18 The bovine paratuberculosis (PTB), a contagious fatal disease also known as Johne’s disease, is caused by an acid fast bacteria Mycobacterium avium subspecies paratuberculosis (MAP). Paratuberculosis is now-a- days viewed as one of the most important and wide spread bacterial diseases of ruminants. Cattle less than 6 months of age are most susceptible, and it was estimated that approximately one-third of calves may develop infection with a single exposure. In India, paratuberculosis is in endemic form (Tripathi et al. 2007) and it has zoonotic potential. High prevalence of paratuberculosis was reported in domestic livestock using indigenous, sensitive and MAP specific test in north India. Sero-prevalence of bovines PTB was 29.0% (28.6% in buffalo and 29.8% in cattle) in north India. In Uttar Pradesh and Punjab, seroprevalence of bovine PTB was 32.9 % (31.9% in buffalo and 37.6% in cattle) and 25 % (23.3% in buffalo and 26.9% in cattle), respectively. Susceptibility to MAP infection is heritable Present address: 1,8-12 Research Scholar (drramjivet @gmail.com, tarun.vets88@gmail.com, reddishvet@gmail.com, abhaladhare@gmail.com, dr.omprakash0511@gmail.com, drbaqirvet@gmail.com), 4-6 Scientist (arvind2002@gmail.com, vetamitchandan07@gmail.com, anuj_vet99@rediffmail.com), Animal Genetics; 3,7 Senior Scientist (ranvir@ivri.res.in, subkum@gmail.com); 13 Head (ds7758@yahoo.co.in), Animal Genetics. 2 Principal Scientist (sharmaak62@yahoo.co.in), IVRI, Mukteshwar. Indian Journal of Animal Sciences 84 (5): 490–493, May 2014/Article An association study of SNPs with susceptibility to bovine paratuberculosis infection in cattle RAMJI YADAV 1 , A K SHARMA 2 , RANVIR SINGH 3 , ARWIND SONWANE 4 , AMIT KUMAR 5 , ANUJ CHAUHAN 6 , SUBODH KUMAR 7 , TARUN KUMAR 8 , RENJITH R 9 , ASHISH BHALADHARE 10 , OM PRAKASH 11 , MOHD BAQIR 12 and DEEPAK SHARMA 13 Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh 243 122 India Received: 11 December 2013; Accepted: 18 January 2014 ABSTRACT The study was conducted to identify SNPs of quantitative trait loci (QTL) associated with susceptibility to Mycobacterium avium ssp. paratuberculosis (MAP) infection in cattle. Total 20 SNPs from the cattle QTL database were selected on the basis of the potential role in Mycobacterium susceptibility and a case: control association study was conducted in cattle. Out of 20 SNPs total 17 SNPs were polymorphic and 3 were monomorphic in population. The SNP (rs41945014) was significantly associated with MAP and revealed that ODDs of GG and GT genotypes verses TT genotype were 1.22 (0.33–4.49; 95% CI) and 3.37 (1.23–9.23; 95% CI), respectively. The proportion of GG and GT genotypes were significantly higher in bovine paratuberculosis positive animals suggested that selection against these 2 genotypes may confer resistance against bovine paratuberculosis. The all other 16 polymorphic SNPs of the present investigation were not differing significantly in case-control animals. Key word: Cattle, MAP, Paratuberculosis, Quantitative trait loci, SNP with heritability estimates ranging from 0.06 to 0.102 (Gonda et al. 2006). These studies provided evidence for the existence of important genetic variation in susceptibility to paratuberculosis. Some reports are available about association study of bovine paratuberculosis with candidate gene polymorphism (Ruiz et al. 2007, Settle et al. 2009, Pinedo et al. 2009, Pant et al. 2010, Koets et al. 2010). But till date in India no report is available on candidate gene polymorphism with paratuberculosis infection in cattle. Keeping in view above facts the present study was proposed by selecting 20 SNPs for finding their association with MAP infection in cattle. MATERIALS AND METHODS A case-control resource panel for bovine paratuberculosis was developed at the animal genetics division under the divisional project —Genetic Predisposition to host resistance against Bovine Paratuberculosis in cattle— to develop this resource panel more than 300 cattle’s were screened for presence of bovine paratuberculosis. The Johnin PPD test and unabsorbed indirect ELISA were used for diagnosis of cattle infected with paratuberculosis. Bovine paratuberculosis infection was screened by using Johnin PPD test. The test involved injecting 0.1 ml of Johnin PPD intradermal into cervical region of the animal and the subsequently detection of swelling (delayed hypersensitivity) at the site of injection after 72 h. The