Region _get_gene_range(Tx & tx) {
/**
get the lowest and highest positions of a transcripts coding sequence
*/
int boundary_1 = tx.get_cds_start();
int boundary_2 = tx.get_cds_end();
int start = std::min(boundary_1, boundary_2);
int end = std::max(boundary_1, boundary_2);
return Region {start, end};
}
