My nephew also has a inframe deletion, his deletion is 8-21 but his phenotype is Duchenne, what I cant understand is why their body doesnt produce dystrophin, is there something stoping it as thier deletion points to them having Becker, and boys with Becker produce dystrophin.
PTC124 is for boys that have stop coden, meaning that something prevents the dystrophin reaching their muscles, couldnt that be the case with our boys. I am trying to get my head around it all and understand it

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Elaine,
Your nephew's deletion is sizable 8-21. Think of the dystrophin gene as a long assembly line if you will - that each step of the making of dystrophin is incredibly complex. When one of the steps is interrupted, it effects the whole chain reaction. So, when that happens, then no dystrophin is produced. With BMD - or Becker's MD, the location of the error is such that it does allow some dystrophin to be produced. There is actually a third type which is referred to as an intermediate where a smaller percentage of dystrophin is produced...but less the BMD.

The gene itself is 79 exons long and looks like a giant rubber band. Within it, there are what looks like rugs of a ladder. Each step has an amino acid, a,t,g,c. When a genetic error/mutation is formed, it is either a deletion, duplication, stop condon (like a period in a sentence only it is inserted at the wrong place in the sentence), intron, and this error interrupts the directions for dystrophin. The location of the error is signified by stating i.e. deletion of 8 -21, etc.

I would go into this site as well as MDA and read more. You are not alone - it takes time to understand DMD or BMD.
Hope that helps,
Char Burke
Hi - My son is missing 8 to 19. I am a little confused too.... I remember talking to the researchers at the PPMD conference 4 years and I am sure more is known now. I am still not sure if Alex has severe Becker or mild DMD. At 9-1/2, he still gets around very well. I am also confused on the inframe and out of frame too. I am not sure which one Alex falls under. I have the DNA report that was done and it says: at least exons 8 to 19 are missing. Promotor b through exon 6 is present and exon 32 through 60 is present. It talks about the general reading frame rule...blah blah.

Char - Can you point me to that Dr. Flanigan article. That sounds interesting. I am trying to get up to date on the latest research, clinical trials etc. I am a little out of touch.

Thanks. Kim
Hi guys, my nephew has an in-frame deletion of exons 4-18. He has been diagnosed with DMD due to his symptoms and his CK levels being around 12,000. I believe that in beckers the CK level is around 1,200 - 2,500. They are much much less than in patients with DMD, I have seen on some of the blogs patients with DMD having over 20,000 on their CK levels. Were you children's/nephew's CK levels checked? And if so what did they come back as?
Kim,

A deletion of exons 8 - 19 is predicted to be in-frame. This page is the easiest to check it on. I think the only way you'll get a definitive answer on whether it's BMD or DMD is a muscle biopsy. A complete lack of dystrophin is DMD is what I understand to be the technical distinction between Becker and Duchenne.

Nadine,

I want to say I've talked to parents that have seen 15,000+ CK levels in their child with BMD. I don't know that you can determine BMD vs. DMD with just CK.

My son's two tests have been 18,000 and 19,000.

Keith
My nephew's Ck is high up ( 20000). He has had a muscle biopsy and he does have duchenne. I still cant understand why its Duchenne when his deletion is inframe. Doctors have told us just by his deletion he should be a Becker but unfortunately he isnt. What I am trying to understand is why if the boys have a inframe deletion why do they have Duchenne and not Becker.
Hi Kim

The genetist we are with said that based on CK levels being so high, it is definetly duchenne so I am really confused now. She said there is no way it can be beckers with such high levels. So I don't know what to do now. Maybe I should get my sister to talk to his main doctors he sees once every six months. I will definetly look into it.
Nadine,

When my nephew was getting diagnosed, we just knew his deletion, no muscle biopsy was done when we found out. They first thought Becker but when they tested his CK levels over a period of time, they told us there is no way he has Becker due to the high level of CK. The only way we were to know was a muscle biopsy and it confirmed he did have Duchenne

Nadine Foley said:
Hi Kim

The genetist we are with said that based on CK levels being so high, it is definetly duchenne so I am really confused now. She said there is no way it can be beckers with such high levels. So I don't know what to do now. Maybe I should get my sister to talk to his main doctors he sees once every six months. I will definetly look into it.
It's interesting that now 2 people have mentioned being told that a high CK number means Duchenne instead of Becker. I had not heard that before.

Here's one website that says CK can range from 5,000 to 20,000 with Becker, but maybe the high numbers mean the "severe Becker" / in-frame Duchenne phenotype end of the spectrum?

If a high CK number is all it takes to diagnose DMD instead of BMD, then I'm even more disappointed that my original doctors didn't treat our case as DMD from the outset.
Interesting, as after going to Nationwide Children's last week, they completely ignore the CK level after a diagnosis is made to be in the category of DMD/BMD, as she said even a normal person has been proven to have CK levels as high as 15,000 after extrenuous exercise (even if their "resting" CK was normal, below the 200). They did a research study there (in Columbus at Nationwide Children's) and after that, have ignored the levels and won't really even discuss it as far as where a child fits or what a drop or increase in CK level mean. Kelvin's CK level dropped 16,000, from 34,000 in just 8 months, a huge drop, it could be great and they still can't determine where he fits for sure, DMD/BMD, even though he is out of frame, as his phenotype is looking good for BMD right now, but without a biopsy, we won't know, until he would progress, but since he has done nothing but improve over the last 3 1/2 years, they aren't sure if he is just in the "Cinderella period" or in fact is doing good. He only has very mild hyperthrophy and a bit of fine motor skill delay, otherwise, no troubles and he'll be 7 in September. I'm sure other kids are great until then too, that is why it is hard to know, but, well, we'll know someday. Michelle

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