How do mutations create new traits?

1 Answer
Dec 21, 2015

The first thing to understand is how DNA works.

DNA basically directs the creation of proteins, like an instruction manual for an organism.

For example, inside DNA is a sequence of nucleotides that specifically directs the concentration of melanin to be produced in the eye, resulting in an organism's eye color.

However, when a mutation occurs, the instructions encoded in the DNA are permanently altered.

When the DNA is changed, the organism reads and follows incorrect directions, which manifests itself in the creation of different and incorrect proteins.

For example, the incredibly rare disease hypertrichosis is caused by a genetic mutation and is characterized by the profuse growth of hair all over the body in unnatural amounts. This occurs because the DNA has been altered (mutated) in such a way that the instructions accidentally read to create much more hair than what's normal.