Patent ID: 6093535
Filing Date: 2000-07-25
Classification: A61K,C07K,C12N,C12Q

Abstract:
A method for identifying the attenuated varicella virus Oka strain or a strain derived therefrom which functions as an effective component of an attenuated variceila vaccine, which comprises:analyzing a genomic DNA and DNA fragments thereof present in a sample of varicella virus;determining whether the analyzed genomic DNA and DNA fragments thereof of said sample of varicella virus satisfy eight characteristics (A1) to (A8) defined below; andidentifying said sample of varicella virus as the attenuated varicella virus Oka strain or a strain derived therefrom which functions as an effective component of an attenuated varicella live vaccine when said sample satisfies all of the following eight characteristics (A1) to (A8):(A1) the size of the K fragment obtained by digesting the varicella virus genomic DNA with the restriction enzyme HpaI is 3231 bp;(A2) the size of the P fragment obtained by digesting the varicella virus genomic DNA with the restriction enzyme EcoRI is 1749 bp;(A3) when a DNA fragment which is amplified from the varicella virus genomic DNA by PCR using the PCR primer 1 (SEQ ID NO. 3) and the PCR primer 3 (SEQ ID NO. 5) is treated with the restriction enzyme AccIII, the DNA fragment is cleaved into two parts having sizes of 1208 bp and 556 bp, respectively;(A4) a DNA fragment which is amplified from the varicella virus genomic DNA by PCR using the PCR primer 2 (SEQ ID NO. 4) and the PCR primer 3 (SEQ ID NO. 5) has a size of 487 bp;(A5) the varicella virus genomic DNA and the attentuated varicella virus Oka strain genomic DNA exhibit substantially the same electrophoretic mobility with respect to a DNA fragment determined by PCR-SSCP wherein the PCR primer 2 (SEQ ID NO. 4) and the PCR primer 3 (SEQ ID NO. 5) are used in the PCR of said PCR-SSCP;(A6) a DNA fragment which is amplified from the varicella virus genomic DNA by PCR using the PCR primer PS1 (SEQ ID NO. 7) and the PCR primer PS2 (SEQ ID NO. 8) lacks a restriction enzyme PstI cleavage site;(A7) the homology between the 162 amino acid sequence coded by the 487 bp DNA fragment amplified from the varicella virus genomic DNA by PCR using the PCR primer 2 (SEQ ID NO. 4) and the PCR primer 3 (SEQ ID NO. 5), and the 162 amino acid sequence of SEQ ID NO. 1 is 98 to 100%, wherein the percent homology is represented by the following formula (1):{(162-n)/162.times.100 (1)wherein n represents the number of different amino acids; and(A8) the homology between the 560 amino acid sequence coded by the entire coding region of Gene14, and the 560 amino acid sequence of SEQ ID NO. 2 is 99 to 100%, wherein the percent homology is represented by the following formula (2):{(560-n)/560}.times.100 (2)wherein n represents the number of different amino acids.