The technique of DNA fingerprinting changed the era of identification, characterization, and classification of organisms.

Notably, approximately 99% of our DNA (deoxyribose nucleic acid) is similar. A 0.1% difference is sufficient to make someone so unique. We are using this 0.1% portion for DNA profiling which is often known as DNA fingerprinting.

There is a reason, why only DNA is used,

In all bodily parts, tissues, and cells (except germ cells) our DNA is the same. Even, after the death of the individual, it remains the same. It can remain stable even after 1000 years.

As we know, 97% of our genome is non-coding, repetitive, and junk, protein formation is regulated by only 3% portion, we know it as genes. Moreover, repetitive nature and polymorphic properties of junk DNA are utilized to perform DNA fingerprinting. The number of repeats and the sequence structure of those regions varies between individuals and organisms based on that the entire DNA profile or the DNA print can be prepared.