Tandem arrangement of the albumin and alpha-fetoprotein genes in the human genome.

A genomic clone containing human albumin mRNA sequences was isolated from a lambda phage gene library derived from a human hepatoma cell line that produces alpha-fetoprotein (AFP) and albumin. This clone was also found to hybridize with the 5'-flanking region of the human AFP gene. Restriction mapping and nucleotide sequencing revealed that the albumin and AFP genes are present in tandem, in the same transcriptional orientation, with the albumin gene 14.5 kb upstream of the AFP gene. We have also isolated a genomic clone carrying both the albumin and AFP gene sequences from human fibroblasts, which produce neither AFP nor albumin. This DNA showed a restriction map that was indistinguishable from that of the clone obtained from the hepatoma described above, demonstrating that no gross rearrangements of the intergenic DNA sequence are involved in control of expression of the AFP and albumin genes.