DNA sequence analysis of the C/EBPϵ gene in the SGD patient. (A) Genomic DNA isolated from a healthy individual (top panel, control) and from the SGD patient (bottom panel) was PCR amplified and sequenced using oligomers designed to capture the C/EBPϵ exons and intron-exon boundaries. The red arrow in the bottom panel indicates the heterozygous mutation in the SGD patient. (B) The genomic organization of the C/EBPϵ locus is indicated showing 3 exons (Ex 1, 2, and 3), 2 promoters (Pα and Pβ), 3 alternate translational start sites (ATG), and the highly conserved basic leucine zipper region (B-zip). (C) Amino acid sequence of the C/EBPϵ B-zip region. The heterozygous valine to alanine substitution in the SGD patient is indicated at position 218 in the basic region, which is underlined. The relevant leucine moieties are also underlined.