Scale diagram of the genomic and cDNA organization of NDRG1, with an illustration of the HMSNL mutation. a, Genomic organization. The NDRG1 gene consists of 16 exons spanning 60 kb of genomic sequence. A CpG island overlaps with the first exon and the 5′ end of intron 1. A potential promoter with a TATA box, a GC box similar to the N-myc binding region of mouse Ndr1, and a TATA-less enhancer were located 39 bp, 65 bp, and 81 bp upstream, respectively, of the first exon. The 5′ UTR is split between the first two exons. b, cDNA structure. Translation starts from nucleotide position 123. c, HMSNL mutation: C→T substitution at base 564 results in a stop signal (TGA) at codon 148 in exon 7 (R148X). All nucleotide positions are given relative to the published sequence (GenBank accession number D87953).