ABSTRACT
Fasciola eggs were collected from stool of a woman aged 21 years old in Nghe An province. Miracidium were obtained from these eggs after 20 days culture in the laboratory. A portion of the mitochondrial-encoded nad1 gene from these miracidiums were amplified using polymerase chain reaction (PCR) and comparatively aligned with the known corresponding sequences of Fasciola gigantica taken from cattle in Hoa Binh, Lai Chau, Lang Son, Ninh Binh and international strains (from Korea, Japan and Indonesia). The results showed high similar co-efficient of nucleotide 98-99% and amino acid 95-99%, but lower rate than that of Fasciola hepatica (Australian and American) (90-92%). However, it is suggested that the Vietnamese F.gigantica have had the genetic signs hybridized with F.hepatica