The complete nucleotide sequence of a human immunoglobulin genomic C mu gene.

We report here the DNA sequence of a genoraic Cv clone that includes the membrane exons. This clone among others was isolated by us from a HeLa cell library by screening with a DNA fragment containing a portion of exon 1 and exon 2 of the human Cfi gene which was derived from a cDNA clone of the human mu gene isolated in this laboratory. The sequence reported here is consistent with the partial nucelotide sequence reported previously (2) with minor changes. The amino acid sequence deduced from the nucleotide sequence is mostly consistent with that which is determined by Edman degradation procedure (3). The splice sites (T), poly A signal sequence (underlined) and termination codons (*) are indicated. An alternate splice site (double underlined) for switching from secretory to membrane form is also noted. Approximately 1.9 kb downstream of CH4 exon lies the 2 membrane exons. The sequence of the first membrane exon is consistent with that previously reported. (2). The sequence of the second exon is deduced from the mouse sequence (4) by virtue of its homology, and bv sequencing our human mu cDNA clone.