The GHMM is a freely available C library implementing efficient data structures and algorithms for basic and extended HMMs with discrete and continous emissions.
GlimmerHMM is a new gene finder based on a Generalized Hidden Markov Model (GHMM). Although the gene finder conforms to the overall mathematical framework of a GHMM, additionally it incorporates splice site models adapted from the GeneSplicer program and a decision tree adapted from GlimmerM. It also utilizes Interpolated Markov Models for the coding and noncoding models . Currently, GlimmerHMM’s GHMM structure includes introns of each phase, intergenic regions, and four types of exons (initial, internal, final, and single).
GQL (Graphical Query Language) is a suite of tools for analyizing time-course experiments. Currently, it is adapted to gene expression data. The two main tools are GQLQuery, for querying data sets, and GQLCluster, which provides a way for computing groupings based on a number of methods (model-based clustering using HMMs as cluster models and estimation of a mixture of HMMs).
GeneZilla (formerly known as TIGRscan) is a state-of-the-art program for computational prediction of protein-coding genes in eukaryotic DNA, and is based on the Generalized Hidden Markov Model (GHMM) framework, similar to GENSCAN and GENIE. It is highly reconfigurable and includes software for retraining by the end-user. Graph-theoretic representations of the high scoring open reading frames are provided, allowing for exploration of sub-optimal gene models. It utilizes Interpolated Markov Models (IMMs), Maximal Dependence Decomposition (MDD), and includes states for signal peptides, branch points, TATA boxes, CAP sites, and will soon model CpG islands as well.
ExAlt is a software program designed to predict alternatively spliced overlapping exons in genomic sequence. The program works in several ways depending on the available input. ExAlt can use information about existing gene structure as well as sequence conservation to improve the precision of its predictions. ExAlt can also make predictions when only a single genomic sequence is available.