Personalized Medicine for the 21st Century

Personalized Medicine in the News

Making sense of SNPs and sequences

There have been multiple news articles and press releases recently regarding new companies that are offering products and services geared towards allowing the consumer to learn more about their “personal genome”.

Much of our genetic information (over 99%) is identical across all humans. So, it is the variations within our DNA that contribute in large part to the differences between us. “Genotyping” refers to the process of analyzing and recording the genetic variations within an individual’s genome. There are multiple ways genotyping can be done.

Navigenics, 23andMe and DeCODE are offering genotyping via analysis of single nucleotide polymorphisms, also known as “SNPs” (pronounced ‘snips’) that represent differences between single nucleotides, or base pairs, within our genetic code (DNA). SNPs are one kind of variation within DNA and are scattered throughout our genome. Most SNPs cause no differences in appearance / physical attributes or disease risk, but some do – and these are the ones that new personal genomics companies are going to focus on.

In contrast to SNP analysis, the company Knome is using a different genotyping method known as sequencing. Sequencing involves determining the order (or ‘sequence’) of letters of the genetic code along the length of a piece of DNA – including both the letters that do not vary among humans, and those that do. Knome is currently the only commercial company offering whole genome sequencing.

The table below gives an overview of the features of the products and services offered by each company – based solely on information we were able to glean from the company websites.

 

Company name

Navigenics

23andMe

deCODE

Knome

Name of the product / service (if different from company name)

Health Compass

 

deCODEme

 

Technology currently used

SNP analysis

SNP analysis

SNP analysis

Sequencing

# of SNPs currently analyzed

1 million

600,000

1 million

n/a

SNP chip provider

Affymetrix

Illumina

Illumina

n/a

Sample type

Saliva

Saliva

Buccal swab

Not specified

Are all results (data and/or currently available interpretation)) given to me when the initial analysis is completed?

Website is not completely clear on this; results (raw data) may be released to the customers with current subscriptions as relevant scientific studies are published

yes

yes

yes

Will I get automatic updates as new scientific information relevant to my genotype is learned from research?

yes - but only while you are a current subscriber (subscriptions are for one year)

yes

yes

Specific update services not clear from website: “Once your entire genome has been sequenced, you will be able to stay current on future genetic discoveries as they become available

Will my analysis provide information about the association of genetic variations with disease risk(s)?

The company website notes that SNPs analysis related to “about 20 actionable medical conditions” will be included. No list posted on the website yet.

Current analysis includes SNPs related to risk for:

o       Breast Cancer

o       Crohn's Disease

o       Heart Attack (Myocardial Infarction)

o       Multiple Sclerosis

o       Obesity

o       Prostate Cancer

o       Restless Legs Syndrome

o       Type 1 Diabetes

o       Type 2 Diabetes

o       Lactose Intolerance

o       Venous Thromboembolism

 

Current analysis includes SNPs related to risk for:

o      Age-related macular degeneration

o      Asthma

o      Atrial fibrillation

o      Breast Cancer

o      Celiac Disease

o      Colorectal Cancer

o      Exfoliation Glaucoma XFG

o      Inflammatory Bowel Disease

o      Multiple sclerosis

o      Myocardial Infarction

o      Obesity

o      Prostate cancer

o      Psoriasis

o      Restless legs

o      Rheumatoid arthritis

o      Type 1 Diabetes and Type 2 Diabetes

o      Lactose intolerance

The company website notes: “we will sequence your genome and will provide you with a comprehensive analysis of the results under the direction of a leading geneticist”

Does the company providing the service suggest that my results could be used to guide my medical care?

Yes – from their website: “The company will help people understand their genetic predisposition to

disease and arm them with information about what actions to take to help them stay healthy

No – from their website: “What we do not and will not do is provide medical advice to our customers” Further…” we have no way of evaluating our customers' health or medical needs, and we make every effort to clarify this for our customers

No – from their website: “We wish to emphasize that deCODEme is not a clinical service to be used as the basis for making medical decisions

Not clear from website

Is any consultation with a healthcare provider included in the cost of the service?

Yes- (a genetic counselor)

No

No

Yes- (participation of a ‘leading geneticist’ is mentioned – the amount of interaction nor what specific training this person will have is clear from the website)

Will I get any information on how my genes relate to my physical attributes?

 

Current analysis includes SNPs related to:

o       Bitter Taste Perception

o       Earwax Type

o       Muscle Fiber & Sports

Current analysis includes SNPs related to:

o       Hair & eye color

 

Will I get information about my genetic ancestry?

 

Current analysis includes SNPs related to:

o       Mitochondrial (maternal) inheritance;

o       Comparison of genetic similarity to people from different geographic regions

Current analysis includes SNPs related to:

o       Mitochondrial (maternal) inheritance

o       Y-chromosome (paternal) inheritance

o       More promised in the future at no additional cost

Not clear. Website notes: “beyond health-related applications, your sequenced genome can provide insights into your own ancestry and genealogy”

Will I be able to compare my genome to:

 

 

 

 

· Family

 

Yes – for relatives who have purchased the service also

Yes – for relatives who have purchased the service also

 

· Friends

 

Yes – for friends who have purchased the service also

Yes – for friends who have purchased the service also

 

· Celebrities

 

Yes- (including Marie Antoinette, Jesse James, Jimmy Buffet and Ben Franklin)

Yes- (only Craig Venter and Dr. James Watson at this point)

 

How much does it cost ?

$2,500 for the initial year subscription; $?? for subsequent years.

$999

$985 “Special introductory price”(additional features in the future may cost more)

$350,000 (the company is seeking 20 initial customers)

 

View a list of previous Personalized Medicine in the News articles.