Table 1. Analysis of virulence genetic markers in the viral PB2, PB1, PA, M2, NS1, and NS2 proteins in H9N2 isolated from Iraq.

Protein	aa Site	Virulent	A virulent	H9N2	Reference
PB2	627	K	E	E	(Wang et al., 2012)
	147	L	M	V	(Wang et al., 2012)
	250	G	V	V	(Wang et al., 2012)
	504	V	I	V	(Rolling et al., 2009)
	701	N	D	D	(Zhou et al., 2013)
	591	K	Q	P	(Mok et al., 2014)
PB1	317	I	M/V	M	(Chen et al., 2006; Lee et al., 2007)
PA	127	V	I	V	(Lycett et al., 2009)
	672	L	F	L	(Li et al., 2005)
	100	R	V	V	(Otte et al., 2015)
	550	L	I	I	(Rolling et al., 2009)
M2	64	S/A/F	P	S	(Lycett et al., 2009)
	69	P	L	P	(Lycett et al., 2009)
NS1	42	S	A/P	S	(Jiao et al., 2008)
	92	E	D	D	(Lee et al., 2007)
	103	L	F	L	(Dankar et al., 2011)
	106	I	M	M	(Dankar et al., 2011)
	189	N	D/G	D	(Subbarao and Shaw, 2000)
NS2	31	I	M	M	(Subbarao and Shaw, 2000)
	56	Y	H/L	H	(Subbarao and Shaw, 2000)