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Gene sequence definition biology
Gene sequence definition biology









gene sequence definition biology

  • Based on these models, a great number of ab initio gene prediction programs have been developed.
  • Many algorithms are applied for modeling gene structure, such as Dynamic Programming, linear discriminant analysis, Linguist methods, Hidden Markov Model and Neural Network.
  • The search by this method thus relies on the major feature present in the genes.
  • Exon detection must rely on the content sensors.
  • On the other hand content sensors refer to the patterns of codon usage that are unique to a species, and allow coding sequences to be distinguished from the surrounding non-coding sequences by statistical detection algorithms.
  • Signal sensors refer to short sequence motifs, such as splice sites, branch points, polypyrimidine tracts, start codons and stop codons.
  • gene sequence definition biology

    Ab initio gene predictions rely on two types of sequence information: signal sensors and content sensors.It uses gene structure as a template to detect genes.It is a method based on gene structure and signal-based searches. A new heuristic method based on pairwise genome comparison has been implemented in the software called CSTfinder.Two more types of software, PROCRUSTES and GeneWise , use global alignment of a homologous protein to translated ORFs in a genomic sequence for gene prediction.The most common local alignment tool is the BLAST family of programs, which detects sequence similarity to known genes, proteins, or ESTs.

    gene sequence definition biology

  • Local alignment and global alignment are two methods based on similarity searches.
  • Once there is similarity between a certain genomic region and an EST, DNA, or protein, the similarity information can be used to infer gene structure or function of that region.
  • This approach is based on the assumption that functional regions (exons) are more conserved evolutionarily than nonfunctional regions (intergenic or intronic regions).
  • It is a conceptually simple approach that is based on finding similarity in gene sequences between ESTs (expressed sequence tags), proteins, or other genomes to the input genome.
  • It is a method based on sequence similarity searches.











    Gene sequence definition biology