Sep 02, 2001 (United Press International via COMTEX) -- The people of Finland have given the world Nokia cell phones, the sauna and most recently a valuable clue in the search for the cause of migraine headaches.

Aarno Palotie and his colleagues at the University of California, Los Angeles recently conducted a study of migraine-prone families in Finland. The goal was to narrow down the location of genes associated with migraines, however, their research led to the discovery of a "susceptibility locus," a region of a human chromosome linked to how prone people are to getting migraines.

According to the American Medical Association, more than 26 million people in the United States suffer from migraine headaches. There is no medical test for migraine, so diagnosis usually is based on the appearance of one or more of a series of symptoms: throbbing pain, possibly on just one side of the head, nausea and sensitivity to light and sound.

Despite the large number of people who suffer from migraines, a cause has eluded researchers. Since there is evidence of the illness running through families, researchers have long suspected there might be a genetic component to the disease.

The study by UCLA researchers may help narrow the focus of the investigation to a region of a single chromosome. Palotie and colleagues are geneticists by training. Their "special strategy" as Palotie deems it, is to conduct their search among families in Finland that have a high incidence of migraine sufferers.

"The Finnish population is unique," Palotie said. "They have a high standard of living, a high health care standard, and a very good level of record keeping. Combined with the fact that Finland's present inhabitants are descended from only a handful of people that arrived 2,000 to 4,000 years ago, this makes them a very good group to help find the genes associated with migraine."

Palotie said the relative isolation of the Finnish population and their ancestory reduces the "noise" in their DNA, which allowed researchers to more efficiently search for anomalies among the genetic codes of various families and lead to the discovery of the new locus.

Other groups searching for genetic components of migraine have only been able to find causal genes for only the more rare forms of the headache, such as familial hemiplegic migraine in which headache pain is accompanied by partial paralysis.

This study is a first step in understanding the genetic basis of the more common types of migraines.

Kenneth Mack, a researcher at the Mayo Clinic, described migraine as a "heterogenous disorder."

"The thing about these illnesses is that genotype doesn't always lead to the same phenotype. It wouldn't be surprising at all if the same genetic code leads to a whole host of migraines with different symptoms. That's what makes this such a difficult problem," Mack stated.

Palotie's team plans to continue narrowing down their search for the actual genes responsible for migraine by screening the genetic code of more families from Finland and then extending the study to a group of families in Southern California.

When asked about the potential to develop therapies based on genetic analyses such as those done by the Palotie, Mack replied: "That is a very exciting question and for some forms of migraine we already have seen that drugs that work on certain proteins called calcium channels relieve the suffering in some patients. So the potential is definitely there. It's a very exciting problem and I wish the researchers at UCLA luck with their study."

UCLA researchers expected their findings will be published within the next few weeks.

　　From Healthy.net