Feb. 16, 2010 -- A newly discovered genetic link may offer new information
on the causes of attention deficit hyperactivity disorder (ADHD) as well as
help determine who might best respond to treatment.
Researchers have found that a genetic variant on the latrophilin 3 gene
(LPHN3) is associated with ADHD in several different populations. Previous
studies have also shown that this gene plays a role in how people respond to
the stimulant medications often used to treat the childhood behavioral
"It is very intriguing that the same variant (SNP marker rs6551665)
associated with susceptibility to ADHD is also associated with response to
stimulant medication," write researcher M. Arcos-Burgos of the National Human
Genome Research Institute at the National Institutes of Health in Bethesda,
Md., and colleagues in Molecular Psychiatry. "This opens a window for
the evaluation of molecular substrates of ADHD and development of new drugs
targeting new genes and brain pathways involved in ADHD."
Although several other genes have been linked to ADHD in previous studies,
few of these linkages have been confirmed by replication in other
In the study, researchers showed an association between LPHN3 in an isolated
population in Colombia and then were able to replicate those results in five
different populations from other areas of the world, including Germany, Norway,
Spain, and the U.S.
Further brain testing results were also able to confirm this connection by
showing that LPHN3 is expressed in brain regions involved in attention and
activity as well as how the brain responds to ADHD stimulant medication
Researchers say the results could help identify people who are susceptible
to ADHD and those who would be more likely to respond to stimulant medications
as a part of their ADHD treatment.