Primer probe for detection, primer probe set, and application thereof

A primer probe set for PCR detection, comprising a first primer, a probe (P), and a second primer;

• and characterized in that,
• the first primer comprises a target sequence binding region 1, which is a sequence that can specifically bind with a target sequence in a paired manner;
• the probe (P) is a sequence that does not bind with any target sequence in a paired manner, and comprises a probe signal detection region (H);
• and the probe (P) is labeled with a detection label;
• the second primer comprises a primer signal detection region (h) and a target sequence binding region 2;
• wherein, the target sequence binding region 2 is a sequence that can specifically bind with the target sequence in a paired manner, the primer signal detection region (h) is a sequence that does not bind with any target sequence in a paired manner, and a complementary sequence (h′) of the primer signal detection region (h) specifically binds with the probe signal detection region (H) of the probe (P) in a paired manner;
• and the target sequence binding region 2 is located at 3′ end of the primer signal detection region (h);
• the first primer and the second primer specifically bind with the target respectively to produce a pre-amplification product, and the pre-amplification product contains one single-stranded pre-amplification product having the complementary sequence (h′) of the primer signal detection region (h), the complementary sequence (h′) in the single-stranded pre-amplification product specifically binds with the probe (P) and extends by ≥0 bases to form a double-stranded product, and the formation of the double-stranded product causes the probe to produce a detectable signal change.