The gene variation may make it hard for the body to sense blood-sugar changes so the brain doesn't get the signal to stop eating.
No direct correlation between gene variation and autism was found.
However, scientists don't yet know all of the gene variations that contribute to schizophrenia.
As a result of the multiple gene variation, more than 50% of white people are heterozygous.
There is also some concern that PE would have a strong position in the two types of technology used in studying gene variations.
That's because people with a certain gene variation may be up to seven times more likely to get AMD, a new study shows.
Most genetic tests marketed directly to consumers are for common gene variations linked to an increased risk of certain illnesses.
People with a gene variation associated with Alzheimer's can do little more than worry.
"We might be able to predict, based on the presence of this gene variation, whether someone will respond to certain antidepressants."
With very little gene variation within the species, healthy reproduction becomes increasingly difficult, and offspring are more likely to deal with problems such as inbreeding.