Table 1

Many genes are regulated in each species. Even in more distantly related fish species, the spots determined to be up-regulated in the brain encompass a great number of unique spots, and are not simply a few genes represented multiple times on the array (n refers to the number of array hybridizations). The estimated number unique genes up-regulated in brain is calculated independently for each species based on the sum of singleton ESTs and the number of genes predicted by clustered ESTs relative to the sequence information available. This result indicates that the redundancy rate for spots determined to be up-regulated in the brain is in agreement with the overall array redundancy and that differences in expression can be detected for mRNAs of low copy number.

Sequenced ESTs

Clustered ESTs

Species

Total number of spots

No sequence available

Singletons

Number of ESTs

Number of clusters

Estimated number of unique genes

A. burtoni (adult) (n = 4)

1146

203

530

413

189

874

A. burtoni (juvenile) (n = 4)

921

172

373

376

171

669

N. brichardi (n = 3)

795

145

302

348

157

561

E. melanogenys (n = 3)

824

152

320

352

156

584

O. niloticus (n = 2)

472

89

164

219

110

338

Xiphophorus sp. (n = 2)

585

126

244

215

121

465

P. reticulata (n = 2)

713

157

323

233

137

590

S. salar (n = 2)

433

99

197

137

83

363

D. rerio (n = 2)

658

141

329

188

130

584

Renn et al. BMC Genomics 2004 5:42   doi:10.1186/1471-2164-5-42