It seems that every so often we see people acting as if mutations just don't happen. They claim that since there are DNA repair mechanisms in humans and other species that mutations simply do not occur.
Just to show that they really do happen, I would like to reference the following paper:
http://www.nature.com/ng/journal/v46/n8/full/ng.3021.html
secondary article here:
Population Whole-genome Sequencing: Dutch Edition | MassGenomics
In this paper they looked at the genomes of two parents and one of their children. By doing so, they can find the DNA sequences in the children that did not come from the parents. These are the mutations.
How many families did they look at? 250. That's a lot. Here is an interesting chart showing that the number of mutations loosely correlates to the age of the father:
So yes, mutations do occur, even in humans.
Just to show that they really do happen, I would like to reference the following paper:
http://www.nature.com/ng/journal/v46/n8/full/ng.3021.html
secondary article here:
Population Whole-genome Sequencing: Dutch Edition | MassGenomics
In this paper they looked at the genomes of two parents and one of their children. By doing so, they can find the DNA sequences in the children that did not come from the parents. These are the mutations.
How many families did they look at? 250. That's a lot. Here is an interesting chart showing that the number of mutations loosely correlates to the age of the father:

So yes, mutations do occur, even in humans.