Study: Family Risk for Developing MS

[Marco]

MS seems to be primarily caused by genetic factors, and secondarily by individual risk factors. A shared environment does not appear to be of any significance. The estimated risks in this study turned out lower than the previously reported high risks. The risk for a sibling to a person with multiple sclerosis for developing disease was seven times higher compared to the general population, while the risk for a child of an MS patient was five times higher. The study found no increase in risk for grandchildren and nieces/nephews.

These numbers are LOWER than previously thought.

http://www.sciencedaily.com/releases...0122091451.htm

[Jules A]

The article says:

"Even though multiple sclerosis is largely caused by genetic factors, the risk of patients' relatives developing the disease is lower than previously assumed."

Very interesting, thanks for sharing it.

I would like to know the previous risks they are referring to especially because it seems a lot of folks here deny there needs to be a concern of passing MS along.

An additional 5 or 7 time greater risk is significant, imo.

[fairpace]

I agree with Jules A. "Largely caused by genetic factors" says enough to give me pause.

I wonder what the percentages are for families in which two close relatives have MS [e.i., siblings (my scenario) or parent and child]? Perhaps I don't really want to know!

[Marco]

fairpace -
If one identical twin gets MS there is only a 25% chance that the other will get MS.

[Thinkimjob]

It's hard to tell. I am the only person in my extended family Dutch/ Irish/ English/ Scottish/ French/ Orstralian who has MS. But, back in ye olde days people had diseases and were bed-bound, and no one really knew what it was.

We're not big breeders these days. That was my first thought when diagnosed, "Ah ha, that's why Mum had so many miscarriages. Something wrong with the gene pool."

[onlyairfare]

Thanks for posting this. It's very interesting, and of course good news if the risk is less than previously thought. Yes, there is still higher risk for sibs and children of MSers than for the general population, but not as much as thought.

Most of us here don't deny there is risk of passing the disease on to our kids, but rather some might think that the benefit to our kids of being born and living life outweighs the ~3% risk of developing MS if your parent has MS. And then of course some of us had our kids either before we knew we had MS, or back when the genetic risk really was denied.

And I wonder if the result that shared environment did not seem to make a difference is related to the (presumed) fact that the study involved all Swedes diagnosed with MS since 1968, but (presumably) ONLY Swedes - they all shared the same Swedish environment.

I say "presumed/presumably" because I think Karolinska Institute tracks health outcomes of citizens born in Sweden who later move to other countries; and also, some non-Swedish-born people move into Sweden and are then diagnosed.

[Jules A]

I didn't read it as 3% increased risk of developing MS but more like 5-7 times higher.

"The risk for a sibling to a person with multiple sclerosis for developing disease was seven times higher compared to the general population, while the risk for a child of an MS patient was five times higher." from OP's link and

"The heritability was estimated to be 0.64 (0.36–0.76), whereas the shared environmental component was estimated to be 0.01 (0.00–0.18)." from original article:

http://brain.oxfordjournals.org/cont...in.awt356.full


I also have never understood the comparison of people who have had children purposely after a MS diagnosis with people who had their baby before they knew there was an increased risk. Maybe its just me but that is apples and oranges imo.

P.S. I don't think there really is such thing as a "Swedish environment". It is actually an entire country of like 9+ million people.

[onlyairfare]

The 3% risk of my kids developing MS because I have MS is a number I have been cited by many of my own physicians over the past few years, though clearly there is wide variation. In families where there are "clusters" the risk is perhaps higher than 3%, while I also recall being told 30 years ago that it was very unlikely - less than 1% risk - that my kids would develop MS just because I had it.

Just to make the math easy, maybe the incidence of MS in the general population is 1 per 1,000 (not a bad guestimate). If the risk is 5 - 7 fold higher, that would indicate 5 - 7 cases of MS per 1,000 population, which is indeed less than 30 per 1,000 (the 3% I've been told). Bottom line, we still really don't know.

As far as "Swedish environment," yes it is a whole country, but all of the country is in the northerly latitudes, almost all Swedes are Caucasian, the nation has socialized medicine so everyone has access to health care, and because it is an affluent nation with less income inequality, the standard of living is overall fairly high.

When discussing the incidence of MS, different environmental factors frequently cited include geographical location, race, income, and access to care. Compare this to the US where we have arctic environments in Alaska and tropical climates in Hawaii and everything in between; racial diversity; 15% of the population without health insurance and thus limited access to healthcare - including MRI's, neurologists, and DMT's.

I don't recall any studies comparing families who have children before and after the parents' MS diagnosis, so I have no idea if they are medically different. There would seem to be a philosophical difference, and certainly those who are really ill in an advanced stage of MS would be less likely to have children.

[Jules A]

I don't recall any studies comparing families who have children before and after the parents' MS diagnosis, so I have no idea if they are medically different. There would seem to be a philosophical difference, and certainly those who are really ill in an advanced stage of MS would be less likely to have children.

Thanks for replying. No, no studies just my curiosity because the group people who had children without knowing they had MS often seemed to get lumped into the same sentence in posts about those who are explaining their post-diagnosis decision to reproduce and I don't believe there is a connection other than the obvious increase risk of getting MS.

I also often wonder why threads like this and others discussing studies and the real nuts and bolts of MS seem to get passed over with minimal responses in favor of what I feel are more superficial topics.

Then again I don't ever read books for pleasure, only for knowledge, so its likely my view that is skewed, at least according to my Mother anyway.

[Tawanda]

Tip of the iceberg regarding genetics?

MS seems to be primarily caused by genetic factors, and secondarily by individual risk factors. A shared environment does not appear to be of any significance. The estimated risks in this study turned out lower than the previously reported high risks. The risk for a sibling to a person with multiple sclerosis for developing disease was seven times higher compared to the general population, while the risk for a child of an MS patient was five times higher. The study found no increase in risk for grandchildren and nieces/nephews.

These numbers are LOWER than previously thought.

http://www.sciencedaily.com/releases...0122091451.htm

These studies are very hard to do as it takes generations of data to be accurate. Especially when it comes to grandchildren, nieces and nephews. The gene might become diluted but not eradicated.

My mother was diagnosed with MS before I was born (late 50s?). I wasn't diagnosed until 32 years after she died at the age of forty. It took over half a century to connect the dots. Meanwhile during the 1980s and 1990s, 3 first cousins were diagnosed with MS.

In other words, it took an extremely long time to uncover just how much MS has invaded our family. You are not an "MS cluster family"...until you are! My Mom was dead and buried for decades and never had to find out about me and my cousins. That was the one break God gave her, I guess.

[onlyairfare]

True, especially here in the US.

However, in Sweden where the study was done, it is common to keep detailed records over many generations. The study cited included virtually all patients diagnosed with MS and treated for it since 1968.

Because it is a relatively small and homogeneous population, and because excellent centralized medical records are maintained, "clusters" are found much earlier, traced much easier. Doing genealogy research on my (Swedish) grandmother's side of the family, it was pretty easy to find detailed history back almost 200 years, allowing for the fact that medical science has progress a lot since then. That's 10 generations.

Now that medical science has defined the human genome, and as more genes associated with MS are identified, I think we will see much more accurate identification of the role genes play in MS.

[JerryD]

All of this information is great, but it would be better if medical science was able to use this info to develop a 'cure'. I understand the value of investigating the causes of the disease but it shouldn't divert focus from working feverously to find a 'cure'.

[Tawanda]

Now that medical science has defined the human genome, and as more genes associated with MS are identified, I think we will see much more accurate identification of the role genes play in MS.

150 genes last I heard.

I think it has already been mentioned that MS was probably under-reported in earlier generations because it was harder to diagnose. The MRI has hopefully eliminated that variable for current and future studies, but IMHO, as time goes on (and barring an out and out cure for MS), I predict higher numbers. I think these types of reports are in their infancy, but I am grateful that DNA can finally be dissected as it relates to MS. In fact, I am thrilled that the genetic component is being acknowledged at all...that was a long time coming for my family.

[pennstater]

Tawanda - definitely agree that this is just the beginning. There is so much to learn and I am sure the field will start exploding.

Jules - I sometimes struggle with the scientific articles and need to take time to read it multiple timed on good days to make sure I understand it. I am probably not alone in this, which could be why some of us don't comment.

As exciting as gene mapping is, it also scares me. The US laws really need to catch up to science to protect those of us with a less than stellar gene pool! I can visualize all the unethical ways this data will get used.

To the topic, no known MS in family. We suspect my Mom may have a "mild" firm of MS, but at 84, she does not want to know. But my Mom recalls a great aunt of hers intermittently in a wheelchair in the 1930s. But if you want to talk auto immune diseases, my gene pool hits the lottery.

[Tawanda]

All of this information is great, but it would be better if medical science was able to use this info to develop a 'cure'. I understand the value of investigating the causes of the disease but it shouldn't divert focus from working feverously to find a 'cure'.

YES, YES and YES! Too many ways to diagnose horrible illnesses and to few treatments and cures to go along with it. My hope is that one of these studies is going to lead the EUREKA! moment that leads to the cure or to a vaccine. It can't happen soon enough for me, Jerry D!