CHROMOSOMAL LOCALIZATION, GENOMIC STRUCTURE, AND ALLELIC POLYMORPHISMOF THE HUMAN CD79A (IG-ALPHA MB-1) GENE/

The germline DNA sequence of the human CD79a (Ig-alpha/mb-1) gene was determined by polymerase chain reaction sequencing of a cosmid clone d erived from an arrayed human chromosome 19 library. The CD79a gene was localized to chromosome 19q13.2; this localization places the gene wi thin the CEA-like gene cluster with the following gene order: -CEA-CGM 1-CD79a-RPS11-ATP1A3-BGP-CGM9-. The genomic organization of the human CD79a gene resembles the mouse counterpart with five exons interrupted by four introns. Computer analyses suggest the presence of transcript ion regulatory elements known to be important in the regulation of mou se CD79a (AP-1, EBF, AP-2, MUF2, and SP-1 sites), as well as elements not found in the mouse gene (an NF-kappa B binding site and a series o f E-box motifs). Similar to the mouse gene, the 5' flanking region of human CD79n lacks a TATA box; however, unlike mouse CD79a, a classical octamer motif could not be identified in the human gene. Finally, a n ew Rsa I restriction fragment length polymorphism was defined in the n on-coding regions of the human gene.