Physical mapping of the CXC chemokine locus on human chromosome 4

A physical map of the CXC chemokine locus on chromosome 4 has been construc ted by PCR analysis and PFGE mapping of YAC clones. The genes for IL8, GRO1 , PPBP, PF4, SCYB5 (ENA-78) and SCYB6 (GCP-2) have been co-localized on a 3 35-kb genomic fragment. The GRO2 and GRO3 genes did not map within this reg ion and based on analysis of a YAC contig overlapping IL8 we speculate that GRO2 and GR03 map downstream of this region. We have also assigned the nov el CXC chemokine gene, SCYB9B (alias H174/beta R1) to chromosome 4q21, upst ream and within 12 kb of INP10. Like INP10 and MIG, INP10 and SCYB9B are ar ranged in a head to tail manner. The chromosomal arrange ment of these gene s appears to reflect the evolution of this multigene family and supports th e theory that it arose by gene duplication.