Twenty-eight isolates of E. granulosus, collected
from humans at surgery, and a range of intermediate hosts, including
sheep, cattle and camels from abattoirs in North and South Xinjiang
Uygur Autonomous Region, People's Republic of
China, were analysed for DNA sequence variation within regions of
the mitochondrial cytochrome c oxidase I (COI) and
NADH dehydrogenase subunit I (NDI) genes. The isolates were
categorized into 2 distinct and uniform genotypic
groupings, based on the sequences obtained, and the data clearly
indicated that the camel/dog strain (G6 genotype) of
E. granulosus as well as the cosmopolitan, common sheep strain
(G1 genotype) occur in north Xinjiang. The presence of
the camel strain has thus been confirmed in Xinjiang but it is
evident from this and a previous molecular genetic survey
of E. granulosus isolates from north-western China that the
common sheep strain is the most predominant in the region.
From the public health perspective, the majority of infected livestock
will act as reservoirs of human infection there.
During the course of the study, a polymerase chain reaction
(PCR)-restriction fragment length polymorphism (RFLP)
assay, based on the NDI sequence variation, was developed that
allows rapid discrimination of the G1 and G6 genotypes.