NATIONAL DNA DAY Next Tuesday, April 25th, commemorates the completion of the Human Genome Project in April of 2003 and the discovery of DNA's double helix in 1953. One goal is to encourage students, teachers and the public to learn more about genetics and genomics. You can read more about it here. Two good links for your patients to learn or brush up their knowledge are: http://learn.genetics.utah.edu/ and https://ghr.nlm.nih.gov/primer The latter is a very current PDF booklet they can read or download called "Help Me Understand Genetics." CASE IN POINT A 29-year-old female with a clinical diagnosis of achromatopsia was referred to VisionAmerica of Birmingham for genetic testing. The result was that she was homozygous for a known pathogenic variant in the CNGB3 gene. There are five genes in which mutations can cause achromatopsia and more than 40 known mutations are in the CNGB3 gene. Therefore, what we really wanted for her was the exact diagnosis at the molecular level. We now have that. After she and I went over the report, we then looked at the website https://clinicaltrials.gov. There were 7 clinical studies listed for achromatopsia. Two of those were gene therapy trials for candidates with mutations in the CNGB3 gene. The eligibility criteria for one includes "... homozygous or compound heterozygous missense or null mutations in CNGB3." Eligibility for the other says candidates must have, "... documented mutations in both alleles of the CNGB3 gene." Wow - she is eligible for both! There are two lessons here - 1) As we celebrate National DNA Day, we are celebrating the achievement of a level of understanding that has led us to potential treatments for the underlying genetic cause of some hereditary eye diseases; 2) Diagnosis at the molecular level is quickly becoming standard of care and one of the reasons for doing genetic testing is to help our patients qualify for clinical studies in which they may wish to participate. We are right on the cusp of having effective treatments and one day, perhaps, even cures. This is so exciting and your patients with known or suspected hereditary eye disease deserve the opportunity to have genetic testing. If they don't quite understand why you want to refer them, an analogy I use goes like this: If you told me, "I have a car," my next question would be, "What kind of car?" If you told me, "I have achromatopsia," my next question would be, "What kind of achromatopsia?" That's what we want to find out - the actual diagnosis at the molecular (DNA) level. As the patient prepared to leave I told her, "You can call the coordinators of these two studies today to learn more and start considering if you might want to be a participant in either of these two trials." I'm not sure who was more excited, me or her! eyeGENE UPDATE Recall that eyeGENE offered free genetic testing but suspended accepting new patient samples over a year ago. I have about 13 folks who were enrolled before the cutoff who are still waiting on results. The long wait is primarily because of unanticipated Federal budgetary restrictions that have delayed testing. If you referred one of those patients you should have received a copy of a letter I sent to your patient inviting him or her to contact me if they would like to pursue testing from a different source. There are other options and I work with all patients, not just the eyeGENE ones, to find the best option(s) and to know their cost up front so they can agree or not before committing to testing. Generally speaking, the out-of-pocket cost for the patient has not been an obstacle very often with the exception of Medicaid, which does not cover genetic testing. There is however a new option for some patients - see next section. IDyourIRD (IDentify your Inherited Retinal Dystrophy) Speaking of cost, Spark Therapeutics has partnered with Prevention Genetics to offer free genetic testing for certain qualifying retinal dystrophies - specifically those that are progressive, non-syndromic and rod-mediated. No, not mediated by me (Rod) but by rod photoreceptors. This includes RP, LCA and choroideremia but, for example, would not include CSNB (it's not progressive), Bardet-Biedl syndrome (it's syndromic) or achromatopsia (it's not rod mediated). The test covers 31 genes, but those are high probability genes for the targeted dystrophies and the patient must agree to the terms and conditions for participation. https://idyourird.com/ I enrolled my first patient about 3 weeks ago. He was 12-years-old, the diagnosis was LCA and the insurance was Medicaid so genetic testing was not going to happen without this new program. AND... I expect that there will be FDA approved gene therapy for LCA and choroideremia this year. I'm hoping we find that he has a variant in the RPE65 gene because that will be a likely eligibility criterion for the initial approved therapy. Genetics at VisionAmerica The link that follows will take you to a brief overview of genetics and genetic testing at the VisionAmerica of Birmingham Center. You could provide this URL to your patients who might want a little more information about what we do. http://www.eyehealthpartners.com/genetic-testing/. Our website also has a nice series of bios for our very impressive MDs and ODs - good reading for your patients who may want to learn more about who you want them to see. Go to http://www.eyehealthpartners.com/doctors-birmingham.html. Smarter Every Day Yes, we can all get smarter with the really great CE from VisionAmerica and the annual August program is in the active planning stages right now. It will be another winner in this increasingly popular series. When I see you there, if you do not tell me how excited you are about what's happening with ophthalmic genetics, genetic testing and gene therapy - I'm checking you for a pulse!
0 Comments
Leave a Reply. |
AuthorThe staff and doctors at VisionAmerica are committed to providing relevant information for you, your patients and your practice. We hope you find the information in our blog post helpful. Archives
August 2019
Categories |