Stable clustered regularly interspaced short palindromic repeats-based genome editing in Harmonia axyridis

Harmonia axyridis (Pallas), commonly known as the Asian lady beetle, is a native insect species of Asia that has been intentionally introduced to various regions for biocontrol purposes. However, its widespread presence beyond its original release sites suggests a high degree of invasiveness. In this study, we utilized the CRISPR-Cas9 approach to achieve precise genome editing in H. axyridis. Specifically, we targeted two genes in H. axyridis, laccase2 and scarlet, knockdown of which orthologues in other insects showed visible phenotypic changes. The knockout laccase2 resulted not only in an early-detectable phenotype but also in lethality. However, we successfully established a viable and genetically stable mutant colony by disrupting the scarlet gene, resulting in beetles with white eyes. Our findings contribute to the expanding knowledge of genetic manipulation in H. axyridis and provide insights into its potential for future research and practical applications for biocontrol and invasive species management.