NEW YORK (Reuters Health) ¿ People who suffer from sporadic hemiplegic migraine (SHM) ¿ a rare, often severe subtype of migraine in which attacks are associated with a weakness affecting one side of the body ¿ may want to consider genetic testing, researchers suggest.

Their suggestion is based on a study in which they found "familial genes" for this type of migraine in people who did not have family members experiencing the problem.

"Normally one starts searching for genes only in families in which several family members have a disease," Dr. Michel D. Ferrari, from Leiden University Medical Center in the Netherlands, told Reuters Health. "This is the first study looking for genes in patients with a severe type of migraine but without similarly affected family members. The study shows that genes are important even in so called sporadic migraine patients."