Biomaterial Database

Genotyping of varicella-zoster virus and the discrimination of Oka vaccine strains by TaqMan real-time PCR. 2006

S P Parker, and M Quinlivan, and Y Taha, and J Breuer

Skin Virus Laboratory, Centre for Infectious Disease, Institute of Cell and Molecular Science, Barts and the London school of Medicine and Dentistry, 4 Newark St., London E1 2AT, England.

Single nucleotide polymorphisms (SNPs) in five genes have been used to identify four major subtypes of wild-type varicella-zoster virus (VZV) A, B, C, and J. Additional SNPs, located in the IE62 major transactivating gene can be used to differentiate the Oka vaccine strain (vOka) from wild-type VZV. Primer-probe sets for the detection of the five polymorphic loci were designed by Applied Biosystems for the ABI 7900HT platform. Probes for each allele were labeled with VIC or 6-carboxyfluorescein fluorogenic markers. Each primer-probe set was validated to establish assay sensitivity and specificity using VZV DNA of predetermined copy number and genotype. Further evaluation was carried out using DNA samples from the vesicle fluid or skin swab of the rash of adult patients with herpes zoster or rashes due to vOka. Assay sensitivity ranged from 10 and 10(8) copies/ml of VZV DNA (equivalent to 2 to 20 copies per reaction). Statistical analyses showed that for each genotype, a set of two probes clearly differentiated the nucleotide present (allele) at that locus (P < 0.0001). It was possible to determine the genotype of wild-type VZV using one of four SNP assays and also to differentiate wild type from vOka using a single SNP assay. The assay can be used for diagnostic and epidemiological studies of VZV, including the differentiation of vOka from wild-type strains, investigation of breakthrough infections, and varicella outbreaks following immunization.

UI	MeSH Term	Description	Entries
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D012680	Sensitivity and Specificity	Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)	Specificity,Sensitivity,Specificity and Sensitivity
D014645	Herpesvirus 3, Human	The type species of VARICELLOVIRUS causing CHICKENPOX (varicella) and HERPES ZOSTER (shingles) in humans.	Chickenpox Virus,Herpes zoster Virus,Ocular Herpes zoster Virus,VZ Virus,Varicella-Zoster Virus,HHV-3,Herpesvirus 3 (alpha), Human,Herpesvirus Varicellae,Human Herpesvirus 3,Chickenpox Viruses,Herpes zoster Viruses,VZ Viruses,Varicella Zoster Virus,Varicella-Zoster Viruses,Varicellae, Herpesvirus
D016133	Polymerase Chain Reaction	In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.	Anchored PCR,Inverse PCR,Nested PCR,PCR,Anchored Polymerase Chain Reaction,Inverse Polymerase Chain Reaction,Nested Polymerase Chain Reaction,PCR, Anchored,PCR, Inverse,PCR, Nested,Polymerase Chain Reactions,Reaction, Polymerase Chain,Reactions, Polymerase Chain
D016366	Open Reading Frames	A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).	ORFs,Protein Coding Region,Small Open Reading Frame,Small Open Reading Frames,sORF,Unassigned Reading Frame,Unassigned Reading Frames,Unidentified Reading Frame,Coding Region, Protein,Frame, Unidentified Reading,ORF,Open Reading Frame,Protein Coding Regions,Reading Frame, Open,Reading Frame, Unassigned,Reading Frame, Unidentified,Region, Protein Coding,Unidentified Reading Frames
D019433	Chickenpox Vaccine	A live, attenuated varicella virus vaccine used for immunization against chickenpox. It is recommended for children between the ages of 12 months and 13 years.	Oka Varicella Vaccine,Varicella Vaccine,Varivax,Vaccine, Chickenpox,Vaccine, Oka Varicella,Vaccine, Varicella,Varicella Vaccine, Oka
D020641	Polymorphism, Single Nucleotide	A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.	SNPs,Single Nucleotide Polymorphism,Nucleotide Polymorphism, Single,Nucleotide Polymorphisms, Single,Polymorphisms, Single Nucleotide,Single Nucleotide Polymorphisms