Physical and meiotic mapping of the region of human chromosome 4q11-q13 encompassing the vitamin D binding protein DBP/Gc-globulin and albumin multigene cluster

The vitamin D binding protein/Gc-globulin (DBP) gene is a member of a multi gene cluster that includes albumin (ALB), oc-fetoprotein (AFP), and alpha-a lbumin/afamin (AFM). All four genes have structural and functional similari ties and map to the same chromosomal regions in humans (4q11-q13), mice, an d rats. An accurate physical map of the region encompassing these genes is a prerequisite for study of their respective transcriptional regulation and identification of potential shared regulatory elements. By refining the ph ysical and meiotic maps of the 4q11-q13 region and creating a local PAC con tig, the order and transcriptional orientations of these four genes were de termined to be centronlere-3'-DBP-5'-5'-ALB-3'-5'-AFP-3'-5'-AFM-3'-telomere . The ancestral DBP gene was separated from the ALE gene by >1.5 Mb. This o rganization and spacing establishes a foundation for ongoing functional stu dies in this region.