The invention discloses a gRNA sequence. The sequence is capable of editing
a DNA sequence in the manner of taking a
hepatitis B viral
genome specific locus as a target sequence. The invention also discloses a
CRISPR-SaCas9
system containing the gRNA sequence and a recombinant adeno-associated
virus packaged with the
system. The
system and the packaging
virus show higher HBV
scavenging activity in cells and in transgenic mice body. On the 38th day after twice continuous high
dose injection, the contents of
HBsAg and
HBeAg in experimental group mice serum, compared with the control group, are respectively reduced by 62.96+ / -7.59% and 65.18+ / -3.08%; the HBV
DNA content in the serum, compared with the control group, is reduced by 92.82+ / -3.67%; the liver and other visceral organs of the experimental mice are all free from any
pathologic change, the off-target effect is also not detected and the application prospects of the gRNA sequence and the corresponding
CRISPR-SaCas9 system provided by the invention in preparing the
hepatitis B therapeutics are shown.