Type of genetic engineering
Gene knockout, gene knockin, gene overexpression can be further categorized as below.
| Type | Segment type | Characterization | Technology options |
| Gene knockout | Knockout, KO | Systemic gene fragment knock out | ESC Targeting， CRISPR |
| Conditional knockout, CKO | Gene fragment knock out in specific tissues or cells |
ESC Targeting， CRISPR | |
| KO-first | Mating with Cre mouse to obtain reporter and knockout mice; mating with Flp mouse to obtain flox mice | ESC Targeting， CRISPR | |
| Gene knock-in | Constitutive mutation | Systemic introduction of genetic mutation | ESC Targeting， CRISPR |
| Conditional mutation | Mutation introduced in specific tissues or cells |
ESC Targeting， CRISPR | |
| Knockin | Exclusive expression of exogenous genes | ESC Targeting， CRISPR | |
| Co-expression | Exogenous gene is expressed without affecting the endogenous gene expression | ESC Targeting， CRISPR | |
| Humanization | The mouse endogenous gene was replaced with a human homologous gene | ESC Targeting， CRISPR | |
| Gene overexpression | Random transgenesis | Gene of interest randomly integrated into the mouse genome | Pronuclear injection or Lentivirus infection |
| PiggyBAC transgenesis | Gene of interest integrated into the transposase recognition sites of mouse genome | Piggybac Transgene | |
| Site-specific knockin | Gene of interest specifically incorporated into safe harbor sites such as Rosa26 or H11 | ESC Targeting， CRISPR |
