Re: New member: MTM but negative DNA-genetic test. Anyone???
- Hi Pat & Sarah
Welcome to the group, this is a topic we have raised recently, we
have 2 boys with suspected X-MTM but DNA testing has proved
inconclusive, we were also told that the test was only able to
detect between 80-85% of mutations, however it is my belief that the
test is even less accurate then that (judging from the amount of
other people on this site who are in the same position), we will
soon be having a biopsy performed on Regan (who is 3-½ years old)
and if the test proves positive for X-MTM (which it should) then it
will open other options to us, because we have 2 effected boys in
our family we can try and identify the mutation through a process
called linkage analysis where they take DNA from both boys and
compare them, this way they can find a mutation even if they do not
yet know about it, I don't know if you have anyone else in your
family with this myopathy but if you have a brother, cousin or
nephew with the condition then it may be possible to identify the
mutation this way, getting a genetic diagnosis will be useful not
only because you will be able to be tested in future pregnancies but
also other family members will be able to be tested to determine
there carrier status.
We would love to hear more about your son and if you want you can
even post some photos on the site, this site a great place to chat
to other people in the same position as yourself, so whatever you
need be it advice or just talking to somebody who understands what
your feeling this is a group of friends from all over the world and
we are all here for each other.
Take care Moz, Rachel & boys
--- In Myotubular_Myopathy@yahoogroups.com, "pinksarah21"
> Hi, gang. We are new to this group.
> Our 5-year-old son has myopathy, and the biopsy when he was 1-year-
> confirmed the myotubular/centronuclear appearance of his musclecells.
> But his DNA tested negative for the gene defect (XL-MTM testedDNA
> negative at the University of Chicago lab). We were told that the
> test is negative 15-20% of the time, presumably because themyopathy
> in such a case is being caused by a gene abnormality that has notyet
> been identified.similar
> Are there other members in this web group whose kids have a
> pattern (postive biopsy but negative DNA test for MTM)?
> Or others who have experience/knowledge about this?