Feline Immunodeficiency Virus (FIV) is the most prominent retrovirus in cats. Molecular studies on FIV are of great importance to enable further studies, for example, understanding the pathogenesis and developing improved vaccines. We aimed to elucidate the molecular status of FIV and provide a detailed characterization of FIV in Turkey because at present there is very limited information available in the literature. We also evaluated a potential link between clinical symptoms and FIV subtypes according to results obtained from molecular tests.

Whole blood was collected from 200 client-owned domestic cats and molecular diagnosis and characterization was performed. The env, gag and vif gene regions were amplified and sequenced for phylogenetic analysis. We obtained specific amplicons based on bothenvand gag for FIV in 21 cats; only 2 of the 21 positive samples could also be characterized based on the vif gene region. Separate clusters were identified according to previously determined genotyping strategies; however, they were observed in FIV subtype B. The molecular findings of some individual cats were evaluated in conjunction with their clinical symptoms in an attempt to determine potential relationships between the genetic characteristics of FIV and symptoms of disease. As a result, overexpression of the vif gene could be important in leading to serious clinical symptoms.

Our results emphasize the necessity of considering FIV in diagnosis and performing the neccesary diagnostics to confirm or rule out FIV infection. The molecular dynamics of FIV should be periodically updated by further analyses to establish a successful prevention strategy.

猫免疫缺陷病毒（FIV）是猫中最突出的逆转录病毒。有关FIV的分子研究对于开展进一步的研究非常重要，例如，了解其发病机理和开发改良的疫苗。我们旨在阐明FIV的分子状态并提供FIV在土耳其的详细表征，因为目前文献中提供的信息非常有限。我们还根据分子测试获得的结果评估了临床症状与FIV亚型之间的潜在联系。

从200只客户拥有的家猫中采集全血，并进行分子诊断和表征。该ENV，GAG和VIF基因区域进行扩增，测序系统发育分析。我们基于env和gag获得了特定的扩增子用于21只猫的FIV；根据vif基因区域，也只能表征21个阳性样品中的2个。根据先前确定的基因分型策略确定了单独的簇；但是，它们是在FIV亚型B中观察到的。结合某些猫的临床症状对其分子发现进行了评估，以试图确定FIV遗传特征与疾病症状之间的潜在关系。结果，vif基因的过度表达对于导致严重的临床症状可能很重要。

我们的结果强调在诊断中考虑FIV并进行必要的诊断以确认或排除FIV感染的必要性。应通过进一步分析定期更新FIV的分子动力学，以建立成功的预防策略。