General | 11 October 2018

Genetic testing for IRDs varies widely across the RI membership

In order to understand the current status of the genetic testing pathway for IRD patients, we asked our members what the experiences are in their countries. Nine respondents from both EU and non-EU countries revealed disparities in test type availability, access and payment options. (Italy, Austria, Poland, Germany (two replies), Ireland, Iceland, Brazil, South Africa).

While it revealed that patients in some countries have access to genetic testing, this is not the norm in most countries. Staffing and funding shortages were highlighted in all countries, with a persistant overreliance on research programmes noted.

Given the recent FDA and EMA approval of gene therapy for biallelic RPE65 LCA, it is shocking that none of our respondants could tell us how many people in their country would be eligible for this therapy due to a complete lack of data.

Therefore, we at Retina International see a great need for governments to provide clincial-grade genetic testing and counselling to patients with IRDs in order to obtain a genetic diagnosis, without which access to clinical trials and new gene therapies is impossible. Please see our RED ALERT Toolkit for more information on genetic testing for IRDs. 


Summary of Genetic Testing Survey of RI Members 2018:


1. What types of genetic testing are used in your country?

We asked our members what types of genetic testing are used in their countries for research-grade or clinical-grade testing of inherited retinal diseases.

Main points on ‘Frequency of Testing’:

  • Simpler ‘Panel’ and ‘One Gene’ tests are much more commonly used across the board than more complex but potentially more informative ‘Whole Genome’ or ‘Whole Exome’ testing.
  • Some countries (Germany, Italy, Ireland, Austria) have access to all types of testing, while others (Poland, Iceland, Brazil, South Africa) have access to 1 or two types.
  • ‘Panel’ testing is the most frequent type for both clinical and research grade across all countries, especially in non-EU countries Iceland, Brazil and South Africa where it dominates.
  • ‘One Gene’ testing is the next frequent with 77% of countries reporting it at high frequency.
  • ‘SNP’ testing is found in 55% of respondent countries but not used as frequently as ‘Panel’ or ‘One Gene’
  • ‘Whole Genome’ and ‘Whole Exome’ testing are conducted in EU countries but are the least used of all the tests. In non-EU countries, ‘Whole Genome’ and ‘Whole Exome’ testing is rarely used.


2. What is the referral pathway to access genetic testing in your country?

The various routes to access genetic testing differ between countries and also within countries.

Main points:

  • For every country, the first step is usually a referral or application by an ophthalmologist. But this is where the similarities end.  Self-referral is rare but happens. 
  • The referral from the ophthalmologist may next go to
    • a health insurance company for approval, or
    • a medical geneticist, or
    • a national genetics clinic, or
    • a private genetics clinic, or
    • a research programme
  • The approval for a genetic test is then obtained from one of the above and the test carried out.


3. Who executes the genetic testing?

Main points:

  • Clinical-grade tests, which require accredited human genetics labs, are generally processed in different centres than research-grade tests.
  • EU countries were more likely to conduct clinical-grade genetic testing locally in local, nationally funded hospital-based labs or centres, while non-EU countries such as Brazil were reliant on privately funded labs or sending samples to other countries.
  • Research-grade tests are conducted in research institutes or research hospitals.


4. Who pays for the genetic testing?

Main points:

  • Non-EU respondents rely moreso on self-payment or non-profit funding
  • In most EU countries that replied, clinical-grade tests are conducted through the national health system and so are paid by public healthcare or health insurance. However, some patients still pay privately.
  • Industry or research funding pays for research-grade testing or those related to clinical trials.


5. What is the incidence in your country of people with a genetic diagnosis of the RPE65 mutation?

Main points:

  • All but one respondent replied that the incidence of mutations in the RPE65 gene is unknown as there is no data.
  • Brazil was the only country to have data on incidence of RPE65 mutations. In a 2017 study on 30 Brazilian families with LCA, 17% of a subset of probands were shown to have mutations in the RPE65 gene.


6. Any other information about access to genetic testing in your country that you would like to share?

Main points

  • Waiting time to get an appointment for genetic testing can be substantial
  • Turn-around time for getting results can be very slow and is linked to personnel shortage in labs
  • Shortage in key staff such as genetic counsellors and clinical geneticists
  • An overreliance on research institutes and patient organisations to fund and provide genetic testing


If you would like to contribute information to this survey, it is not too late. Please contact and we would be delighted to supply you with the survey. 

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