Unexpected Associations with Parkinson’s

As part of Parkinson’s Awareness Month 23andMe is releasing the first of three surprising associations we’ve found between Parkinson’s and certain traits.

The associations are surprising because they appear so unrelated to the disease itself, but they may offer insight into the direction for future research.

Parkinson’s is a degenerative brain disorder, but sifting through the data 23andMe scientists have found associations with such things as personality types, joint pain and levels of cholesterol.

These associations may indicate true relationships between say, cholesterol metabolism and the development of Parkinson’s, or they may simply reflect some other underlying phenomenon. We don’t know yet, but we do know that other similar odd associations — such as some Parkinson’s patients developing a “sweet tooth,” or losing their sense of smell — have helped researchers diagnose and track the progress of the disease, which initially can be difficult. For instance, the loss of smell is associated with the loss of dopamine receptors in the brain, and it is an early indicator of the disease. The sooner Parkinson’s can be diagnosed the sooner treatment can start.

23andMe researchers looked at more than 1,000 different traits, conditions and diseases to find these associations with Parkinson’s. At the very least, they open up interesting directions for further inquiry.


  • sonya ,errill

    I was diagnosed with PD sbout 8 years ago and have slowly, very slowly, progressing with more issues such as balance, gait, memory, etc. I have read a great deal regarding the disease and the process but the sweet tooth was a surprise. I was never known to “enjoy” sweets being a “savor” type of gal but I did change about the time I turned 59. Then some of the other PD S and Sx started to appear at about 65 or so. PD is so varied with the signs and symptoms and we all progress differently. I have a friend who was dx 2 years after I was and she is progressing much more rapidly than myself. I think we all worry that our children will affected as well. It is such a “best guess”" disease for docs. Mine seem to think my precipitating factor was a serious head injury (should have died but didn’t), not familial. We all hope that research will help us find a way to recognize, prevent and slow progression/cure as much as possible. Altho’ I wish it did not take a popular celebrity(s) to be diagnosed with PD for greater public support. No one would want to wish that on anyone! Thanks for your interest and support!

  • Linda Kazazian

    I have Spasmodic Dysphonia AND Blepharospasms. When diagnosed with SD in 1993, I was told the SD was related to a defective gene on the 9th chromosome AND Parkinson’s frequently ran in the family. My mother and older sister also had blepharospasms. My mother had cousins who had Parkinson’s. My father’s side of the family had neither Parkinson’s nor blepharospasms or SD.

    In your studies of Parkinsons, have you accumulated any data on the relationship between SD, blepharospams and Parkinson’s?

    Can you identifiy the gene that shows the defect?

    • http://23andme.com Shwu

      Hi Linda,

      Both spasmodic dysphonia and blepharospasms can occur as symptoms of PD so there is definitely some overlap in the biology of these conditions. It’s possible there are genes that affect both the appearance of these disorders by themselves and their appearance as symptoms of PD. Our research has not focused on these other two conditions but it’s certainly a very interesting question! Thank you for reading.

  • richard

    what are these associations? is there a blog entry listing the 3 newly found associations? thanks, rll

  • Mark

    In your article about these associations, you show 9% had skydived, and 3% had had liposuction. It’s not clear to me what this means. What percent of the general population has done these things? Presumably it’s significantly different, but from just the numbers you give we can’t conclude any relationship of these traits with PD.

    • http://23andme.com Shwu

      Hi Mark,

      The charts in our Research Finding for personality traits and Parkinson’s are actually data from the general 23andMe database, rather than data specific to Parkinson’s patients. However, you are correct that the percentages are significantly different in Parkinson’s patients compared to the rest of the database.

  • Alice

    Is there any connection between Parkinson’s meds and weight gain? I am on Mirapex, Amantadine and Azilect. Prior to my diagnosis I lost 44 pounds on Jenny Craig. I am still on the plan and have gone up 2 sizes since my diagnosis in December. I seem to be retaining some fluids. It seems like all of a sudden my pants didn’t fit and I had to get 2 sizes up. I am not eating sweets. Very disheartening.

  • richard

    thank you, shwu, rll

  • Ari

    My father was diagnosed with PD and interestingly he mentioned that he had lost his sense of smell a few years before his diagnosis.

  • Araneus

    Loss of the sense of smell is well-known to be associated with Parkinson’s. The olfactory bulb contains doapmine neurons, which get damaged and die just like those in our mid-brain. But unlike the mid-brain, the olfactory bulb constantly replaces cells: and there is some evidence that in Parkinson’s this system goes into overdrive, and it is too many dopamine neurons that cause the loss of the sense of smell, not too few (e.g. Mundinando et al, Acta Neuropathol. 2011 Jul;122(1):61-74. Epub 2011 May 8: http://www.ncbi.nlm.nih.gov/pubmed/21553300. Sadly, experts tell me that the olfactory dopamine neurons aren’t the same as the ones in the mid-brain, so you can’t just transplant a few stem cells.

    On cholesterol, I can’t find any papers to back it up, but my theory is that, since cholesterol is the basis of synthesis of all steroids, such as oestrogen, and oestrogen in the brain is currently being explored as a possible neuro-protective agent to treat PD, then our bodies are actively producing more cholesterol (which can pass through the blood-brain barrier) to stimulate oestrogen (which can’t) production in the brain.

    As for joint pain, I’ve no idea – but I’ve had Parkinson’s for 6 years, and have had a lot of mild to moderate joint pain in the past 2 years in particular.

  • Suzy Parker

    I am wondering if anyone ever answers these questions…it would be nice to see some answers! Please and thank you!

  • http://Facebook Marcia Priddy

    My husband was diagnosed with PD about 6 years ago. For about 2 years before that he was complaining about his hips bothering him when he played golf and blamed it on arthritis. Also about that time is when we noticed his sense of smell was gone.He also has started to crave sweets and he never was a sweet eater.
    Craving and addictions are part of PD. We are now going into the Parkinson’s dementia. Every case is different. My husband does not have the tremors like many do but his confusion is getting much worse. God bless all or you.

    • Leila

      Hello, my husband was diagnosed with PD a few years ago and was put on several medications…I noticed he was complaining about back and hip pain, craving sweets terribly, loss of appitite, gait and balance and shuffleing.,drooling, nose running….and then I checked out all of his medications and found that several had negative side effects….I spoke to dr. and showed him (neurologist) and he too checked into this…I was then told my husband had medication induced pd….and he was taken off all meds..weined and started them in other mgs, and so on…What a difference…So much better…thenall ofa sudden I noticed he was ok almost normal one day, and then the next day…he was pitiful…Dr. said because he is not taking meds at the same time every day he is experiencing highs and lows. So I am now in control of his meds. His tremors are worse, and the sweet craving is present but he drives, walks, bathes, dresses does everything himself. Ifeel so bad for him, because you just never know from day to day what will trigger him to have a personality moment….I just have to say that all of you with PD or living and or caring for someone with pd…GOD BLESS YOU, you are in my thoughts and prayers.

  • Claudia

    The only symptom mentioned here I remember was that my husband had loss of sense of smell. Actually he complained that everything smelled like vanilla for several years before his diagnosis. His cholesterol levels were at the high end of normal but not excessive. No joint pain that he complained of. I remember him saying “I used to laugh all the time. Now I rarely laugh. I don’t know why.” I asked him if he felt depressed or sad, especially since the death of his dad who he was really close to. He said that was not it. We talked about whether he was happy with our life and he said he was very happy. He felt that he had done everything that he had every wanted to do. I suspect that was another PD symptom, kind of a suppression of emotion. As the disease progressed he cried easily though at appropriate times. We did not get a PD diagnosis until 1 year after heart surgery, which was completely unexpected. Cardiologist said his BP & cholesterol would not have been considered high a year earlier, and were not excessively high. His cardiologist noticed PD symptoms and referred him to neurologist for diagnosis 1 year later. He died 6 years after diagnosis, PD was slow and steady. Meds didn’t help. We even tried shunt surgery for possible hydrocephalus. He never experienced tremors. Started with facial masking, incoordination. Eventually aphasia, dysphasia, and all the rest.

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