When people set out to boost their IQ, they may employ a variety of methods. Some return to school, while others simply read more or start eating what they hear are "brain foods." No matter how hard they try, the ability to enhance cognitive function may hinge on whether or not individuals have certain genes.

These are the findings of a recent Alzheimer's study involving a team of more than 200 scientists from over 100 institutions. During the study, researchers analyzed brain and DNA data from 21,151 healthy individuals. As the scope of the project and sheer volume of information scientists had to work with was so large, they were able to discover new genetic variants among participants with larger brains.

The gene known as HMGA2 was found to affect the size of an individual's brain, as well as his or her intelligence. Furthermore, those with a slight variation to this gene were found to have higher IQs.

People may or may not have the right genes for a bigger brain, but they can get a good sense of how well they perform on a cognitive level by taking an IQ test.