Epartment of Personal computer Science,Strada Le Grazie ,Verona,ItalyWorking on genomic dictionaries calls for the elaboration of massive moles of data. As an instance,the dictionary of all of the substrings of length occurring in Drosophila melanogaster’s genome has greater than millions of words,which demand,only to become stored,nontrivial implementations of ad hoc procedures. For the very best of our understanding,exhaustive studies on collections of kmers were carried out for Sapropterin (dihydrochloride) values of k which do not exceed (see for instance ). The beginning point of our evaluation was the computation of all kmers,with kof provided genomes,listed in Table . Some properties of such certain dictionaries and their compared statistics guided our research along lines of development which were in aspect currently present within the literature ,and in aspect took us towards new subjects,which emerged just in the empirical proof of computed information. An fascinating notion in this Castellini et al, licensee BioMed Central Ltd. This is an Open Access report distributed beneath the terms of the Inventive Commons Attribution License (http:creativecommons.orglicensesby.),which permits unrestricted use,distribution,and reproduction in any medium,provided the original perform is properly cited.Castellini et al. BMC Genomics ,: biomedcentralPage ofTable A list of genomes investigated within the paperOrganism Genome Nanoarchaeum equitans Mycoplasma genitalium Mycoplasma mycoides Haemophilus influenzae Escherichia coli Pseudomonas aeruginosa Saccharomyces cerevisiae Sorangium cellulosum Homo sapiens chr. Caenorhabditis elegans Drosophila melanogaster Homo sapiens chr. Length (in bp),,,,,,,,,,,,,,,,,,,Genes ,,,,,,,Form Minimal archaeum Minimal bacterium Venter’s experiment bacterium Very first sequenced bacterium Bacterium model (K) Ubiquitous bacterium Unicellular eukaryote (Yeast) Longest genome bacterium Highest gene density H. chromosome Worm (about cells) Insect (fruit fly) Longest Human chromosomecontext is the fact that of hapax (a Greek term,which means “once”,coming from philology,exactly where it is applied for denoting a “word mentioned once”). In manuscripts these words are relevant for authorship attribution,in genomes they seem to play critical roles in the genome organization as opposed to repeat strings,which as an alternative take place greater than after. In Table a list is reported of twelve (out of the sixty we’ve investigated) genomic sequences,to which we applied the methodology described beneath. They correspond to genomes of well known organisms,constituting biological models,of relevance in various types of genomic evaluation. The sequences were downloaded from public internet sites as FASTA files,and processed by a dedicated Java application that we created. Inside the following simple terminology for genomic dictionaries and multisets,and genomic PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/22394471 profilesdistributions,is introduced,as well as a straightforward instance focused on a distinct DNA sequence. Results are reported when it comes to each an evaluation of dictionaries of klong hapaxes and repeats,collectively together with the introduction of 3 related dictionarybased informational indexes,along with the definition of krepeat sharing gene networks. Section Discussion is then developed around a phasetransition observed in kdictionaries from k to k ,and about the structure of genomic data which emerges when dictionary cardinality trends and multplicitycomultiplicity distributions are compared with those of randomly permuted sequences. A description with the computer software suite created to perform all our computations is ultimately pr.