimated.

The authors, Lawa Hari Nepal, R Basavaraju and R S Sai Murali in their paper, “A Study of Callogenesis and Morphogenesis in Phyllanthus niruri L.”, discussed various combinations of nutrient media and their protocols in the callogenesis and morphogenesis in Phyllanthus niruri—a medicinal plant. The morphogenic response of Phyllanthus niruri has been carried out in MS medium with BA, IBA, NAA, Ad, 2, 4-D and Kn. The nodal explants treated with BA showed good establishment and also the formation of multiple shoots up to 20 in 2 mgL–1. Nodal explants with IBA treatment revealed good establishment and also produced multiple shoots around 15-16 in 3 mgL–1. The nodal explants in the treatments of BA + Kn and IBA + Kn revealed good organogenesis in MS medium. The combination of NAA + KN and 2, 4-D + Kn revealed significant callogenesis. Nodal explants and apical meristem in MS medium with coconut milk exhibited good shoot, root growth and formation of some amount of callus in 10 mLL–1. The last paper, “Heavy Metal Resistance Among Azotobacter Spp and Their Survival in HM Contaminated Soil Using Indian Mustard”, by Neeru Narula, Rishi K Behl and Erika Kothe is an attempt to study the heavy metal resistance in a nitrogen fixing bacteria which promotes better interaction with plants. 17 different Azotobacter isolates were checked for their resistance to various heavy metals which are predominate in contaminated wismut soil on agar media plates containing 0.02, 0.1, 1-3 mM of Al, Pb, Ni, Cr and Cd. High bacterial numbers were observed in garden soil with and without inoculation, whereas contaminated soil showed low bacterial numbers. Root and shoot weights were more in inoculated plants grown in wismut soil compared to garden soil indicating improved interaction with plants.

-- V Venugopal Rao
Consulting Editor