Selectable Marker
A selectable marker protects the organism from a selective agent that would normally kill it or prevent its growth. In most applications, only one in a several billion cells will take up DNA. Rather than checking every single cell, scientists use a selective agent to kill all cells that do not contain the foreign DNA, leaving only the desired ones.
Antibiotics are the most common selective agents. In bacteria, antibiotics are used almost exclusively. In plants, antibiotics that kill the chloroplast are often used as well, although tolerance to salts and growth-inhibiting hormones is becoming more popular. In mammals, resistance to antibiotics that would kill the mitochondria is used as a selectable marker.
Read more about this topic: Marker Gene
Famous quotes containing the word marker:
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