['chr1', 'chr2', 'chr3', 'chr4', 'chr5', 'chr6', 'chr7', 'chr8', 'chr9', 'chr10',
'chr11', 'chr12', 'chr13', 'chr14', 'chr15', 'chr16', 'chr17', 'chr18', 'chr19',
'chr20', 'chr21', 'chr22']
independent of the species, not all species have those chromosomes (for example mouse only has up to chr19).