Representative expression profiles of HVS genes in mouse tissues. HVS mRNA expression levels in the mouse brain (B), muscle (M), lung (Lu), spleen (S), heart (H), liver (Li), kidney (K), and testis (T) were analyzed by semiquantitative RT-PCR. Rhbdd1 and other (total 11 genes) mRNAs are ubiquitously present in the above tissues. Expressions of Pcyoxl and Pnrc1 (Additional file 3) mRNAs and those of C530028I08Rik and Rad18 (Additional file 3) were abundant in the brain and testis, respectively. 4933429F08Rik and other (total 7 genes) mRNAs were predominantly expressed in the brain and testis. See also Additional file 3. LOC631847 and 5430433G21Rik mRNAs were primarily detected in the lung. Snx24 mRNA is expressed in the spleen. The remaining 20 mouse HVS genes show various "tissue-selective" expression patterns, as shown in Additional file 4.