The research contradicts the results of a recent study, which found affected fathers were more likely than affected mothers to transmit the risk of developing MS to their children.
Researchers studied 3,088 Canadian families with one parent affected with MS. Of the 8,401 children in those families, 798 had MS.
The study found equal transmission of the genetic risk of MS to children with 9.41 percent of fathers transmitting MS to their children compared to 9.76 percent of mothers.
We also found there were equal numbers of daughters and sons receiving the genetic risk of the disease from their parents, said study author George Ebers, MD, FMedSci, Action Research Professor of Clinical Neurology at the University of Oxford. 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 says the findings show no evidence of the Carter effect, which was recently cited in a study that found men with MS were twice as likely to pass the risk of disease on to their children. According to the Carter effect, men are more resistant to MS because they carry a higher genetic load and thus are more likely to transmit the genetic risk of the disease to their children.
Our study involved 16 times as many people as the previous published study. It casts further doubt on the widely believed multiple gene mode of inheritance of susceptibility to MS, said Ebers.
The study was supported by the Multiple Sclerosis Society of Canada Scientific Research Foundation.
The American Academy of Neurology, an association of more than 20,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as epilepsy, dystonia, migraine, Huntington's disease, and dementia.
For more information about the American Academy of Neurology, visit
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"Previously, access to prenatal testing was limited for some women when the affected male relative was not available for testing. The EmArray Dystrophin test greatly improves access to prenatal and carrier testing for women without the need to test a male relative, in a rapid timeframe," according to Vanessa Rangel Miller, MS. In addition to improved testing, the Emory Genetics Laboratory, Parent Project Muscular Dystrophy, leading researchers and clinicians are working together to develop a database for mutations and clinical data.
"Our new genetic test, along with new therapies currently in clinical trials, is a very positive development for muscular dystrophy patients and their families," says Dr. Hegde.
In the last five years DMD research has accelerated, resulting in more knowledge about the role of the dystrophin gene and an increased understanding about what happens to a muscle cell lacking the dystrophin protein. Researchers around the world are investigating a number of different treatment strategies, all with the goal of slowing or stopping muscle degeneration. Several clinical trials are underway and many others are in development, including testing of an oral medication intended to circumvent mutations in the dystrophin gene and increase normal gene expression.
According to Dr. Hegde, about 13 percent of mutations in the dystrophin gene are nonsense mutations--point mutations in a sequence of DNA that can result in mistakes in gene expression and nonfunctional proteins. New data published online in the current edition of the journal Nature show that PTC124, an investigational new drug designed to bypass dystrophin nonsense mutations and restore a functional protein, was effective in a preclinical (animal) model of Duchenne muscular dystrophy (DMD). (www.clinicaltrials).
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