Variations in the NSP4 gene of the type 2 porcine reproductive and respiratory syndrome virus isolated in China from 1996 to 2021.

"table 1 the reference sequence of each prrsv nsp4 strain year aera strain genbank accession number 1992 usa atcc vr2332 u87392 1994 usa respprrsmlv af066183 1996 china ch-1a ay032626 1996 china bj-4 af331831 1999 usa mlv respprrs/repro af159149 2001 usa mn184a dq176019 2001 china hb-1(sh)/2002 ay150312 2001 china hb-2(sh)/2002 ay262352 2002 china hb-1/3 9c hq233605 2003 usa ja142 ay424271 2003 china hn1 ay457635 2003 china gs2003 eu880442 2004 china nvsl 97-7895 ay545985 2005 china gd3 gu269541 2006 china ingelvac atp dq988080 2006 china prime pac dq779791 2006 china heb1 ef112447 2006 china cc-1 ef153486 2006 china fz06a mf370557 2006 china tj eu860248 2006 china hub1 ef075945 2006 china hub2 ef112446 2006 china jx143 eu708726 2006 china jxa1 ef112445 2006 china hun4 ef635006 2006 usa mn184c ef488739 2007 china em2007 eu262603 2007 china shh eu106888 2007 china ln eu109502 2007 china hn07-1 kx766378 2007 china gd eu825724 2006 usa mn184b dq176020 2007 china sy0608 eu144079 2007 china pjx143 ef488048 2007 china henan-1 eu200962 2007 china wuh1 eu187484 2008 china xh-gd eu624117 2008 china yn2008 eu880435 2008 china yn9 gu232738 2008 china jxa1-p80 fj548853 2008 china prrsv01 fj175687 2008 china jn-hs hm016158 2008 china gdby1 gq374442 2008 china ch-1r eu807840 2008 usa nadc30 jn654459 2008 usa nadc31 jn660150 2009 china sy0909 hq315837 2009 china zp-1 hm016159 2009 china sx-1 gq857656 2009 china wuh2 eu678352 2009 china jxa1-p120 kc422727 2009 china sd1-100 gq914997 2009 china gs2002 eu880441 2009 china ch2002 eu880438 2009 china ch2003 eu880440 2009 china ch2004 eu880439 2010 china jx jx317649 2010 china qy2010 jq743666 2010 china gx1003 jx912249 2010 china 10fs-gd jx192634 2011 china gm2 jn662424 2011 china yn-2011 jx857698 2011 china hh08 jx679179 2011 china qyyz jq308798 2012 china nt1 kp179402 2012 china fjfs kp998476 2012 china hz-31 kc445138 2012 china sh1211 kf678434 2013 china jl580 kr706343 2013 china bj-f150 kp890342 2013 china henan-a9 kj546412 2013 china fjw05 kp860911 2013 china henan-xinx kf611905 2013 china hljb1 kt351740 2014 china chsx1401 kp861625 2014 china nmg2014 km000066 2014 china gd1404 mf669720 2014 china zjxs1412 mf669722 2014 china tjbd14-1 kp742986 2014 china fj1402 kx169191 2015 china xjzx1 kx689233 2015 china hnyc15 kt945018 2015 china sc-d mf375261 2015 china hen1501 mf766472 2015 china hen1502 mf766473 2015 china sd-a19 mf375260 2015 china gdsg kx621003 2015 china tjnh1501 kx510269 2015 china 15ly02-fj ku215417 2015 china hzl1501 mf669721 2015 china hnjz15 kt945017 2015 china fjz03 kp860909 2016 china gdzs2016 mh046843 2016 china hnhx kx766379 2016 china hen1601 mf766474 2016 china jxwn06 ef641008 2016 china 15ln1 kx815423 2016 china sh/ch/2016 ky495781 2016 china jx/ch/2016 ky495780 2016 china sdbz16-2 mh588710 2017 china sd-yl1712 mt708500 2017 china sd17-36 mh121061 2017 china sd17-38 mh068878 2017 china qhd2 mh167387 2017 china qhd3 mh167388 2017 china jstz1712-12 mk906026 2017 china xj17-5 mk759853 2017 china fjwq16 kx758249 2017 china scn17 mh078490 2017 china sccd17 mg914067 2017 china fjm4 ky412888 2017 china gzgy17 mk144542 2018 china scya18 mk144543 2018 china hbap4-2018 mz579701 2019 china jsyz1909-16 mt780871 2019 china sdrz01 mz322956 2020 china sd-qd-2101 mz172971 2020 china sxsz-2020 mw880772 2020 china js2020 mz342900 2020 china rjxa1-r mt163314 2020 china sccd2020 mw803134 2021 china bj2021 ok095299 2021 china hy21 ol687155 the clustal w method in the megalign function of dnastar package (version 7 0; dnastar madison wi) was used to analyze nsp4 nucleotide sequence similarities and information regarding the reference strains is provided in table 1 ."

"Declarations Conflict of interestThe authors declare that they have no competing interests Ethical approval and consent to participateAll authors read and approved the final manuscript. Consent for publicationNot applicable Conflict of interest The authors declare that they have no competing interests"

"Funding This research was funded by the National Natural Science Foundation of China (31902279, 31902284), Guangdong Science and Technology Program Project (2021A1515012388, 2017A020208079), and the Guangdong Basic and Applied Basic Research Foundation (2021A1515110322)."