Rare Disease Day
Rare Diseases Day, which was first celebrated on the 29th of February in 2008 by the European Organization for Rare Diseases (EURORDIS), continues to be celebrated on the last day of February every year all over the world. What are Rare Diseases, which were also called Orphan Diseases in the past, because they are seen very rarely when evaluated individually and the diagnosis and treatment possibilities are very limited?
What are Rare Diseases?
The definition of Rare Disease varies from country to country. In Europe and Turkey, diseases that are seen in one or less frequency in 2000 people are called rare diseases. Diseases that occur with a frequency of one in 200,000 in the USA and one in 50,000 in Japan or less are considered rare diseases. The incidence of each rare disease varies around the world. While some rare diseases such as familial Mediterranean fever (FMF), Mediterranean anemia (Beta thalassemia) and Behçet’s disease are quite rare in many parts of the world, they are more common in countries with a coast to the Eastern Mediterranean, including Turkey. 80% of rare diseases are genetic. Although all genetic diseases are included in the Rare Diseases group, not every rare disease is genetic. Some very rare infectious diseases, autoimmune diseases and some cancers are in the non-genetic Rare Diseases class. Half of the patients are in the neonatal-childhood age and the other half are adult patients. Rare Diseases are clinically very heterogeneous. It affects many different tissues, organs and systems. They are chronic and progressive diseases. They cause serious physical and mental damage, often have no effective treatments and are fatal.
How Rare Are Rare Diseases?
There are nearly 8000 rare diseases described in the literature to date. This number is increasing every year. Although Rare Diseases are rare when looked at individually, when evaluated holistically, it is estimated that 10% of the entire world population is affected by rare diseases. There are approximately 30 million people in Europe, 25 million in the USA, and more than 350 million people in the world with rare diseases. It is estimated that around 5 million people in Turkey have Rare Diseases. A very rare group of Rare Diseases (less than 1 in 100,000) is called ultra rare disease. It is estimated that there are around 30,000 patients suffering from Ultra Rare Diseases in Turkey. In Turkey, where consanguineous marriage is more common than in European countries, it is predicted that Rare Diseases will become a bigger public health problem day by day.
Why Are Rare Diseases Orphaned?
The cause of 1/3 of Rare Diseases is unknown. Even in diseases of known cause, the diagnosis is mostly not made, patients are followed up with wrong diagnoses or the correct diagnosis is made too late. These diseases are not well known by physicians because they are very rare, clinically diverse and complex. The fact that the underlying cause is unknown in most of them, the lack of infrastructure and expensiveness of the tests that will provide the diagnosis makes it difficult for the patients to reach the diagnosis.
Only 5% of rare diseases can be cured. The diseases in the Rare Disease category have not attracted much attention of the medical and scientific world until recently due to the fact that they are very rare when evaluated on their own and the inadequacy of understanding the underlying causes of these diseases. For this reason, adequate studies have not been carried out on them, and their diagnosis and treatment opportunities have not been developed much. Awareness could not be developed both among physicians, in institutions that determine health policies, and in society as a whole.
However, since the beginning of the 2000s, the diagnosis of rare genetic diseases has become easier with the rapidly developing genetic analysis methods, the causes of these diseases have begun to be understood, and the development of new treatment methods has been paved. Today, it is possible to sequence the entire human genome and detect a single mutation within 3.2 billion bases, such as finding a needle in a haystack. Strategies for treatment have been developed as the underlying cause of the diseases has been understood. Techniques have also been introduced recently that will allow intervention at gene level disorders. Thanks to these techniques, treatment for some rare genetic diseases has become possible.
Status of Rare Diseases in Turkey-Problems and Solutions
Rare Diseases is a health problem that is getting worse day by day in Turkey. The frequency of autosomal recessive genetic diseases is considerably higher than in Europe and the USA, especially due to the high rate of consanguineous marriages. Although the number of Genetic Diseases Diagnosis Centers providing diagnostic services for Rare Diseases of genetic origin is increasing day by day, it is not sufficient enough for Turkey. Scientific studies on these diseases are extremely insufficient. Our country remains unfamiliar with the rapidly developing new gene therapy technologies in the world. New genetic therapy methods developed abroad and patented by foreign pharmaceutical companies are very expensive. Many of these treatments are not covered by the social security institution in Turkey.
In order to increase awareness of Rare Diseases in Turkey, innovations should be made in the education of medical faculties and other health professionals.
In order to develop new diagnosis and treatment methods for rare diseases, academic arrangements should be made to train highly qualified researchers and scientists in basic sciences such as biology, chemistry and physics, and basic medical sciences such as physiology, pathology and biochemistry.
Institutes that will conduct special research on rare diseases should be established.
The number and quality of genetic laboratories providing diagnostic services for genetic diseases should be increased.
Premarital carrier screening for rare genetic diseases that are relatively common, incurable, and result in death especially in newborns and childhood, as well as screening for newborns should be done free of charge.
Couples who are known to be carriers and at risk of having a sick child should be provided with the opportunity to have healthy children with free preimplantation genetic diagnosis methods.
It should be ensured that every couple considering pregnancy, especially those with consanguineous marriages, receive genetic counseling.
Some Rare Diseases Relatively Common in Turkey: Familial Mediterranean Fever, Behçet’s Disease, Down Syndrome, Duchenne Muscular Dystrophy, Phenolketonuria, Fragile X Syndrome, Spinal Muscular Atrophy, Multiple Sclerosis, Gonadal Dysgenesis Syndromes, Thalassemias, Familial Hypercholesterolemia Syndrome, Familial Tumor Susceptibility .
Rare Diseases Included in the Newborn Screening Program in Turkey: Phenylketonuria, Congenital hypothyroidism, Biotinidase deficiency, Cystic Fibrosis, Congenital adrenal hyperplasia
Pre-Marriage Screening Program in Turkey: Thalassemias, Hemophilia, Sickle cell anemia, Erythrocyte enzyme diseases
