DNA testing

[lovemyfurkids]

I met with Dr. Mankowitz on Thursday and while naming some tests that have not been done on me, he mentioned DNA testing. He was just asking if it was something I wanted done. I am not sure exactly what it is for, but my husband said since we are too old to have any more kids and our one son is adopted, he doesn't have to worry about getting HCM. So my husband says there is no reason to have DNA testing done. Is that what it is for? To see if it would be passed on to your children or is there other reasons to have it?

HCM is very very strong in my family (on my mother's side).

Just would like to know what it is about and not have my husband making decisions for me, with out either one of us knowing exactly what it is for and what it would show.

[Midge Rollins]

Re: DNA testing

Yes, they would be checking for the HCM gene. Since you are done with hving your family, and your son is adopted I would personally not have the test done. Others can chime in here though and give their opinion.

[cimdxb2]

Re: DNA testing

Does he have a sister or brother? Do they have kids? You can also go up and down the tree. For example if he tests positive and his parents are still alive they could be tested. If you can isolate the path, it can provide information to others.

If there aren't any concerns like above, I have to agree that testing really doesn't buy you much. The only other thing I have heard is that by identifying what kind of gene group you are in may help in treatment down the road.

[gfox42]

Re: DNA testing

If a person has an HCM gene, the chance that of a sibling also having it is equal to the chance that a child also has it. In other words, on average each of your siblings shares half your genes, and each child shares half your genes.

One important difference, though, is that most people have a lot less influence over their siblings' medical choices than they do over their kids'. If you have HCM and genetic testing successfully identifies a causal gene, then it's simple to look for the same thing in your kids. It's technically just as easy to look for it in your siblings, but they may or may not be willing.

As you go farther away in a family, the chance of sharing genes decreases -- each additional step away, it halves. I share 1/4 of my genes with each uncle, and 1/8 with each first cousin, etc.

One thing to be aware of: this chance of sharing a gene is independent for each relative. In other words, if you have an identified HCM gene, each child independently has a 1/2 chance of having it as well, and so does each sibling.

Gordon

[lovemyfurkids]

Re: DNA testing

I only have one sibling and he already has it and is being treated for it. He has a defib/pacemaker implanted. My grandmother had HCM, my mom did and all of her siblings did. (only one brother of her's is still alive, everyone else died of it, except one brother of her's who died of cancer) All my cousin's have it.

So far none of my niece's have it, but for some strange reason in our family, it isn't found until the age of 40 or over. Everyone in my family that has it and has been diagnosed, was done so over the age of 40. No matter how many echo's or heart caths, none of those find HCM until someone reaches 40 years old. None of my nieces are that age yet.

I know it sounds strange, but that is the way the HCM seems to run in our family. It isn't the doctor's or testing we are all using, as we all see different doctor's in different cities and I am in even a different state (they all are spread out in Illinois).

Sounds like since all the other family already know if they have it, and we are not going to be having any biological children ourselves; the genetic/DNA really wouldn't serve that much of a purpose for me.

Thanks to everyone who helped out with explanations and advice and such.