Definitions

Average value/individual tissue sample:

An expression level is generated for each gene according to the algorithms within the GeneChip 3.1 Analysis software. In cases where test data from more than one sample of a given tissue is available, the user may opt to view the average of the expression levels for each gene across all samples for a given tissue.

Gene Name:

The displayed gene names are edited versions of Entrez definitions taken from the National Center for Biotechnology Information (NCBI) Entrez database. All genes are human clones whose actual Entrez description can be obtained by searching the NCBI website using the desired gene's accession number.

Accession Number:

The database accession number associated with each gene corresponds to the GenBank accession number of the sequence, assigned to the nucleotide, protein, structure, or genome record by a sequence database builder as provided by NCBI.

LocusLink ID:

LocusLink is a curated NCBI database designed to provide a single identification number or ID for every individual gene locus (i.e., gene). It provides a reference sequence as well as descriptive information about genetic loci. It presents information on official nomenclature, aliases, sequence accession numbers, phenotypes, EC numbers, MIM numbers, UniGene clusters, map information, and relevant web sites. Clicking on the LocusLink ID will take you to the page describing the gene of interest at LocusLink. Many of our genes do not have a LocusLink ID number because the LocusLink database is incomplete and being continually updated. For further questions regarding LocusLink, please refer to their url.

Function:

The function(s) of each gene are assigned according to known literature or structural homology. This category is not yet functional and will be available in the future. In many cases, LocusLink can provide links to literature describing functions of genes. We welcome suggestions regarding functional classification of particular genes.

Tissue:

All tissue samples are from normal human specimens in the course of standard surgical procedures with IRB approval. Unless otherwise specified, please assume that the expression levels for a given dataset represent a uniform sampling of the described tissue. A pathologist has examined the histological sections to confirm the identity and condition of each tissue.

Sample ID:

Each tissue sample is uniquely identified so that variation among individuals can be tracked. Moreover, we provide very limited demographic information such as gender and age (see Sample Information) to assist in data evaluation.

Expression Level:

The expression level is provided in arbitrary units that range from 0 to approximately 10,000. Basically, the data are normalized so that the total fluorescent signal on the entire chip is a constant. All samples undergo the same normalization and scaling procedures as described in Data Analysis.

P/A/M:

Each gene for a given sample has been assigned an absolute call of Present (P), Absent (A), Marginal (M), or Present/Absent (P/A). This parameter is designed to distinguish specific from non-specific hybridization using empirically derived rules involving an analysis of the perfect match and mismatch hybridization signals. Marginal genes are those that showed some non-specific hybridization signal but nonetheless are likely present. They could also suggest the presence of homologs or alternative splice variants. Absent genes, in some cases, exhibit a significant level of expression that is related to the signal being largely non-specific hybridization.