Lack of association between polymorphic copies of endogenous Jaagsiekte sheep retrovirus (enJSRVs) and Ovine Pulmonary Adenocarcinoma

•The association between the presence of enJSRVs and OPA disease was studied.•enJSRVs zygosity was assessed, being the youngest enJSRVs heterozygotes.•The provirus enJSRV-16 has suffered a recent proliferation in Latxa sheep breed.•Polymorphic enJSRVs do not appear to be associated with OPA development.