How movies mislead you about DNA

Let’s talk about facts that movies mislead you showing DNA magics


DNA Sequence

You might have seen in movies that DNA rolls in a long helical line. Well helical structure is something fundamental. However, DNA sequence is not continuous. It is usually broken into chromosomes (we have 46, 23 from each parent). So simple we got 23 couples of DNA sequences.

Read DNA and unlock the door


DNA from the foot marks or whatever that is left on the scene

In my line of work, researchers struggle when there is contamination. Even a clean sputum sample would carry a whole set of micro-organisms which render them useless. It is also the case that we don’t usually release any DNA carrying items to the environment, unless we bleed, spit or “never mind mentioning”. So its not as easy as it sounds or any faster than an interrogation.

How does the “Is this my kid?” thing works

Well for crime scene related matters or paternity test DNA is not sequences at all. Because its very expensive and time consuming. Instead chemical engineering techniques are used. Something similar to putting a pH paper and seeing the acidity (Not going into details).