Table 1.

Number of miRNA and host genes (Ensembl, release 77)

	Pig			Human			Mouse
	N	%	%	N	%	%	N	%	%
miRNA total	877	100.0		4272	100.0		2009	100.0
Intergenic	587	66.9		2132	49.9		900	44.8
Intragenic	290	33.1	100.0	2140	50.1	100.0	1109	55.2	100.0
Host strand	186		64.1	1482		69.3	825		74.4
Intron	166		57.2	1282		59.5	710		64.0
Exon	20		6.9	200		9.3	115		10.4
Opposite strand	95		32.8	550		25.7	244		22.0
Intron	71		24.5	485		22.7	197		17.8
Exon	24		8.3	65		3	47		4.2
With multiple hosts	9		3.1	108		5	40		3.6
Hosts total	272	100.0		1887	100.0		930	100.0
miRNA strand	173	63.6	100.0	1201	63.6	100.0	646	69.5	100.0
With intronic miRNA	155		89.6	1011		84.2	540		83.6
With exonic miRNA	18			190			106
Opposite strand	82	30.1	100.0	449	23.8	100.0	216	23.2	100.0
With intronic miRNA	59		72.0	385		85.7	175		81.0
With exonic miRNA	23			64			41
With multiple miRNAs	17	6.3		237	12.6		68	7.3