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Posts from the ‘genetics’ Category

Inherited Health: Building Family Trees

More than a year ago, I wrote about AccessDNA which now changed focus and became Inherited Health. Jordanna Joaquina, MS, CGC; Director of Genetics and Co-Founder of Inherited Health shared what kind of changes they implemented into the site:

  • We have created an easy to use and secure tool that allows people and their biological relatives to collectively create and update their family health history together
  • We then analyze the family history information to create a Personal Health Guide, which identifies hereditary disease risks and provide actionable guidance about how to lower these risks for each family member
  • We also provide a Summary of the family health history that can be printed and shared with doctors and helps avoid repeatedly filling out health history forms at doctors office and improves the accuracy of the information provided because of collaborative family effort

Click here to see a huge image that shows what a whole health report looks like with all the details and disease risks.

The Era of Personalized Medicine

It’s spectacular how fast this industry is changing. One example is Diagenic which offers peripheral blood-based diagnostic tests for breast cancer or Alzheimer’s disease (though it’s gene expression based). And now Medgadget reported about a new solution designed by Progenika BioPharma for Familial Lipoprotein Lipase Deficiency.

In collaboration with AMT, Progenika Biopharma has developed the LPLchip which detects mutations in the LPL gene, and has now received CE approval.

The chip can detect 120 different mutations in a sample of blood or saliva, enabling identification of patients who may benefit from gene therapy. So far, the picture for Glybera is looking good, with three studies showing a decrease in the incidence of pancreatitis, one of the most important complications of LPLD, in patients undergoing treatment. Expect to hear more about this in the future.

At this year’s Researchers’ Night, I talked about genomic medicine and I described the future of healthcare which would be personalized-centric and I said this era would come in around 10 years. It seems I was wrong and this transition will be much faster.

Whole Genome Sequencing in Diagnostics?

Using whole genome sequencing in diagnostics has been an issue for years, and as the cost of sequencing is rapidly declining, it seems it can pave the way for personalized medicine. A new research published in Genome Biology, Evolution of an adenocarcinoma in response to selection by targeted kinase inhibitors, just proves this point:

Adenocarcinomas of the tongue are rare and represent the minority (20 to 25%) of salivary gland tumors affecting the tongue. We investigated the utility of massively parallel sequencing to characterize an adenocarcinoma of the tongue, before and after treatment.

We conclude that complete genomic characterization of a rare tumor has the potential to aid in clinical decision making and identifying therapeutic approaches where no established treatment protocols exist. These results also provide direct in vivo genomic evidence for mutational evolution within a tumor under drug selection and potential mechanisms of drug resistance accrual.

DNA Dilemma on Newsweek

Mary Carmichael at Newsweek had a great series of articles focusing on direct-to-consumer genetic testing. An excerpt:

I’ve been following DTC genetics since 2007, when wide scanning first became available to the public. Since then, a number of writers have gotten wide-scale genetic tests and expounded on the results. Indeed, I sometimes wonder if I’m the last science reporter on earth with virgin genes. (Technical virgin: My doctor gave me a cystic fibrosis carrier test when I was pregnant.) Initially, I put off getting a full-genome scan because I wasn’t sure how useful such a test would be. I had no particular reason to take one, save curiosity. I wouldn’t expect to find anything serious and potentially life-altering like the Huntington’s disease gene in my results, because my family medical history is thankfully rather boring. The data most likely to be medically relevant to me would concern the genetics of common diseases, and at the time, many comprehensive and well-designed studies of those were still getting underway. I decided to wait a few years and see how research progressed. But here I am, three years later, still unsure.

Genetic Background of Social Drinking

Psychological Science, a journal of the Association for Psychological Science, published a very interesting paper focusing on the genetic background of social drinking. Specific gene variants might increase the risk for extensive alcohol use or abuse when spending time with heavy-drinking peers. An excerpt from Medical News Today:

Drinking alcohol increases levels of dopamine – a brain chemical that causes pleasure and makes us feel good. The dopamine D4 receptor gene (DRD4) has been shown to be involved in motivation of seeking out rewards. Research has suggested that carrying a specific form (or variant) of this gene – one that includes seven or more repeats of a certain section of the gene – may be associated with craving caused by alcohol-related cues. Psychological scientist Helle Larsen from Radboud University in The Netherlands and her colleagues wanted to investigate if this 7-repeat gene variant plays a role in how an individual responds to alcohol-related cues.

The results showed an effect between how much the confederate drank and the gene variant on volunteers’ alcohol consumption: When the confederate was seen consuming three or four drinks, carriers of the 7-repeat form of the gene drank more than twice as many glasses of alcohol than did noncarriers of the gene variant. However, when the confederate consumed only one drink, there was no difference in alcohol consumption between carriers and noncarriers. These findings suggest that individuals carrying this form of the DRD4 gene may be more sensitive than noncarriers to other people’s drinking behavior.

DNA Mutations in Real Time: Video

One of my favourite blogs, Spoonful of Medicine, just posted a great video which shows that mutations in E. coli bacteria can be tracked in real time. The method was published in Current Biology.

The key to this approach is using a fluorescent-labeled derivative of MutL, a protein involved in DNA mismatch repair. The accumulation of this fluorescent protein signals the occurrence of a mutation in a population of replicating E. coli bacteria. Even more significantly, this method allows the visualization of mutations that do not result in recognizable phenotypes. That means that it could be used to alert researchers to DNA errors they are not even looking for. The video below shows 180 minutes of E.coli growth compressed to 12 seconds:

National Society of Genetic Counselors: Interview with Elizabeth Kearney

Elizabeth Kearney, the President of the National Society of Genetic Counselors in the US, gave me an interview this weekend, and commented on how direct-to-consumer (DTC) genomic companies should provide their customers with genetic counseling, which is a crucial part in the whole process.

As President of NSGC, Liz Kearney is responsible for leading the association and serving as the chief spokesperson. Liz is committed to promoting the many benefits genetic counselors bring to other healthcare professionals and patients.  Liz received her genetic counseling degree from the University of Michigan in 1996 and practiced in a variety of settings, including prenatal diagnosis centers, a general genetics department, and a diagnostic laboratory.  She also earned an MBA from Northwestern University in 2006, and in 2007.

1) Recent news have been focusing on regulations around DTC genomic companies such as 23andMe, Pathway Genomics or Navigenics. How do you think DTC genomics should be regulated?

The NSGC would support regulation that requires the involvement of a qualified healthcare provider in ordering, interpreting, and delivering genetic information. In the mean time, the NSGC strongly recommends that consumers talk to a genetic counselor prior to having genetic testing to discuss what questions or concerns they have. A genetic counselor has specialized training in both medical genetics and counseling and will review a person’s family and medical history in light of the person’s specific questions to determine if there is appropriate testing available.

2) We, genetic bloggers, have been writing a lot about the potential problems with these genetic tests and the harm they can cause to laypeople. Is genetic counseling the solution for this?

Seeking genetic counseling prior to genetic testing is an excellent way to protect against potential harm to consumers who do not have much knowledge or experience with genetics. Sometimes tests will provide helpful information and sometimes the information is either not helpful or even alarming.

For example, if you have concerns about a history of diabetes, a genetic counselor would review the family history in detail before ordering any genetic testing. It may be that the family history is sufficient to raise concerns about your chances to develop diabetes, and then the genetic counselor would recommend you talk to your primary care doctor about regular diabetes screening. Additional genetic testing may only confirm what is already known (through reporting an increased chance) or falsely reassure you (through reporting a lower chance) because the genetic factors tested are not the ones causing diabetes in your family.

On the other hand, genetic tests can reveal powerful information. For example, a 30 year-old male with shortness of breath saw his doctor, who performed an ultrasound detecting a thickening of the heart muscle (hypertrophic cardiomyopathy). This thickening can be an inherited and treatable condition. The cardiologist worked with a genetic counselor to order the appropriate genetic testing, and the genetic counselor explained the positive results which allowed identification of other relatives at-risk to allow surveillance and earlier treatment. The testing may have helped save or prolong the lives of the individual and/or his relatives, but the doctor and patient needed the help of the genetic counselor to identify the right test for him and explain the results.

3) How can I contact a genetic counselor after ordering DTC genetic tests? As I can order such tests online, could I also contact genetic counselors the same way? What about patient privacy?

Patients who have DTC genetic testing can absolutely contact a genetic counselor to review the results afterward. You can find a genetic counselor by visiting www.nsgc.org, and clicking on the “Find a Counselor” link on the left-hand side of the homepage. The drawback of waiting to contact a genetic counselor until after ordering testing is that you may pay for genetic testing that is not helpful in answering your specific questions or may reveal alarming information that you weren’t expecting to receive.

Recent legislation, the Genetic Information Nondiscrimination Act (GINA), protects people from discrimination by their employer or insurer based on genetic information in the absence of manifestation of disease. Therefore, consumers can be comfortable sharing genetic test results with a genetic counselor or other healthcare provider if it is in the context of their medical care.

4) Genetic counseling is the most important part of the whole DTC genomics process. Do you think DTC genomic companies do their best to provide their customers with the possibility of speaking with a genetic counselor?

Each company is different, but consumers should look for companies that employ genetic counselors and strongly encourage or require speaking with a genetic counselor prior to genetic testing.

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