arXiv subjects

Eberto Morgado

Publications and source records attributed to Eberto Morgado.

4 recordsLinked to original sources

arXiv2005

Abelian Finite Group of DNA Genomic Sequences

The Z_64-algebra of the genetic code and DNA sequences of length N was recently stated. In order to beat the limits of this structure such as the impossibility of non-coding region analysis in genomes and the impossibility of the insertions and deletions analysis (indel mutations), we have develop a cycle group structure over the of extended base triplets of DNA X_1X_2X_3, X_i belong to {O, A, C, G, U}, where the letter O denote the base omission (deletion) in the codon. The obtained group is isomorphic to the abelian 5-group Z_125 of integer module 125. Next, it is defined the abelian finite group S over a set of DNA alignment sequences of length N. The group S could be represented as the direct sum of homocyclic groups: 2-group and 5-group. In particular, DNA subsequences without indel mutation could be considered building block of genes represented by homocyclic 2-groups (described in the previous Z_64-algebra). While those DNA subsequences affected by indel mutations are described by means of homocyclic 5-groups. This representation suggests identify genome block structures by way of a regular grammar capable of recognize it. In addition, this novel structure allows us a general analysis of the mutational pathways follow by genes and isofunctional genome regions by means of the automorphism group on S.

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arXiv2004

The Genetic Code Boolean Lattice

The algebraic structures of the genetic code are most important to obtain additional information about the semantic code and its applications. In this paper we define two dual Boolean codon lattices of the genetic code using hydrogen bond numbers and the chemical types of bases: purines and pyrimidines. The Boolean lattices reflect the role of hydrophobicity in the distribution of codon assignments to each amino acid. Particularly, the symmetric images of codons with adenine as second base coding to hydrophilic amino acids are always codons with uracil as second base coding to hydrophobic amino acids as they represented in the Hasse diagrams. The Hamming distance between two codons in the Hasse diagram reflects the different hydrophobicities between their respective coded amino acids. Our experiments have demonstrated a small Hamming distance to the wild type HXB2 of almost all the drug-resistant reported mutations in HIV protease gene. The human beta-globin mutant genes have also exhibited similar results. Our research suggests that the Hamming distance between two genes in the molecular evolution process have a minimal value.

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arXiv2004

Gene Algebra from a Genetic Code Algebraic Structure

The biological distinction between the base positions in the codon, the chemical types of bases (purine and pyrimidine) and their hydrogen bond number have been the most relevant codon properties used in the genetic code analysis. Now, these properties have allowed us to build a Genetic Code ring isomorphic to the ring (Z64, +,*) of the integer module 64. On the Z64-algebra of the set of 64^N codon sequences of length N, gene mutations are described by means of endomorphisms F: (Z64)^N->(Z64)^N. Endomorphisms and automorphisms helped us describe the gene mutation pathways. For instance, 77.7% mutations in 749 HIV protease gene sequences correspond to unique diagonal endomorphisms of the wild type strain HXB2. In particular, most of the reported mutations that confer drug resistance to the HIV protease gene correspond to diagonal automorphisms of the wild type. What is more, in the human beta-globin gene a similar situation appears where most of the single codon mutations correspond to automorphisms. Hence, in the analyses of molecular evolution process on the DNA sequence set of length N, the Z64-algebra will help us explain the quantitative relationships between genes.

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arXiv2004

A New DNA Sequences Vector Space on a Genetic Code Galois Field

A new n-dimensional vector space of the DNA sequences on the Galois field of the 64 codons (GF(64)) is proposed. In this vector space gene mutations can be considered linear transformations or translations of the wild type gene. In particular, the set of translations that preserve the chemical type of the third base position in the codon is a subgroup which describes the most frequent mutations observed in mutational variants of four genes: human phenylalanine hydroxylase (PAH), human beta globin (HBG), HIV-1 Protease (HIVP) and HIV-1 Reverse transcriptase (HIVRT). Furthermore, an inner pseudo-product defined between codons tends to have a positive value when the codons code to similar amino acids and a negative value when the codons code to amino acids with extreme hydrophobic properties. Consequently, it is found that the inner pseudo-product between the wild type and the mutant codons tends to have a positive value in the mutational variants of the genes: PAH, HBG, HIVP, HIVRT.

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