ANEXdb: an integrated animal ANnotation and microarray EXpression database.

Area of Science:

• Bioinformatics
• Genomics
• Livestock Science

Background:

• Microarray experiments in livestock species often suffer from sparse sequence element annotations.
• Researchers currently face challenges in obtaining or creating necessary annotations for accurate transcriptional profiling.

Purpose of the Study:

• To develop and present ANEXdb, a web application providing integrated access to microarray expression and EST annotation data for livestock species.
• To enhance the annotation of porcine microarray elements and identify sequence variations in expressed genes.

Main Methods:

• ANEXdb integrates ExpressDB (microarray expression data) and AnnotDB (EST annotation data).
• AnnotDB houses the Iowa Porcine Assembly (IPA), a novel assembly of porcine expressed sequence reads, annotated via homology to NCBI RefSeq.
• Porcine probe sets were mapped to annotated sequences, and sequence variation (SNPs, deletions, insertions) was identified in the Iowa Tentative Consensus (ITC) sequences.

Main Results:

• ANEXdb provides integrated access to expression and annotation data.
• 94% of porcine microarray probe sets are annotated, with 80% linked to NCBI RefSeq entries.
• Over 200,000 SNPs and thousands of deletions/insertions were identified in porcine expressed sequences.

Conclusions:

• ANEXdb offers a centralized resource for porcine gene annotation and sequence variation data.
• This facilitates the identification of causal variants in differentially expressed genes within livestock expression experiments.
• The open-source ANEXdb application aims to advance livestock genomics research.