Molecular Identification of Giardia duodenalis Parasite Isolates from Human by Polymerase Chain Reaction – Restriction Fragment Length Polymorphism Technique (PCR-RFLP) in Baghdad Province

Abstract

The present study was designed to determine the genotypes of Giardia duodenalis isolatesfrom human by using polymerase chain reaction – restriction fragment length polymorphismtechnique (PCR-RFLP) technique, by amplification of glutamate dehydrogenase (gdh) gene toprovide information about the genetic diversity and their epidemiological and clinicalcharacteristics in Baghdad province. Thirty isolates from children (1-12 years old) wereprocessed for (PCR-RFLP). Data corresponding to demographic, social and environmentalvariables and presence or absence of symptoms were collected. The glutamate dehydrogenase(gdh) gene was amplified by using specific primers (GDHiF and GDHiR), the PCRamplification was observed in 17/30 (56.6%) of the fecal samples, among these 5/17 (29.4%)samples belonged to genotype A and 12/17 (70.5%) samples belonged to genotype B. Geneticsubgenotypes identified from human fecal samples revealed that, 5/17 (29.4%) weresubgenotype AΙΙ, 9/17 (52.9%) subgenotype BΙΙΙ, and 3/17 (17.6%) subgenotype BΙV.Genotype B was detected in children with severe symptomatic giardiasis and many of themhad diarrhea while, subgenotype AΙΙ was detected in children with mild symptomaticgiardiasis and without diarrhoea.