Guest guest Posted March 3, 2000 Report Share Posted March 3, 2000 Gloria, This happens because of poor terminology. Unfortunately mitochondrial disease means 2 different things because mitochondria have their own DNA. The one that it is applied to among people who *know* what it is - is a disease process due to dysfunction of the mitochondria. The second definition is a disease caused by a defect in the mitochondrial DNA. The nuclear DNA also impacts mitochondrial function. And in fact, it is responsible for most of the diseases resulting from mitochondrial disease. There is a great article on the MDA site that talks about this a little bit and a page on the IMDN site (http://www.imdn.org/mitowhat.htm). There is actually a disease referred to as Leigh's and a disease referred to as MILS - MILS stands for Maternally Inherited Leigh's Syndrome. There is a form of Leigh's that is inherited through the mitochondrial DNA, but more often it is inherited as an autosomal recessive disorder - meaning both parents have a defective copy of a nuclear gene. Also, many diseases that are caused by a defect in the mitochondrial DNA are NOT inherited at all - but rather sporadic. This means that something happened in utero to cause a deletion of part of the mitochondrial DNA. Some of those disorders are CPEO, Kearns-Sayre, Pearsons, etc... I just wish doctors, teachers, therapists, etc... who don't know what the hell they are talking about would shut up! Sorry about that, it just really irritates me when parents are given such horribly inaccurate information. I was actually told that my son couldn't have a mitochondrial disorder because he didn't drool! I hope this helps - I know it's confusing, especially when there is so much inaccruate information. Terri >From: dsrtdwlr@... >Reply-To: Mitoonelist >To: Mitoonelist >Subject: Re: Terri??? >Date: Fri, 03 Mar 2000 16:39:18 -0800 > >Hi Terri, > About your info on Mito? I am soooooo confused??/Someone last night >said ALL mito disorders ARE maternally based???We have seen 2 cases of >supposed MS on my husbands side. And wonder if it is MS or Mito??KRC >seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! > >Gloria >Mom of an Angel > > >The fact is that MOST mitochondrial disorders are not maternally > > inherited but rather sporadic or autosomal recessive - in which case >there > > would be little or no family history. > > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 3, 2000 Report Share Posted March 3, 2000 In a message dated 03/03/2000 5:21:53 PM Pacific Standard Time, dsrtdwlr@... writes: > /Someone last night > said ALL mito disorders ARE maternally based???We have seen 2 cases of > supposed MS on my husbands side. And wonder if it is MS or Mito??KRC > seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! No . . . not all are maternally inherited. They can be inherited in ALL the following ways: maternal, autosomal recessive, autosomal dominant, x-linked, or spontaneous. I think I have been the " link queen " today!!! This article has a section on the genetics . . . it might help explain it better! <A HREF= " http://www.mdausa.org/publications/Quest/q64mito.html " >MDA / Quest 6-4 / Mitochondrial Myopathy -- An Energy Crisis in the Cells</A> <A HREF= " http://www.mdausa.org/publications/Quest/q65mito.html " >MDA / Quest 6-5 / Mitochondrial Disease in Perspective - Symptoms, Diagnosis an</A> Good luck! Kathy C. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 4, 2000 Report Share Posted March 4, 2000 Hi Terri, About your info on Mito? I am soooooo confused??/Someone last night said ALL mito disorders ARE maternally based???We have seen 2 cases of supposed MS on my husbands side. And wonder if it is MS or Mito??KRC seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! Gloria Mom of an Angel The fact is that MOST mitochondrial disorders are not maternally > inherited but rather sporadic or autosomal recessive - in which case there > would be little or no family history. > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 4, 2000 Report Share Posted March 4, 2000 Hi, Great explanation, a further explanation is warranted in one part, " ....Also, many diseases that are caused by a defect in the mitochondrial DNA are NOT inherited at all - but rather sporadic. This means that something happened in utero to cause a deletion of part of the mitochondrial DNA. Some of those disorders are CPEO, Kearns-Sayre, Pearsons, etc... " It doesn't necessarily happen in utero, mito dysfunction could be due to sporatic mutations ocurring any time thruout life, and it doesn't need to be a deletion, it could be a point mutation that exceeds a threshold ratio (the phenomenon of heteroplasmy)-above which the mutant elicits an effect, leading to dysfunction, often after stress to the system. Remember that mtDNA replicates relatively continually thruout life (estimated 1/2 life in the brain is 30 days, meaning that 1/2 is replaced every 30 days), so it is easy to imagine how a mutation could reach a threshold level, or not depending on stochastic processes ( " chance " ). One reason that it is sometimes said that the mutation is favored over the wild-type is that replication may be increased to try to compensate for the defect, but the defect may become even more prevalent, the dastardly cycle and morbidity is not thus hard to imagine. Best Regards, Steve 2nd NIH Mitochondria Minisymposium " Mitochondria:Interaction of Two Genomes " 14, 15 March 2000 <http://www.nih.gov/sigs/mito/March2000.html> J. Zullo, PhD Bldg. 10 Room 2D56 NIH Bethesda, MD 20892 FAX: zullo@... New Mitochondria Interest Group Web Page: <http://www.nih.gov/sigs/mito/> First generation Mitochondria Interest Group Web Page: <http://www-lecb.ncifcrf.gov/~zullo/migDB/> Phage-Tech Interest Group (PhTIG) Web Page: <http://www.nih.gov/sigs/phtig/> Re: Terri??? >Date: Fri, 03 Mar 2000 16:39:18 -0800 > >Hi Terri, > About your info on Mito? I am soooooo confused??/Someone last night >said ALL mito disorders ARE maternally based???We have seen 2 cases of >supposed MS on my husbands side. And wonder if it is MS or Mito??KRC >seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! > >Gloria >Mom of an Angel > > >The fact is that MOST mitochondrial disorders are not maternally > > inherited but rather sporadic or autosomal recessive - in which case >there > > would be little or no family history. > > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------------------------------------------------ MAXIMIZE YOUR CARD, MINIMIZE YOUR RATE! Get a NextCard Visa, in 30 seconds! Get rates as low as 0.0% Intro or 9.9% Fixed APR and no hidden fees. Apply NOW! http://click./1/2122/1/_/368657/_/952133288/ ------------------------------------------------------------------------ Brought to you by www.imdn.org - an on-line support group for those affected by mitochondrial disease. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 4, 2000 Report Share Posted March 4, 2000 Good point Steve - and thank you for clarifying that (although I won't even pretend to understand it! Isn't this where they think Alzheimer's might have a mitochondrial component - that as we age something goes wrong in the replication process? Terri > >Reply-To: Mitoonelist >To: " 'Mitoonelist' " <Mitoonelist> >Subject: RE: Terri??? >Date: Fri, 3 Mar 2000 23:16:29 -0500 > >Hi, >Great explanation, a further explanation is warranted in one part, > " ....Also, many diseases that are caused by a defect in the mitochondrial >DNA are NOT inherited at all - but rather sporadic. This means that >something happened in utero to cause a deletion of part of the >mitochondrial DNA. Some of those disorders are CPEO, Kearns-Sayre, >Pearsons, etc... " > >It doesn't necessarily happen in utero, mito dysfunction could be due to >sporatic mutations ocurring any time thruout life, and it doesn't need to >be a deletion, it could be a point mutation that exceeds a threshold ratio >(the phenomenon of heteroplasmy)-above which the mutant elicits an effect, >leading to dysfunction, often after stress to the system. Remember that >mtDNA replicates relatively continually thruout life (estimated 1/2 life in >the brain is 30 days, meaning that 1/2 is replaced every 30 days), so it is >easy to imagine how a mutation could reach a threshold level, or not >depending on stochastic processes ( " chance " ). One reason that it is >sometimes said that the mutation is favored over the wild-type is that >replication may be increased to try to compensate for the defect, but the >defect may become even more prevalent, the dastardly cycle and morbidity is >not thus hard to imagine. >Best Regards, >Steve > >2nd NIH Mitochondria Minisymposium " Mitochondria:Interaction of Two >Genomes " >14, 15 March 2000 <http://www.nih.gov/sigs/mito/March2000.html> > J. Zullo, PhD >Bldg. 10 Room 2D56 >NIH >Bethesda, MD 20892 > FAX: >zullo@... >New Mitochondria Interest Group Web Page: ><http://www.nih.gov/sigs/mito/> >First generation Mitochondria Interest Group Web Page: ><http://www-lecb.ncifcrf.gov/~zullo/migDB/> >Phage-Tech Interest Group (PhTIG) Web Page: ><http://www.nih.gov/sigs/phtig/> > > > Re: Terri??? > >Date: Fri, 03 Mar 2000 16:39:18 -0800 > > > >Hi Terri, > > About your info on Mito? I am soooooo confused??/Someone last night > >said ALL mito disorders ARE maternally based???We have seen 2 cases of > >supposed MS on my husbands side. And wonder if it is MS or Mito??KRC > >seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! > > > >Gloria > >Mom of an Angel > > > > > >The fact is that MOST mitochondrial disorders are not maternally > > > inherited but rather sporadic or autosomal recessive - in which case > >there > > > would be little or no family history. > > > > >______________________________________________________ >Get Your Private, Free Email at http://www.hotmail.com > > >------------------------------------------------------------------------ >MAXIMIZE YOUR CARD, MINIMIZE YOUR RATE! >Get a NextCard Visa, in 30 seconds! Get rates as low as >0.0% Intro or 9.9% Fixed APR and no hidden fees. >Apply NOW! >http://click./1/2122/1/_/368657/_/952133288/ >------------------------------------------------------------------------ > >Brought to you by www.imdn.org - an on-line support group for those >affected by mitochondrial disease. ><< attach5 >> ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 5, 2000 Report Share Posted March 5, 2000 It is one way that has engendered a number of studies. Steve 2nd NIH Mitochondria Minisymposium " Mitochondria:Interaction of Two Genomes " 14, 15 March 2000 <http://www.nih.gov/sigs/mito/March2000.html> J. Zullo, PhD Bldg. 10 Room 2D56 NIH Bethesda, MD 20892 FAX: zullo@... New Mitochondria Interest Group Web Page: <http://www.nih.gov/sigs/mito/> First generation Mitochondria Interest Group Web Page: <http://www-lecb.ncifcrf.gov/~zullo/migDB/> Phage-Tech Interest Group (PhTIG) Web Page: <http://www.nih.gov/sigs/phtig/> Re: Terri??? > >Date: Fri, 03 Mar 2000 16:39:18 -0800 > > > >Hi Terri, > > About your info on Mito? I am soooooo confused??/Someone last night > >said ALL mito disorders ARE maternally based???We have seen 2 cases of > >supposed MS on my husbands side. And wonder if it is MS or Mito??KRC > >seemed to fit alot of the outline of Leighs. SOOOOConfused???HELP!!! > > > >Gloria > >Mom of an Angel > > > > > >The fact is that MOST mitochondrial disorders are not maternally > > > inherited but rather sporadic or autosomal recessive - in which case > >there > > > would be little or no family history. > > > > >______________________________________________________ >Get Your Private, Free Email at http://www.hotmail.com > > >------------------------------------------------------------------------ >MAXIMIZE YOUR CARD, MINIMIZE YOUR RATE! >Get a NextCard Visa, in 30 seconds! Get rates as low as >0.0% Intro or 9.9% Fixed APR and no hidden fees. >Apply NOW! >http://click./1/2122/1/_/368657/_/952133288/ >------------------------------------------------------------------------ > >Brought to you by www.imdn.org - an on-line support group for those >affected by mitochondrial disease. ><< attach5 >> ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------------------------------------------------ PERFORM CPR ON YOUR APR! Get a NextCard Visa, in 30 seconds! Get rates as low as 0.0% Intro or 9.9% Fixed APR and no hidden fees. Apply NOW! http://click./1/2121/1/_/368657/_/952214076/ ------------------------------------------------------------------------ Brought to you by www.imdn.org - an on-line support group for those affected by mitochondrial disease. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 5, 2000 Report Share Posted March 5, 2000 gloria, just to chimne in here with my $0.02.....it is my understanding that NOT all mito disorders are maternally inherited. Heard Dr Boles speak about 2 yrs ago and he said it then and then our neurologist has told us the same thing. Also, many mito problems aren't ever able to be specifically diagnosed because there is no way of knowing FOR SURE exactly where the mtio deletions/mutations are (research isn't that far along). Hope i didn't just add to your confusion! ruth Quote Link to comment Share on other sites More sharing options...
Guest guest Posted March 6, 2000 Report Share Posted March 6, 2000 Part of the confusion here is also the fact that some doctors refer to mitochondrial disease, as only that disease that is caused by mitochondrial DNA mutation. It is the very strictest definition of the term " mitochondrial disease " and in this case, would be primarily maternally inherited. Although other doctors recognize " mitochondrial disease " as being any disease of mitochondrial dysfunction regardless of whether it is mtDNA or nDNA. I think it's a matter of semantics. Jeannine Quote Link to comment Share on other sites More sharing options...
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