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Deciphering the genetic and molecular mechanisms controlling the development of the root system and its adaptive plasticity under adverse environments is of primary importance for the sustainable establishment of the rice crop. Rice displays a complex root structure comprising several root types mostly of postembryonic origin. The large natural variation in root architecture among cultivars reflects their adaptation to contrasting agro-environmental conditions. This article reviews the current knowledge on the organization and anatomy of the various types of roots of the fibrous root system of rice, the diversity and genetic basis of natural variation of root system architecture and performance, and the molecular mechanisms underlying constitutive and adaptive root development. This paper also throws light on how the integrated approach of new tools in high-resolution microscopy imaging, expression profiling, mutant screening, and reverse genetics could facilitate the rapid discovery and analysis of the key genes and regulatory networks involved in root architectural traits affecting plant performance under field conditions.

Genetic variation detected by new molecular techniques provides a powerful but somewhat controversial tool for assisting, in identifying the source of forensic specimens. A DNA match between a forensic specimen and a suspect has little probative value without an appreciation of the extent of variation within the population of possible culprits. Genetic sequences that are highly variable are, in principle, the most powerful for establishing the genetic identity of samples, but differences between human populations in the frequency of genes and the non-random pattern of human mating create difficulties in accurately quantifying the likelihood of a match at random. If gene frequencies are generally low and the variation between subpopulations significant but ignored, the probability of a match is likely to be overestimated (Wahlund phenomenon), favouring the suspect. Associations between genes at different loci (linkage disequilibrium) can also seriously influence estimates of the match probability, especially in populations recently formed as an aggregate of several distinct groups.

One method of taking cognisance of these difficulties, ‘the ceiling principle’, was designed to give an upper estimate of the match probability and hence favour the suspect. While this method generally produces a conservative estimate, it does not have some basic properties considered fundamental in scientific estimation - the most important of which is that one cannot attach to the probability an estimate of uncertainty or error. The fixation index F_ST, which measures the extent of genetic variation between groups, is a far more powerful way of correcting for population substructure. However, no method is satisfactory if the extent of variation (at the genetic sequences being utilised) in the relevant forensic population is not well understood, and this is the greatest impediment to the application of DNA variation. Also, extremely low probabilities of a match at random have little meaning if the rate of errors in other parts of the process (such as mixing samples, laboratory mistakes, etc) is significantly greater. The controversy that this particular application of molecular biology in the forensic setting has made highlights the necessity of inter-disciplinary co-operation between several distinct subdisciplines of both the scientific and legal professions if the introduction of new technologies and methodologies is to proceed efficiently and fairly.

The team’s initial hypothesis states that the Mereon Matrix’s First Principles constitute a unitive template generally applicable as an information model. For verification of this premise, the knowledge domain of human molecular genetics was used in a study called ATCG. The Matrix’s seven functions and its fractal principle were applied using the latest (at the point of writing, i.e. up to the beginning of the year 2013) original scientific literature as the source of domain information. ATCG was elaborated through all seven functions with each further explored through its level of micro-functions. The Mereon Matrix was extremely useful in modelling as it constantly forced authors to pose specific questions with respect to the topics inherent at different micro-functions. This allowed searching for answers in the literature using an iterative and incremental modelling process. Upon completing the project it was concluded that the Mereon Matrix as a template for modelling human molecular genetics met and exceeded what was anticipated.