I recently read this article from HDbuzz

Cell replacement therapy

In fact, this ‘cell replacement’ idea has a long history in HD. In the mid-1980’s, a series of animals studies showed that it was possible to fix brain damage caused by toxins, by transplanting embryonic brain cells into the damaged area. Subsequent work, in more sophisticated animal models, supported the idea that this approach might be beneficial.

Based on this animal work, and the progression of similar trials in Parkinson’s disease, a small number of HD patients received grafts of embryonic brain tissue starting more than 15 years ago. Disappointingly, none of the patients receiving transplants showed much, if any, sustained improvement in their HD symptoms after receiving these transplants.

One patient who received a fetal tissue transplant died about 18 months after surgery, due to unrelated causes (heart disease). While sad for the patient and their family, this enabled scientists to study the transplanted tissue and see how it was doing in the brain. One possible explanation for why the patients didn’t get much better is that the transplants may not have survived, or might not have made the right kind of connections in the host brain.

In fact, this early study showed that the fetal tissue did survive in the brain of the HD patient, and the cells in the graft seemed to make the kinds of connections they should have made with other cells in the brain. This is good news, because it means this kind of transplant is technically possible, but bad news, because it means we don’t know why it didn’t make the patient better."

However, there are severe ethical problems involved with this. I really would like to express a step by step thinking process on this concerning what the Bible says so I am better understood, but I'll try to get right to the point. From the instant of the fertilization of the egg, God has clearly said that the life begins. Psa. 139 contains these verses; 15, My frame was not hidden from thee, When I was made in secret, And curiously wrought in the lowest parts of the earth. (womb)
16, Thine eyes did see mine unformed substance; And in thy book they were all written, Even the days that were ordained for me , When as yet there was none of them.
17, How precious also are thy thoughts unto me, O God! How great is the sum of them!

Taking a baby embryo, and cutting into its brain just for the sake of my getting better is the same as murder. If they are ever successful at this, I would refuse it on God's moral grounds. It does not matter what excuses we make to justify our wrong actions. God's has spoken and His moral law is to be followed. If we follow His moral law, He will bless us. If we rebel, he promises judgment. It is a serious matter to kill a child.

Curt

It is very unlikely that fetal transplants will ever be used in HD again. Several people received them back in the late nineties, at a cost of $50,000 each - FOR AN EXPERIMENTAL TREATMENT. The results weren't positive.

Where HD research is going is with stem cells. My best guess is that restoration therapy will consist of the patients own adult cells, programmed to go back to the stem cell stage and to become neurons and with the genetic defect corrected. We have proof of principle in mouse studies.

Thank you, Marsha. That is good news. That is doable.

Curt