The Human Genome is made up of 3 billion base pairs (”G”s, “C”s, “A”s, and “T”’s). A SNP is a single difference or variation at a base pair in a DNA sequence.

Sometimes, when the genome is copied to make a new cell, a single base pair can be left out, added or changed. These single base pair substitutions make SNPs. There are approximately 10 million SNPs in the human genome which accounts for many genetic differences between you and everyone one else on this planet.

Since variations are passed on from one generation to the next, the number of differences between your DNA and your friends can tell you how closely you are related to each other. When we compare the genome of any 2 people they are nearly the same. But DNA between any 2 people differs on average of 1 out of every 1000 basis.

Most SNPs are so insignificant that they have no affect at all to the way a specific gene functions. Some SNPs however can cause a gene to function at minimal, altered or diminished capability. For example a SNP can result in ones skin aging faster and another SNP can cause ones skin to be more susceptible to damage from Environmental factors such as pollution or sun damage.

These types of evolutionary changes can ultimately lead to the survival of a species or population; Darwin’s Theory.

The Industrial Revolution and the White Moth.
This historical time set forth a technological pace which has helped create our modern economical era. Due to the Revolution, there was a drastic increase in pollution that left light-coloured trees blackened by soot. The white moth, a species that survived by effectively camouflaging against the light-coloured trees became easily spotted and began to drastically die off from predation. Over time, the white moths evolved and developed a greyer appearance that allowed them to camouflage within their environment again. This genetic variation ultimately led to the species survival.