Profile Comparison
In 1987 Michael Gribskov, Andrew McLachlan and David Eisenberg introduced the method of profile comparison for identifying distant similarities between proteins. Rather than using a single sequence, profile methods use a multiple sequence alignment to encode a profile which contains information about the conservation level of each residue. These profiles can then be used to search collections of sequences to find sequences that are related. Profiles are also known as Position Specific Scoring Matrices (PSSMs). In 1993 a probabilistic interpretation of profiles was introduced by David Haussler and colleagues using hidden Markov models. These models have become known as profile-HMMs.
In recent years methods have been developed that allow the comparison of profiles directly to each other. These are known as profile-profile comparison methods.
Read more about this topic: Sequence Analysis
Famous quotes containing the words profile and/or comparison:
“Actor: Electrician, a little more this way with that spotlight. What are you trying to do, ruin my profile?
Electrician: Your profile was ruined the day you were born.”
—James Gleason (1886–1959)
“It is very important not to become hard. The artist must always have one skin too few in comparison to other people, so you feel the slightest wind.”
—Shusha Guppy (b. 1938)