Identification of a human heart FABP pseudogene located on chromosome 13.

The fatty acid-binding proteins (FABPs) constitute a conserved group of cytosolic low molecular mass proteins, which consists of several types: liver, heart, myelin, epidermal, adipocyte, brain, intestinal and ileal type. The FABP gene structure is well conserved during evolution and exhibits a four-exon/three-intron structure. In the past, multiple hybridizing fragments were detected upon Southern blot analysis using heart FABP (H-FABP) cDNA as a probe. The origin of these fragments was not clear. We screened a human genomic library and isolated an intronless gene (FABP3-ps) with 85% similarity to the human H-FABP cDNA and high similarity (76 and 79%) to the H-FABP cDNAs of mouse and bovine, respectively. By means of fluorescence in situ hybridization this processed pseudogene could be assigned chromosome 13q13-q14, whereas the gene for human H-FABP (FABP3) resides on chromosome 1p32-p33. No expression of the processed pseudogene could be detected in skeletal muscle or fetal brain.