You may attend all three of the classes in this series, or any combination. Classes are free, but you must sign up.

Basic Local Alignment Search Tool (BLAST) is considered the de facto sequence similarity search algorithm used in various fields of molecular biology. This workshop will begin with an overview of sequence similarity and continue with an understanding of scoring matrices as they relate to alignments. We will then focus on the probabilistic terms related to the BLAST algorithm. This workshop should lay the foundation for understanding the different versions of BLAST which are widely used but often misunderstood and incorrectly applied.

The BLAST algorithm, since its inception, has taken on many forms and improvements over the years. This workshop will focus on the basic implementation of the algorithm and give the user a thorough understanding of recent advancements such as the two-hit method and the use of position specific scoring matrices (PSSM). Before attending this workshop, participants should have a basic understanding of sequence similarity and scoring matrices.

One should consider BLAST a family of programs rather that a stand-alone algorithm. In the standard BLAST distribution, for example, there are more than half a dozen variations of BLAST. This workshop will focus on the different versions used at NCBI, with an in-depth look at the parameters involved with each. During the workshop, we will cover the different NCBI BLAST versions, focusing on their method variations and subsequently their individual applications to particular problems.