DNA Extraction

For you who always wonder how did Deoxyribonucleic Acid (DNA) – this incredible tiny things on human body – could be sequenced so scientists have the data about all genetic diseases to discover the treatments. Well, the first thing we should do is take blood sample from the patient and extract it. DNA extraction is a process to separate DNA from each components of cellular material in the cell. Phosphate groups that attached to the bases of DNA make DNA charged negative. Moreover, when the DNA unwound from sugar-phosphate backbone, it is stabilized by magnesium in the cell. If you sequence all DNA in humans, you’ll find there are 3.2 billion base pairs. The DNA then coiled around histones (positively charged protein) to form nucleosomes. The function of magnesium also seen in protease, enzyme that cut DNA. to break this twisted DNA around histones, the procedures to extract DNA have common elements[1].

Therefore, DNA extraction follow steps below[1]:

1. Lyse (break open) the cells

2. Separate the DNA from the other cell components.

3. Isolate the DNA.

The disrupted cell membranes is occur because of[1]:

1. Heat to enhance fluidity

2. Dithiothreitol (DTT) to unwind disulfide bonds

3. Detergent or sodium dodecyl sulfate (SDS) to destabilizing the membrane

To fulfill your curiosity, you can try try-at-home experiment to extract DNA from any fruit. Indeed, the procedures might be different from what I’ve told before, however the picture below[2] has successfully done by scientists.

REFERENCE

[1] Elkins, K.M., 2013, Forensic DNA Biology, Academic Press.

[2] National Human Genome Research Institute.