Genomic organization of CLCN5 5′UTR region. The CLCN5 5’ UTR region consists of 8 different 5’ alternatively used exons, some of this, remains untranslated. As a result of 5’ alternative splicing (represented by two vertical bars) in exons II and 1b, 11 different mRNAs are generated. Transcription initiates from three different start sites (represented by an arrow) and there are three translation start sites (represented by an inverted triangle). Coloured boxes represent exons and the connecting lines between boxes the introns.