Fig. 2

a Variant position percentages across sequence classes. The ANNOVAR program was used to classify variant positions. Intergenic: variant is in the intergenic region, not included in Upstream or Downstream, Intronic: variant overlaps an intron, Exonic: variant overlaps a coding region, Upstream: variant overlaps 1-Kb region upstream of the transcription start site, Downstream: variant overlaps 1-Kb region downstream of the transcription end site, Splicing: variant is within 2 bp of a splicing junction. The absolute numbers of variants were shown above the bars. Genome percentages of the same classes are shown alongside. b Effects of the Exonic variants. Synonymous : a single nucleotide change that does not cause an amino acid change, Non synonymous : a single nucleotide change that causes an amino acid change, Frameshift insertion/deletion: an insertion or deletion of one or more nucleotides that cause frameshift changes to proteins, Stop gain/loss: a nonsynonymous SNP or indel that leads to the immediate creation/elimination of a stop codon at the variant site, Frameshift substitution: a block substitution (not insertion or deletion) of one or more nucleotides that cause frameshift changes, unknown: unknown function (caused by various errors in the gene structure definition in the database file). Each position can have more than one alternative variant and the effect could be different