selectiemarkers
Selectiemarkers, often called selectable markers in English, are genetic elements that allow researchers to identify cells that have taken up a genetic construct. They are essential in genetic engineering, molecular cloning, and functional genomics because the introduced DNA usually exists in only a small fraction of cells; markers enable selection or screening of those that acquired the DNA.
Types: Selectable markers confer a growth advantage under selective conditions, such as antibiotics or herbicides, so
Common examples: Antibiotic resistance markers such as neomycin resistance (neo), kanamycin resistance (kanR), hygromycin B phosphotransferase
Applications: Marker genes are carried on transformation vectors alongside the gene of interest. Transformed cells are
Marker removal and regulatory considerations: For many applications, especially transgenic crops and therapeutic contexts, it is
Limitations: Marker expression can be silenced; marker burden may affect phenotype; cross-resistance and environmental spread are