Genetic Testing

 

I’ve stated before that I’m kind of a nerd and that very science and medical related things excite me more than the normal person. DNA, genes, chromosomes…it’s all very interesting and confusing to me and I just want to READ AND LEARN ALL THE THINGS.

With genetic testing highlighted in the media recently due to Angelina Jolie’s reveal that she underwent a double mastectomy based on genetic testing results, I figured now was the time for this post.

A while back, a friend had her genome sequenced through a website called 23andme.com. Due to familial circumstances, she had many questions about her ancestry and health history. She posted a few of the results on Facebook and I instantly became curious. 

 

No need to poke fun, John, I was interested

My friend explained to me more in depth all the things she had learned through doing the sequencing and highly recommended that I purchase a kit and sequence my own genome.

So, I took the plunge and coughed up the $99 it cost to buy the kit.

And what a well spent $99 it turned out to be.

LB’s Top 10 Interesting Genome Sequencing Results

(In No Particular Order)

1)     I have a decreased risk of breast cancer

Reproductive cancers of all kinds (breast, uterine and ovarian) run on my mother’s side of the family from her paternal side; all of her aunts (my great-aunts) have developed one or more of the cancers I listed previously. Because of this familial link, my mother has been followed very closely at her doctor’s appointments and mammograms. Last year, I found a lump in my breast, which I’ve been following since then.

My lump is benign and my familial link to cancer is more distant, but the genetic components are still all there and scary to contemplate.

23andme.com doesn’t test for all the mutations located on the BRCA1 and BRCA2 genes, but it does test for three of the most common mutations linked to hereditary breast and ovarian cancers. I don’t have any of the three.

Based on the genomes of other Europeans, I’m only 10.8% likely to develop breast cancer in my lifetime compared to 13.5% of other users. Obviously, as with all genetic testing, it’s not a definitive no, but given my family history, I’ll take what my genes are telling me.

2)    I have a decreased risk of coronary artery disease

If the reproductive cancers plague the women in my family, coronary artery disease runs on my father’s paternal side of the family. My grandfather, in his lifetime, had a 5 vessel bypass (which is a significantly large number) and eventually ended up passing away from heart failure.

I always figured, “Great, if cancer doesn’t kill me, my heart will.”

Luckily, compared to other European genomes, I’m only 19.2% likely to develop CAD compared to the 24.4% of other users. That combined with recent foray into eating well and exercise, I’m kicking genetics in the ass.

3)    I don’t have the APOE ε4 variant of the APOE gene, which contributes to Alzheimer’s Disease

Huzzah!

I recently found this out and I thought it was exciting.

4)    I have an increased sensitivity to Warfarin (Coumadin) and Phenytoin (Dilantin)

If I were to ever have to be placed on either of these medications, I’d probably have to be on a smaller dose. Who knew!

5)    I am a carrier of Gaucher Disease

This result came from left field.

My mother has a recessive anemia disorder called Beta Thalassemia Minor. Being a carrier causes anemia, but two recessive copies passed down to children causes Beta Thalassemia Major and causes several health problems. My mother had both me and my brother tested at birth for either the major or the minor subgroups. We tested negative to both. All my life, that was the only genetic thing I thought I could possibly have.

Wrong, apparently.

Gaucher Disease is recessive and I only have one copy of the mutation, so I don’t exhibit the disease, but I could pass it along to my children. Which blows donkey chunks.

The mutation for Gaucher Disease is located on the GBA gene, which unfortunately leads to the fact that…

6)    I’m 4x more likely to develop Parkinson’s Disease

Awesome. My overall risk is 6.3% compared to the average of 1.6%.

My mother’s father (my Papa) had Parkinson’s Disease and it scares me that my genes could very easily tip me into craziness later in life. Thankfully, developing Parkinson’s is 27% attributable to genetics and a relatively rare disease. Also, there are certain lifestyle factors that decrease a person’s risk, such as drinking coffee and maintaining an active lifestyle.

Check and check.

Despite these worrisome results, genetics also are not the end-all-be-all.

7)     I’m 2.8% Neanderthal

All humans have some Neanderthal DNA within them. I’m proud to be 2.8% caveman!

8)    I’ve got French and Irish ancestors

For the longest time, all I knew was that I was 75% German and 25% Italian based solely on both sets of grandparents. I always envied those who could claim more than two ancestral roots.

Overall, I’m 99.9% European, which does not surprise me at all. But the breakdown is where I got excited. I’m 23.4% French and German; 7.8% British and Irish; 3.6% Scandinavian; 5.0% Greek; and 3.8% Italian. I’ve got a large smattering of nonspecific northern and southern European (which could mean several countries) and a tiny speck—0.1%--Sub-Saharan African.

I’m basically a European mutt.

9)    I’m part of the H1 haplogroup

All people alive on Earth can trace their mitochondrial DNA to one woman who lived 170,000 years ago and from her, the haplogroups formed based on migratory patterns subsequent generations followed.

The H1 haplogroup first appear 13,000 years ago and covers several regions including Europe, Near East, Central Asia and Northwestern Africa. Common theory is that during the Ice Age, glaciers forming over Scandinavia pushed people further south into France, Spain and Italy, thus forming the H1 haplogroup.

10) I share DNA with 608 other 23andme.com users

I have 608 relatives, most of whom share very little DNA with me, but still, somewhere along the way we share a common family member. Most of the 608 are distant cousins, but 7 of them 23andme considers second to third cousins and 48 of them 4^th cousins.

It’s humbling and mind blowing to think of how connected we all are.

If you have the opportunity to purchase a testing kit through 23andme.com, I highly recommend it. I've had my results since April and they're constantly updating your results based on new studies. And it's just fascinating to read. So many increase/decreased risk factors are attached to several genes and I still haven't read about all of them.

You also get access to all the raw data, which gives you links to other websites that describe the purpose and in-depth information on each gene. 

For all the information you get, it's definitely worth the $99 price tag.