 ) COLLATE=utf8_general_ci ENGINE=MyISAM;
 
 /**
+ * Genomic feature cross-reference from other datasources.
+ */
+CREATE TABLE xref (
+
+    id                        INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
+    acc                       VARCHAR(20) NOT NULL,
+    db_id                     INT(10) NOT NULL,
+    xref_acc                  VARCHAR(20) NOT NULL,
+    xref_db_id                INT(10) NOT NULL,
+    
+    PRIMARY KEY (id),
+    KEY genomic_feature_idx (acc, db_id),
+    KEY xref_idx (xref_acc, xref_db_id)
+    
+) COLLATE=utf8_general_ci ENGINE=MyISAM;
+
+/**
  * Allele table
  * Contains sequence variant of a gene recognized by a DNA assay (polymorphic)
  * or a variant phenotype (mutant)

DROP TABLE IF EXISTS text_observation;
DROP TABLE IF EXISTS time_series_observation;
DROP TABLE IF EXISTS unidimensional_observation;


/**
@table project
@desc This table stores information about each phenotyping project

--
-- Drop all the tables if they exist
--
DROP TABLE IF EXISTS meta_info;
DROP TABLE IF EXISTS allele;
DROP TABLE IF EXISTS biological_model;
DROP TABLE IF EXISTS biological_model_allele;
