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Progressive Retinal Atrophy (PRA) is a family of inherited progressive degenerative eye diseases affecting the retina which ultimately result in blindness. Typically the first symptom of PRA is night blindness followed by increased reflectivity of the fundus or a “green sheen” to the eyes when viewed in dim light. There are several recognized forms of PRA and Mastiffs now have a DNA gene test available to them! The PRA DNA tests enable breeders to send in a blood sample and determine whether or not a dog has PRA or is clear (does not have the gene mutation for PRA) before the dog is old enough to develop symptoms. This also allows breeders to plan their breedings to avoid producing any pups that will be affected by PRA.

To see a list of PRA tests for other breeds go to OptiGen’s Test Page.

MCOA PRA Committee DNA Testing Recommendations
It is the recommendation of the MCOA PRA Committee that prior to breeding both the sire and dam is proven free of the dominant Mastiff PRA gene mutation either by DNA test or by having both parents proven free of the gene. For example, a Mastiff is proven clear of the PRA gene if:
  • both parents are DNA tested clear
  • or, both of the sire’s parents are DNA tested clear and the dam is DNA tested clear
  • or, both of the dam’s parents are DNA tested clear and the sire is DNA tested clear
  • or, all four grandparents are DNA tested clear
Please Only PRA & CMR DNA Test Your Mastiff with OptiGen
Over the past couple of years there have been other companies that have started advertising to use their Canine DNA tests at a reduced price.  Although the idea of saving money may be tempting, the MCOA Health Committee recommends that we continue to do our Mastiff’s DNA testing through OptiGen for several reasons.  
  • OptiGen has a clear track record of over 8 years of commitment to the highest quality service and have a proven record that gives owners the best assurance of accuracy along with prompt turnaround in genetic testing with excellent customer service.
  • OptiGen is absolutely committed to the science and understanding of the diseases detected by the tests that it offers. OptiGen works closely with the veterinary community to provide clients with the best possible information, education and genetic counseling on these diseases. Most of OptiGen’s tests were developed by scientists associated with OptiGen and are based on years of academic investigation into the disease being tested.  This is reflected in a complete understanding of what controls and descriptions are necessary to provide absolutely accurate information in the test report.
  • The scientists that work with OptiGen discovered the gene mutations that cause Progressive Retinal Atrophy and Canine Multi-focal Retinopathy in Mastiffs and they continue their investment in research to find new mutations and develop new DNA tests that will continue to provide breeders with the advantage of reliable, meaningful genetic information on their dogs. 
  • OptiGen has a close working relationship with the Mastiff Club of America’s Health Committee and the Orthopedic Foundation for Animals (OFA) and we recognize OptiGen’s intellectual property rights.  OptiGen also sends quarterly reports to OFA and the data is shared publicly to help our breed club and researchers stay informed of PRA and CMR statistics.
PRA DNA Test Clinics
Would your club be interested in holding a Mastiff PRA DNA Testing Clinic? If you are, please contact OptiGen and they will help you organize a clinic to receive a group discount.  For information on upcoming OptiGen Discounted Testing Clinics go to OptiGen’s website and click on Clinic Schedule.Before you host a clinic please contact OptiGen directly and go to their website for more information.  Here is a list of some of the information, but make sure you check with OptiGen first for approval to offer the discounted rates at your clinic and to verify the addresses and instructions are current.
DNA Test By Submitting A Blood Or Semen Sample

Blood is the gold standard for genetic research submissions and although OptiGen will accept cheek swabs for DNA testing they prefer to that we submit blood samples.  The blood is much better for quality control purposes as it yields more DNA and it can be used with current state of the art technology.  DNA from blood is also less likely to be compromised from cross contamination.OptiGen can extract a lot more DNA from a blood sample and they can offer long-term storage to their clients to use at a later date for research or as new DNA tests become available.  OptiGen also can archive a portion of the DNA submitted from blood samples for quality control purposes in case they need to go back and re-test a sample.  Semen will also yield more DNA than cheek swabs.Cheek swabs cost less and are more convenient, but the amount of DNA extracted from them is limited and there is a higher risk of contamination…  You can read more on the Concerns and Caveats of using cheek swabs on OptiGen’s website.So remember BLOOD IS BETTER for DNA testing and research!


If you would like to verify that a Mastiff has been PRA DNA tested through OptiGen go to the Orthopedic Foundation for Animal’s (OFA) website and search the OFA records for Mastiffs that have been PRA DNA tested. OptiGen sends updated quarterly reports to OFA to add to their database.OptiGen only provides the PRA DNA testing results on Mastiffs whose owners live in the United States.If you live outside of the USA and own a Mastiff that has been tested by OptiGen, please notify OptiGen and pay the appropriate fee to have your Mastiff’s results sent to OFA to add to their database.  


The MCOA PRA Committee, with Dr. Acland, undertook a breeding study to help determine the mode of inheritance of PRA in Mastiffs. The Study was based on a proposal written by Dr. Acland for the MCOA and peer reviewed by well known and respected PhDs in the field of DNA research. In simple terms the Study involved breeding a PRA affected Mastiff to a Beagle mix from Dr. Acland’s kennel that was known not to carry any PRA genes. The pups from this litter were placed in good homes with owners who made a commitment to the research and were willing to have Electroretinagrams (ERGs) done every six months until the pups were two years old. If any of the pups developed PRA then PRA in Mastiffs would be proven to be dominant – which is the case as two Meagles out of six developed PRA.

Exciting news!
Ch. Lamar’s Nut’n But Trouble was bred October 16, 1999! Many thanks to Trouble’s owner and breeder for their generous and unstinting support of the PRA Study. To the left is a picture of Trouble. The sire of the litter – a beagle mix from the Retinal Disease Study Facility known to be free of the gene for PRA.
The Rest of the Story
Mastiffs PRA DNA Test Available

In June 2001 OptiGen informed the MCOA PRA Research Committee that the Mastiff PRA DNA test was ready to go. OptiGen immediately started testing Mastiffs as soon as they made the announcement that the test was commercially available. The price of the PRA DNA Test is $130 (as of 12/1/2018). OptiGen provides an automatic 5% discount if you request a test online prior to having your vet draw and send in blood (Please be sure to print out OptiGen’s instructions and submission form for your veterinarian). In addition, when there are opportunities for Mastiff owners to send 20 or more samples at one time (such as from a testing clinic), OptiGen will offer a group discount of 20%.  They also offer other discounts throughout the year and you can go to their website to look at the current Discount Clinic Schedule.Additionally you may test for PRA, CMR, and DM through Wisdom Panel (
$149.99 (as of 12/1/2018) there are often discount codes on their website for $10 off. 

Mastiffs Providing Model for Human Retinitis Pigmentosa (RP)
The June 2002 issue of DVM News Magazine has an article titled “ENGLISH MASTIFF A MODEL FOR HUMAN EYE DISEASE” It states that the Mastiff breed is enabling scientists to help explain retinitis pigmentosa in humans. It is a joint study by Cornell Baker Institute for Animal Health and The University of Pennsylvania’s Scheie Eye Institute and was reported in the April 30, 2002 Proceedings of the National Academy of Sciences.The Scheie Eye Institute also shared an article on their website dated April 23, 2002 titled: “Dog Discovery a Major Step in Treatment of Genetic Blindness, Similarities between Humans and Mastiffs Pose New Hope for Observation, Treatment


 If your Mastiff is diagnosed with Progressive Retinal Atrophy or another hereditary eye disorder during a CAER exam we need you!


Please contact OptiGen and offer to submit a blood sample and a copy of the CAER exam sheet on your dog. 
OptiGen is interested in running PRA tests on affected dogs for FREE (at no charge) to the owners in order to be proactive in case a new mutation begins to cause another form of PRA in Mastiffs. 
OptiGen is also interested in doing further research to develop DNA tests for other eye diseases such as cataracts, so please continue to help OptiGen help Mastiffs! 
OptiGen has already developed a test for Canine Multi-focal Retinopathy in Mastiffs with the help of the Mastiff Community.  Please call and make arrangements with OptiGen to participate in their research

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