Patent ID: 8133989

Claim:
A composition useful for the production of two or more copies of a hepatitis B virus (HBV) nucleic acid sequence comprising (i) a first primer comprising at least two segments: (A) a first segment (i) being substantially complementary to a first portion of said HBV nucleic acid sequence and (ii) capable of template dependent extension such that a first primer extension product is produced when said HBV nucleic acid sequence is used as a template; and (B) a second segment being (i) substantially non-identical and substantially non-complementary to said first segment, and (ii) substantially identical to a second portion of said hepatitis B virus (HBV) nucleic acid sequence, such that said second segment of said first primer is capable of hybridizing to said first primer extension product and (ii) a second primer comprising two regions: (A) a first region (1) being sufficiently complementary to a first portion of said first primer extension product to hybridize thereto, and (2) capable of template-dependent extension to produce a second primer extension product when said first primer extension product is used as a template; and (B) a second region being (1) substantially non-identical and substantially non-complementary to said first region, and (2) substantially identical to a second portion of said first primer extension product, such that said second region is capable of hybridizing to the complement of said second portion of said first primer extension product formed by extension of the first region with said first primer extension product as a template, thereby providing for binding of a second copy of said second primer to said first primer extension product under isothermal or limited cycling conditions.