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Elsevier, Rare, Available online 23 February 2023, In Press, Journal Pre-proof
It’s not rare to have a rare disease! 5-6% of the population or 300 million people worldwide are affected by a rare disease. There are more than 7,000 different rare diseases and genetic testing is a key instrument in diagnosing patients suffering from rare diseases as approximately 75-80% of rare diseases have an underlying genetic cause.