About Sequence Alignment
[Sequence alignment]
Definition
It is a method of arranging the biological sequences (DNA, RNA, or protein) and determining the relationships of given molecules that can be interpreted into the information about evolution. Through inserting some gaps in sequence matrix composed of nucleotides or amino acids, the identities or similar characteristics between each string is analyzed. In detail, the point mutation, gaps generated by insertion or deletion of several nucleotides (or amino acids) can be easily detected. And the conservation rate of strings also can be calculated.
Methods
If the target sequence, which is very short like 10~20 nucleotide long, is given, it could be aligned manually. But the information needed in real medical science is too lengthy to be analyzed by only human effort. In that sense, there are hundreds of softwares developed by many companies that can conduct sequence alignment of all DNA, RNA, and proteins in these days. As all those methods invented to compare the potential sequence alignments, each method has its own formulas to determine the values for each alignment. The formulas are known as objective functions which mean that the data range from simple to complex values. And those are generally divided into two categories, global and local alignments. Global alignments span the whole region of sequences, but local alignments select some similar region in lengthy strings. The local alignments are better for precise analysis but it is more difficult than global alignments due to the selection of similar region within huge group of biomolecules.
Reference
