[Cloning of a species-specific gene fragment from Cryptosporidium parvum and the development of diagnostic PCR primers].
OBJECTIVE
To develop a pair of diagnostic PCR primers for Cryptosporidium parvum.


METHODS
A species-specific gene fragment of C. parvum was obtained through RAPD analysis. After the fragment was isolated, purified, cloned and sequenced, a pair of primers FF was designed and synthesised based on the sequence. With the primers, the anticipated fragment in size of 603 bp was amplified by PCR from 2 American strains and 4 Chinese strains of C. parvum. The samples of 35 rabbits feces and 55 human feces were detected by PCR with primers FF and 021, the latter was a species-specific diagnostic primer reported by Morgan.


RESULTS
All six strains amplified by the primers FF showed same detection rate with 021. Sensitivity test indicated that DNA of 1 oocyst per gram of feces could be detected by the PCR.


CONCLUSIONS
The primers FF showed high specificity and sensitivity, and can be used for diagnosing Crytosporidium parvum infection.
Tian
Zong-cheng
ZC
Department of Preventive Veterinary Science, the Quartermarster University of PLA, Changchun 130062.
Zhang
Xi-chen
XC
Li
Jian-hua
JH
Yin
Ji-gang
JG
Yang
Ju
J
He
Hong-xuan
HX
D000818:Animals; D002417:Cattle; D002645:Chickens; D003001:Cloning, Molecular; D003457:Cryptosporidiosis / Q000175:diagnosis*; D016785:Cryptosporidium parvum / Q000235:genetics* / Q000302:isolation & purification; D017931:DNA Primers; D016054:DNA, Protozoan / Q000032:analysis*; D004285:Dogs; D004372:Ducks; D005243:Feces / Q000469:parasitology; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D011817:Rabbits; D019105:Random Amplified Polymorphic DNA Technique; D012377:Rodentia; D012680:Sensitivity and Specificity; D013045:Species Specificity
D017931:DNA Primers; D016054:DNA, Protozoan