The exon-intron structure and mRNA sequence of human ZAR2 gene. (A) Cartoon showing the exon-intron structure of human ZAR2 gene. The first exon of ZAR2 overlaps with the exon 1 of the BRCA2 gene (not drawn to the scale). (B) Nucleotide sequence of human ZAR2 mature mRNA. The 5'-UTR sequence was experimentally determined (see text for details). The putative protein coding sequence (ORF) is shown in blue and highlighted in gray. The upstream AUG (uAUG) codons at the 5'-UTR are highlighted: out-of-frame uAUGs are in yellow shades; in-frame uAUGs are in green shades. The 5'-UTR sequence overlapping with BRCA2 mRNA sequences are shaded yellow. Rest of the 5'-UTR sequence of ZAR2 mRNA is derived from the newly identified exon 1 and is shown in red.