Fig. 7

Examples of genome browsers. a Screenshot of Ensembl genome browser showing the transcript splicing variants for the gene KCNT1 encoding a potassium channel subunit. Gold-coloured transcripts are those that are found by both manual and computational annotation. Black transcripts are those that have been identified only through manual annotation. Blue transcripts are annotated without a coding sequence (CDS). For example, the red arrow highlights an exon that causes a premature stop codon. This transcript has therefore been identified as being subject to nonsense-mediated decay. b Screenshot of the UCSC genome browser also showing KCNT1. Comparison of, first, the basic GENCODE gene annotation set (generally full-length coding transcripts based on full-length cDNAs) and, second, RefSeq manually curated genes, which generally have fewer transcripts than GENCODE. The red boxes highlight novel transcription start site exons and novel internal exons that are not present in RefSeq