Genetically Predisposed?

Having read many posts recently, I am struck by the large number of folks on the forum who have mentioned that  they have relatives with MS.

My understanding is that MS is not inherited but there is a genetic predisposition to family members which makes it slightly more likely that someone else in your family may also have it.

What does this mean? If it is not genetic..is is to do with the environment, the climate, the country where you live???? I am not sure that I understand the difference between genetic and genetic predisposition.

I have just been mulling over this genetic thing....as it is seems more than coincidence that so many people have relatives with MS.

What is your personal experience and understanding?

Thoughtfully yours, Sarah :)

[shoshin]

I don't really understand this either, but my incomplete understanding is that they think you need both a genetic predisposition and some environmental factors to get MS. So if you have a genetic predisposition (a lot of the ones that have been identified seem to be genes that are associated with the immune system) and then encounter some environmental trigger (like a virus), you'll get MS. People without the genetic predisposition would encounter the same trigger and get no effect. Or, even if you have the genetic predisposition, if you never encounter an environmental trigger, you'll never get MS. So it's a two-step process. Your vulnerability could also maybe be affected by other environmental factors like vitamin D levels or various chemicals.

Genetics has turned out to be a lot less hard-coded and more complicated than researchers thought it would be when they were all excited about mapping the human genome. In fact, genes and the environment interact a lot and there are very few things that turn out to be like Huntington's where one gene always and inevitably leads to a certain disease. There is also a whole fascinating field called epigenetics that looks at how environmental factors can turn genes on and off and how these changes can even be inherited.

There was a fascinating study in Nature recently where scientists compared the genetic profile of identical twins, one with MS and one without: http://www.nature.com/news/2010/100428/full/4641259a.html The scientists didn't find any difference, but they only looked at one type of immune cell (and not brain cells). Both of the twins did have gene sequences that are known to predispose people to MS.

Quix has written on this topic before and said that there is an increase in risk for children of people with MS, but that it is quite small. "In the general population you have about a 1 in 750 chance of developing MS.  If your parent has MS then your chance rises to about 1 in 35 to 50." (http://www.medhelp.org/posts/Multiple-Sclerosis/What-about-having-children-with-MS/show/538073)

sho

PS I was glad to see your trial's back on.

[tonyad]

  Hey there  :)

   Sorry I do not have a whole lot of info on this also but just as curious as you are on the subject.  My Auny has MS and then of course me...so there is two of us in my family.

    It will be interesting when  medical research can come up with accurate answers on this as I hope this is not the case becausee I have have 4 daughters and 1 son and 2 Grandchildren I pray that they do not have to ever be diagnosed w/ this disease.

   Good Topic Sarah  :)
~Tonya

[RedFlame]

Hi Sarah,  it's always good to see you smiling face!

I have heard that if you have a family member with MS you are 10% more likely to develop MS.  On my mothers side I have 2 cousins with MS, and an aunt with ALS.  I'm not sure if this is statistically significant though as my mom had 10 brothers and sisters and there are over 40 cousins.  So I'm not sure if my case is meaningful.  

It was terrifying to watch my poor aunt.  She knew everything that was happening around her but couldn't move.  My cousins had to take care of everything for her.  It terrified me.  OK I'm off topic

I will be watching this with great interest

Red

[shoshin]

I don't really understand this either, but my incomplete understanding is that they think you need both a genetic predisposition and some environmental factors to get MS. So if you have a genetic predisposition (a lot of the ones that have been identified seem to be genes that are associated with the immune system) and then encounter some environmental trigger (like a virus), you'll get MS. People without the genetic predisposition would encounter the same trigger and get no effect. Or, even if you have the genetic predisposition, if you never encounter an environmental trigger, you'll never get MS. So it's a two-step process. Your vulnerability could also maybe be affected by other environmental factors like vitamin D levels or various chemicals.

Genetics has turned out to be a lot less hard-coded and more complicated than researchers thought it would be when they were all excited about mapping the human genome. In fact, genes and the environment interact a lot and there are very few things that turn out to be like Huntington's where one gene always and inevitably leads to a certain disease. There is also a whole fascinating field called epigenetics that looks at how environmental factors can turn genes on and off and how these changes can even be inherited.

There was a fascinating study in Nature recently where scientists compared the genetic profile of identical twins, one with MS and one without: http://www.nature.com/news/2010/100428/full/4641259a.html The scientists didn't find any difference, but they only looked at one type of immune cell (and not brain cells). Both of the twins did have gene sequences that are known to predispose people to MS.

Quix has written on this topic before and said that there is an increase in risk for children of people with MS, but that it is quite small. "In the general population you have about a 1 in 750 chance of developing MS.  If your parent has MS then your chance rises to about 1 in 35 to 50." (http://www.medhelp.org/posts/Multiple-Sclerosis/What-about-having-children-with-MS/show/538073)

sho

PS I was glad to see your trial's back on.

[Lulu54]

Sarah- i missed that you were back in the trial.  I'll go look for your post/journal on that .....

The genetic predisposition thing is a million dollar question.  You are right - we have had a bunch of people here lately who had close family members with MS, too.

Thanks Sho for offering a researcher's eye to this question.

-L

[starryeyes1]

My dad has MS and I just got dx last summer. I firmly believe that its a genetic thing. I now worry about my 19 yr old daughter. She has said funny things to me about a certain spot on her leg feeling like a sunburn, a vibrating kneecap, tingling in the legs.

I don't have all of these symptoms and have never talked about the "hotspot" that occurs with some MSers. This worries me. She has me and my dad on one side of her family and her gramma on her dad's side died from Scleroderma, an autoimmune disease.

I hope neither of my kids get MS and I don't want her to assume that she's too young for this. It does not discriminate.
Kristi

[twopack]

One word screamed out to me in Shoshin's post.  VULNERABILITY
I think that describes predisposition as well as the feelings members are describing.

Inherited diseases can usually be identified in the DNA or linked directly to one dominant or two recessive genes passed on from a person's parents.  Even if the offending DNA hasn't been identified yet, it's existence seems clear.

Other conditions or diseases are caused by spontaneous mutation.  They may be common with recognized triggers (Down's) or unusual with unknown cause (some forms of Ehlers-Danlos syndrome).

It seems that as long as the exact cause of MS (or some cluster of MS type diseases) remains in question, the best researchers can do is say they have observed an increased number of cases within families - so you are vulnerable or predisposed.  Now maybe it's just me, but it seems that jumping from 1 in 750 to 1 in 50 is more like a leap than a small increase in risk.

BTW, when my daughter visited the neuro with me and we were discussing vitamin D levels, he suggested she ask her doctor to draw a level and then offered his dosage suggestion for a daily supplement.  He mentioned talking to her daughters pediatrician as well, specifically to attempt to weight the MS predisposition scales in their favor.

Mary

[Sparkysarah]

Thanks for interesting responses....I wonder what research will have found out in ten years time?

Cheers for now

Sarah :)

[siv1]

From my case , it is environmental related.
I have not a single family member ever been diagnosed with MS and every one of them lived over 90yr with good health.(Except me of course)

Most of the places mention about people from Asia that lived their life up until 16yrs in those countries don't get MS.

I lived up until I was 18, but I moved to Scandinavia(highest population with MS) and then to USA. According to my neuro, I most likely got it because of environment.

In reality  I just wish I never got it.