Institute of Agrobiotechnology and Molecular Biology (IABIMO)-CONICET, INTA De Los Reseros y Las Cabañas S/N, Hurlingham, Buenos Aires, Argentina.
Institute of Experimental Medicine (IMEX)-CONICET, National Academy of Medicine, Pacheco de Melo, Buenos Aires, Argentina.
Int J Mycobacteriol. 2021 Jan-Mar;10(1):51-59. doi: 10.4103/ijmy.ijmy_229_20.
Paratuberculosis is an enteric disease caused by Mycobacterium avium sp. paratuberculosis (MAP) that affects mainly ruminant producing losses to the livestock industry. Many molecular epidemiological methods have been used to discriminate MAP isolates.
The aim of this study was to describe the genetic diversity of the Argentinean MAP isolates using a combination of two molecular systems, the mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) ("automated and "non-automated") and the multi-locus short-sequence repeat (MLSSR) system.
Thirty-two isolates were identified as MAP of C type by IS900 polymerase chain reaction (PCA) and IS1311 PCA-restriction enzyme analysis. The main patterns found by both MIRU-VNTR systems were INMV1 (54.5%), INMV2 (24.2%) and INMV11 (9.1%). The INMV5, INMV8 and INMV16 were represented with one isolate each (3.0%). Only 4 MIRU-VNTR loci were polymorphic.
Those isolates sharing the same INMV patterns were analyzed by MLSSR, being locus 2 the most polymorphic one showing isolates with 9, 10, 11, and more than 11 "G" repeats. Besides, the global discriminatory power among isolates could be increased using both techniques. Based on these results, a short version of the "automated" MIRU-VNTR could be used as a screening tool to group isolates genetically related and subsequently perform the SSR using locus 2 on those isolates sharing the same INMV pattern.
副结核病是一种由鸟分枝杆菌副结核亚种（MAP）引起的肠道疾病，主要影响反刍动物，给畜牧业造成损失。许多分子流行病学方法已被用于区分 MAP 分离株。
本研究旨在使用两种分子系统（分枝杆菌间隔重复单元-可变数串联重复（MIRU-VNTR）（“自动”和“非自动”）和多位点短重复序列（MLSSR）系统）组合来描述阿根廷 MAP 分离株的遗传多样性。
通过 IS900 聚合酶链反应（PCA）和 IS1311 PCA-限制性内切酶分析，32 株被鉴定为 C 型 MAP。两种 MIRU-VNTR 系统发现的主要模式为 INMV1（54.5%）、INMV2（24.2%）和 INMV11（9.1%）。INMV5、INMV8 和 INMV16 各代表一个分离株（3.0%）。只有 4 个 MIRU-VNTR 位点具有多态性。
具有相同 INMV 模式的分离株通过 MLSSR 进行分析，第 2 个位点最具多态性，显示出具有 9、10、11 个和 11 个以上“G”重复的分离株。此外，使用这两种技术可以提高分离株之间的全球区分能力。基于这些结果，可以使用简化的“自动”MIRU-VNTR 作为筛选工具，将遗传上相关的分离株分组，然后对具有相同 INMV 模式的分离株使用第 2 个位点进行 SSR。
