Published: Thursday, June 28, 2007 | 12:42 PM ET
TORONTO (CP) - A study of Canadian families with a parent who has multiple sclerosis has found men and women transmit the genetic risk of MS equally to their children.
The study, published Wednesday in the online edition of the journal Neurology, contradicts an earlier finding that fathers with MS were more likely than affected mothers to pass on the risk for the disease.
For this latest study, the researchers looked at 3,088 families with one affected parent and found that among the 8,401 children, there were 798 with multiple sclerosis.
In the end, they found equal transmission of the genetic risk to children, at 9.4 per cent for fathers, compared to 9.8 per cent for mothers.
Dr. George Ebers, a professor of clinical neurology at the University of Oxford, says his study involved 16 times as many people as the previous research, which had found dads were more likely than moms to transmit the risk of developing MS.
This new study also found no difference in the numbers of daughters and sons receiving the genetic risk of the disease from their parents.
"Intriguingly, we also found when half-siblings both have MS, there is a clear maternal effect, with mothers much more likely to be the common parent," Ebers said in a release.
The families studied had children born before 1980, so offspring would have at least reached the peak age for the onset of multiple sclerosis, which is estimated at 25 to 30 years old.
If families had both parents affected by the disease, they were removed from the analysis.
© The Canadian Press, 2007