Ordaz-Vázquez Anabel, Soberanis-Ramos Orbelin, Cruz-Huerta Edith, Retis-Sanchez-de-la-Barquera Sandra, Chávez-Mazari Bárbara, Gudiño-Enriquez Tomasa, Santacruz-Aguilar Mario, Ponce-De-León-Garduño Alfredo, Sifuentes-Osornio José, Bobadilla-Del-Valle Miriam
Laboratory of Clinical Microbiology, Department of Infectious Diseases, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
Department of Preventive Medicine and Public Health, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Transbound Emerg Dis. 2022 May;69(3):1144-1154. doi: 10.1111/tbed.14074. Epub 2021 Apr 20.
Bovine tuberculosis (bTB) is mainly caused by Mycobacterium bovis. In Mexico, dairy cattle play an important role in the persistence and spread of the bacillus. In order to describe M. bovis genetic diversity, we genotyped a total of 132 strains isolated from slaughtered cattle with bTB suggestive lesions between 2009 and 2010 in Hidalgo, Mexico, using a panel of 9-loci mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTR) and spoligotyping. We found 21 spoligotypes, and 124 isolates were grouped in 13 clusters. The most frequent spoligotypes were SB0121 (49, 37.1%) and SB0673 (27, 20.5%); three new spoligotypes were reported SB02703, SB02704 and SB02705. We observed 37 MIRU-VNTR patterns, 107 isolates were grouped in 12 clusters and 25 isolates were unique. Spoligotypes SB0121, SB0673, SB0140, SB0145 and SB0120 showed marked subdivision applying MIRU-VNTR method; meanwhile, spoligotypes SB0971 and SB0327 showed single MIRU-VNTR profiles. The Hunter-Gaston discriminatory index (HGDI) was 0.88, 0.78 and 0.90 for 9-loci MIRU-VNTR, spoligotyping and both methods, respectively. Additionally, allelic diversity (h) analysis showed high diversity for QUB3232, QUB26 and QUB11b with h = 0.79, 0.66 and 0.63, respectively. Overall, high genetic variability was observed among M. bovis isolates. Thus, the use of 9-loci MIRU-VNTR panel is enough to describe genetic diversity, evolution and distribution of M. bovis. This study supports the use of these tools for subsequent epidemiological studies in high incidence areas.
牛结核病（bTB）主要由牛分枝杆菌引起。在墨西哥，奶牛在该杆菌的持续存在和传播中起着重要作用。为了描述牛分枝杆菌的遗传多样性，我们对2009年至2010年间在墨西哥伊达尔戈从有牛结核病疑似病变的屠宰牛中分离出的132株菌株进行了基因分型，使用了一组9个位点的分枝杆菌散布重复单位 - 可变数目串联重复序列（MIRU - VNTR）和间隔寡核苷酸分型法。我们发现了21种间隔寡核苷酸分型，124株分离株被分为13个簇。最常见的间隔寡核苷酸分型是SB0121（49株，37.1%）和SB0673（27株，20.5%）；报告了三种新的间隔寡核苷酸分型SB02703、SB02704和SB02705。我们观察到37种MIRU - VNTR模式，107株分离株被分为12个簇，25株分离株是独特的。间隔寡核苷酸分型SB0121、SB0673、SB0140、SB0145和SB0120应用MIRU - VNTR方法显示出明显的细分；同时，间隔寡核苷酸分型SB0971和SB0327显示出单一的MIRU - VNTR图谱。9个位点的MIRU - VNTR、间隔寡核苷酸分型以及两种方法的Hunter - Gaston鉴别指数（HGDI）分别为0.88、0.78和0.90。此外，等位基因多样性（h）分析显示，QUB3232、QUB26和QUB11b的多样性较高，h分别为0.79、0.66和0.63。总体而言，在牛分枝杆菌分离株中观察到了高度的遗传变异性。因此，使用9个位点的MIRU - VNTR面板足以描述牛分枝杆菌的遗传多样性、进化和分布。本研究支持在高发病地区后续的流行病学研究中使用这些工具。
