我国部分地区ＮＤＶ的分子流行病学研究

本研究根据新城疫病毒（ＮＤＶ）Ｆ基因编码区１－３７４位核苷酸序列计算其遗传距离并给出了ＮＤＶ的系统发育进化树，将６８株ＮＤＶ分为９个基因型（３０株为国内分离株），其中Ⅰ－Ⅵ是早已存在的老基因型，Ⅶ、Ⅷ、Ⅸ为新发现的基因型，特别是Ⅸ为我国特有的基因型（Ｆ４８ＥＯ、Ｍ３、ＨＬＪ－３、ＨeB-1P和ＮＭ－５）。１９９７－１９９９年我国云南、广西、甘肃、陕西、新疆等地分离的ＹＮ－１Ｐ、ＧＸ－３、Ｈ１、Ｈ２、Ｐ１、ＧＸ－１、ＧＸ－２、ＧＳ－３、ＳＨＸ－２、ＳＨＸ－３、ＳＨＸ－６、ＳＨＸ－７、ＸＪ－２和１９９１年分离的ＨuB-1均属于Ⅶ基因型，该基因型的病毒是９０年以来引起新城疫发生的主要病原。根据遗传距离和分离年代可将此基因型进一步划分为５个基因亚型，分别是Ⅶa、Ⅶb、Ⅶc、Ⅶd和Ⅶe。此外ＨuN-1/98、HLJ-4/95和ＨeH-1P属一个老的基因Ⅵ，１９７９－１９８５年分离自青海的ＱＨ－１、ＱＨ－２、ＱＨ－４属于一个新的基因型－Ⅷ型。可见在我国新城疫的流行是极其复杂的，既有老基因型的危害（Ⅰ－Ⅵ），又有新基因型（Ⅶ）的流行，更有我国独特Ⅷ和Ⅸ基因潜伏。

Molecular Epidemiology ofNewcastle Disease Virus Isolates from Part Region of China

We calculate amino acid genetic distance in 1-374bp of 68 Newcastle disease virus(NDV)isolates(30 isolates are from China)F protein coding region by Jotun Hein method,constructed the phylogenetic tree by the DNA star software.All analyzed NDV strains were divided into nine genotypes,and suggested that there is a novel genotype of NDV in China,which is phylogenetically distinct from all other genotypes defined so far.These strains circulated from 1940's up to now,spanned about 50 years,and were found in China only.We denominated it group IX.Strains from pigeon belonged to group VI,whose prototype virus is a PPMV-1 from pigeon early;maybe this type has some host specificity.NDV strains YN-1P,GX-3,H1,H2,P1,GX-1,GX-2,GS-2,GS-3,SHX-2,SHX-3,SHX-6,SHX-7,XJ-2，and HuB-1 isolated in 1991～1999 are classified into group Ⅶ,and related to NDV strains that circulated in chicken in Southern Africa,and Taiwan in 1990's.Isolates QH-1,QH-2 and QH-4 from Qinhai province of China and those from Southern Africa consist a new genotype Ⅷ.All the results showed that NDV circulated in our country are regional in some extent,and also many strains oversea are imported.So it is very complicated especially in regard of different birds species.On the other hand,although NDV is steadily inherited,it is varied actually and maybe one reason of ND's prevailing.