Detection Of Multiple Genetic Variants Of Btv Serotype-1 Originated From Different Geographical Regions In India

Bluetongue (BT) is an economically important viral disease of sheep and goat in India causing substantial morbidity and mortality. In the present study, four BTV-1 isolates of Andhra Pradesh and one from Utter Pradesh adapted in BHK-21 cell line were used to find the genetic variations. All the samples were confirmed as bluetongue virus (BTV) based on characteristics cytopathetic effect in BHK-21 cell line, visualization of ten segmented dsRNA genome in RNA-PAGE and 366 bp amplicon size with group specific ns1 gene RT-PCR. All the five isolates were confirmed as BTV serotype 1 based on segment 2 (vp2 gene) specific RT-PCR. Although, all the isolates were BTV serotype 1, significant genomic diversity in migration patterns of ten RNA segments was observed based on RNA-PAGE analysis. Five electropherotypic patterns were reported among BTV-1 isolates belonging to various geographical regions in India. These observations indicated occurrence of great genomic diversity among Indian BTV-1 isolates. These variations are significantly important and should be taken into account along with serotypes for developing future vaccination strategies.