PCR-RFLP method to detect zoonotic and host-specific Giardia duodenalis assemblages in dog fecal samples.

Giardia duodenalis is a zoonotic protozoan that parasitizes the upper small intestine of human and many mammals including dogs. To develop a restriction fragment length polymorphism (RFLP) method for typing zoonotic (A, B) and host-specific (C, D) assemblages of G. duodenalis from dog, β-giardin gene was amplified with design primer pairs B3 and B4. The PCR products were digested with restriction enzyme Afa I and Msp I; then, PCR-RFLP method was compared with HRM genotyping and sequencing method for G. duodenalis from dog. The results showed that each of assemblages A-D had unique restriction pattern, which was consistent with the predictive results. Among 21 samples tested by PCR-RFLP, 1 human-derived and 8 dog-derived G. duodenalis were identified as assemblage A; 5 dog-derived G. duodenalis as assemblage C; 7 dog-derived G. duodenalis as assemblage D, which were coincided with the HRM genotyping and sequencing results. It is concluded that the PCR-RFLP is quick, easy, and accurate method for the sequence typing of G. duodenalis zoonotic and specific assemblages from dogs.