Identification and Characterization of an MGSA/GRO Pseudogene

Three linked genes for the CXC-chemokine melanoma growth stimulatory activity/growth related protein (MGSA/GRO) have been previously characterized and mapped to chromosome 4ql2-ql3. We have isolated and characterized a pseudogene, MGSA/GROδ, which is 83% similar to the MGSA/GROα gene in the region spanning the 5′ UTR, first and second exons, and the first intron. The 5′ upstream sequence for the MGSA/GROδ gene, which is also very similar to the MGSA/GROα, β, γ genes, contains a conserved NF-KB motif, a TATA box, and a transcription initiation site. However, the sequence becomes markedly divergent after the second exon and hybridization studies indicate that sequences similar to the third and forth exons of other MGSA/GRO genes are not present in this gene. Additional sequence differences include alteration of the MGSA/GROδ translation initiation codon and a one base insertion resulting in an apparent frame shift and early termination within exon 2. Multiple mutations such as these are characteristic of ps...