简介：BeijinghasbeenoneoftheepicentersattackedmostseverelybytheSARS-CoV(severeacuterespiratorysyndrome-associatedcoronavirus)sincethefirstpatientwasdiagnosedinoneofthecity'shospitals.WenowreportcompletegenomesequencesoftheBJGroup,includingfourisolates(IsolatesBJ01,BJ02,BJ03,andBJ04)oftheSARS-CoV.ItisremarkablethatallmembersoftheBJGroupshareacommonhaplotype,consistingofsevenlocithatdifferentiatethegroupfromotherisolatespublishedtodate.Among42substitutionsuniquelyidentifledfromtheBJgroup,32arenon-synonymouschangesattheaminoacidlevel.Rootedphylogenetictrees,proposedonthebasisofhaplotypesandothersequencevariationsofSARS-CoVisolatesfromCanada,USA,Singapore,andChina,gaverisetodifferentparadigmsbutpositionedtheBJGroup,togetherwiththenewlydiscoveredGD01(GD-Ins29)inthesameclade,followedbytheH-UGroup(fromHongKongtoUSA)andtheH-TGroup(fromHongKongtoToronto),leavingtheSPGroup(Singapore)moredistant.ThisresultappearstosuggestapossibletransmissionpathfromGuangdongtoBeijing/HongKong,thentoothercountriesandregions.