Re: what is HNPP

[Guest guest]

I'm very recently diagnosed with CMT but have not had a genetic test.

I've never heard of HNPP -- pardon my abject ignorance, but what the

heck is HNPP?? My feet are extremely numb. I first had tingling in my

feet when I was 18. Now that I'm 45, I have almost no feeling at all

in either foot (my right foot was affected earlier and to a greater

degree than my left foot) and cuts and blisters take months

(literally) to heal.

My lower right leg also has a lot of numbness in the past year. I've had

occasional numbness in my hands over the years, but it's been quite pronounced

in my right hand in the past month especially -- and that scares the hell out of

me for obvious reasons and because I've not been able to work very much (I'm a

self-employed web designer and this is killing my business). Please tell me more

about HNPP.

[Guest guest]

In 1992 the gene problem that causes CMT, was identified by Dr. Lupski.

CMT is associated with a duplication on chromosome 17p11.2-12. This chromosome

contains an important myelin gene, peripheral myelin protein-22 gene (PMP22).

CMT has an extra copy of PMP22.

A year later, in 1993, Dr. Phil Chance, et al, discovered that HNPP is caused by

a deletion (loss of a copy) of PMP 22 on the same chromosome where CMT has a

duplication. Two copies of a gene are usually needed for normal function.

More about it at http://www.hnpp.org/

[Guest guest]

Good website for HNPP is www.hnpp.org

I have HNPP, just diagnosed a month or so ago after a genetic test so I am also

struggling to understand it, you arent the only one!

Kathy