seq_region_start|end could have returned undef inappropraitely when one (but not both) of the features end|start was undefined
seq_region_start|end could have returned undef inappropraitely when one (but not both) of the features end|start was undefined

willmclaren/ensembl,muffato/ensembl,danstaines/ensembl,muffato/ensembl,at7/ensembl,mjg17/ensembl,Ensembl/ensembl,willmclaren/ensembl,Ensembl/ensembl,Ensembl/ensembl,at7/ensembl,danstaines/ensembl,james-monkeyshines/ensembl,james-monkeyshines/ensembl,james-monkeyshines/ensembl,at7/ensembl,james-monkeyshines/ensembl,mjg17/ensembl,at7/ensembl,Ensembl/ensembl,muffato/ensembl,muffato/ensembl,mjg17/ensembl,danstaines/ensembl,mjg17/ensembl