How Do Fingerprints Form

Everyone has a fingerprint, it’s what makes us 100% unique. They are like snowflakes, no two people have the same, ever, but how do fingerprints form? It seems we do have similarities in fingerprints though, and formation is largely down to genetics. They are totally random, but in amidst the randomness, there is a glimpse of order, which comes, of course, form our genes and early development.

Volar Pads Control the Shape of a Print

A volar pad is something that develops on a foetus about 8 weeks into pregnancy. They are made from mesenchyme tissue which grows for a couple of weeks before stopping, while the hand continues to grow around it. It will eventually become the connective tissue like skin or vessels leading tot he skin. This happens on the feet too, hence toe prints.

When the volar pads smooth out into the skin, their movement and arrangement is controlled by our genes and so the patterns that form are different from one another.

Our Fingerprints

If the earliest ridges of a fingerprint grows slightly slanted, then a looping pattern is formed, this happens when the volar pad slants as the hand grows, and so it is unsymmetrical. If the volar pad is flat, then one of two things will happen depending on how prominent the volar pad is. If the pad has mostly disappeared into the hand itself then the fingerprint will form a arching pattern, but if it hasn’t then a more whorl like pattern is seen. Both of these show much more symmetry than a ridge pattern ever would, and all are similar between family members, as they are controlled by our genes.

Even though the main structure of our fingerprints is determined by our genes, what follows after this process is totally random, and ends in everyone having completely unique fingerprints, even identical twins. Scientists still aren’t sure how this works, and how no 2 people have the exact same print, but we know how it starts, and that’s a start.