GENOME ANALYSIS OF NORTH AMERICAN SMALL RUMINANT LENTIVIRUSES BY POLYMERASE CHAIN REACTION AND RESTRICTION ENZYME ANALYSIS

Authors: ROSATI SERGIO - UNIV. OF TURIN, ITALY; Kwang, Hwei Sing; Keen, James

Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/14/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary: Two so-called slow viruses (ovine and caprine lentiviruses) cause persistent infection and chronic debilitating diseases in sheep and goats. These two viruses are closely related and show immunologic cross-reaction. Thus, proteins (antigens) made from the sheep virus grown in a tissue culture can be used to detect antibodies in both sheep and goats. Little information is available on the genetic variation among different isolates of these viruses. In this report, we studied three gene fragments which produced three distinct proteins from nine North American isolates of the sheep virus. We found significant genetic heterogeneity among the nine strains studied. This heterogeneity among the viral strains may make it difficult to develop tests for the various strains of these viruses using DNA tests and may explain some of the variation in the severity of clinical diseases associated with these viruses.

Technical Abstract: The polymerase chain reaction was used to amplify eight ovine and one caprine lentivirus isolates. Three sets of primers were used to amplify gene fragments encoded p16, p25, and N'-gp40. Various degrees of amplification efficiency were observed and different stringent conditions of hybridization were used. The p25 primers detected all strains, the gp40 primers detected one ovine and the caprine strain, and the p16-primers detected only one ovine strain. Restriction endonuclease analysis of five amplified products encoded p25 and two encoded N'-gp40 revealed extensive heterogeneity among North American isolates.