My dad's frontotemporal dementia left me traumatized. Genetic testing revealed I have a 99% chance of developing FTD too.

• Alyssa Nash was only 11 when her dad started exhibiting symptoms.
• She says she needed to know whether she would develop the condition.

This as-told-to essay is based on a conversation with Alyssa Nash. It has been edited for length and clarity.

When I was about 11, my dad started acting strange. At first, my family thought he was having a midlife crisis, even though he was only 38. As a child, what I remember most was trying not to step on my dad's toes since he had become a man who was quick to anger.

Doctors thought my dad had severe anxiety. For years, he was in and out of emergency rooms and psychiatric wards. At home, my mom took care of my dad, and I took on most of the chores that parents would do. I cooked a lot of meals and did all the laundry. School was my refuge. There, I kept my dad's health secret from everyone and pretended that I had a normal teenage life.

After seven agonizing years, my dad finally got a diagnosis: frontotemporal dementia, or FTD. The condition has been in the headlines this year after actor Bruce Willis was diagnosed. FTD impacts people at younger ages than other forms of dementia. It causes impulsiveness, trouble communicating, and personality changes, not the typical memory loss that we think of with dementia.

The diagnosis explained how my dad — who had been the sweetest, most beautiful soul — had changed so drastically. It also altered the course of my life.

I wanted to know my risk, even though there's no cure

I was 20 when my dad was diagnosed. Doctors explained that about 30 to 40% of FTD diagnoses, including my dad's, are caused by genetic mutations. As his child, I had a 50% chance of having the same mutation he had.

Immediately, I knew I wanted to get tested. I didn't want this to be a question mark for the rest of my life. I needed to know whether or not I had the gene mutation so I could be in control. Although there's no way to cure or slow the progression of FTD, knowing whether or not I had the mutation would help me make a plan of action for my life.

Looking back, I wish I had more genetic counseling before making this decision. Seven years ago, genetic testing was new and things have improved since then. Today, people who get genetic testing are encouraged to think about whether they want to be tested, and who should know the results. I didn't have that guidance.

I have a 99% chance of developing FTD

Tests showed I have the same mutation as my dad. That means I have a 99% chance of developing FTD, doctors told me.

Hearing that was devastating. I immediately put up a wall and barely told anyone. For seven years I went down a dark path. I dropped out of college, abandoning my plans to study art history and chemistry in order to become an art restorer. I hid behind alcohol for a long time.

This spring, I decided to make a change. I started seeing a therapist and was diagnosed with post-traumatic stress disorder (PTSD). I began to process my pain head-on. I'm looking after my mental health and my brain. All the right steps — therapy, processing, and self-care — are also the most painful. I'm so proud of myself for working hard to scrape and crawl out of the hole that my genetic testing results threw me into. It feels like I'm coming out of a fog.

I'm creating a beautiful life for myself

Since I know I carry the genetic risk for FTD, I'm participating in research studies to help change the future of this disease. Each year I go to the Mayo Clinic to get a spinal tap, MRI, and memory test. Every three months, someone comes to my house to collect a blood sample. Compared to the two-hour memory test, a blood draw is not bad at all.

When I do these things, I'm not thinking about myself. I can only live in the moment, not think about my future. But if I can help one person — truly one person — it will be worth it.

My dad is 53 now. He lives in a care facility more than two hours from where I live. His eyes light up when I see him, but he can't speak anymore. I haven't heard his voice in more than a year and a half, although I still watch old videos to hear him speak to me. The fact that he's still alive is bittersweet. You don't want anyone to live that way. You don't want to watch anybody live down that path.

I try not to think about being in his position. I have a tinge of hope, and I know I'm going to have the most beautiful future ahead of me. I dream of a bungalow with my dog and my painting supplies. I can't fear the future: I can just tell myself, "You're going to have the most beautiful life if you can just hold on a little longer."