MT	Cufflinks	exon	1	16720	0	+	.	gene_id "mask_1"; transcript_id "mask_id1/+";
MT	Cufflinks	exon	1	16720	0	-	.	gene_id "mask_1"; transcript_id "mask_id1/-";
GL000220.1	Cufflinks	exon	95627	161949	0	+	.	gene_id "mask_2"; transcript_id "mask_id2/+";
GL000220.1	Cufflinks	exon	95627	161949	0	-	.	gene_id "mask_2"; transcript_id "mask_id2/-";