Diagnostic possibilities in clinical genetics today and how to interpret the findings
DOI:
https://doi.org/10.13112/pc.1042Keywords:
GENETIC TESTING, CHILD, HIGH-THROUGHPUT NUCLEOTIDE SEQUENCINGAbstract
The development of medical genetics has led to its integration into almost all areas of medicine. The clinical picture of a genetic disorder is most often recognized in childhood. Some genetic disorders may also be rare diseases and recognition "from phenotype to genotype" is highly complex due to the tremendous clinical heterogeneity. In addition to the fact that clinical features can be variable within a single gene mutation, symptoms, often non-specific, can change depending on the child's age, and the phenotype can vary even within the same family. Most patients with complex disorders require a multidisciplinary approach and a combination of many diagnostic procedures to determine all the clinical features of the disease, all of which are time-consuming and expensive. When we perform an extended clinical work-up and detect deviations that raise a diagnostic suspicion, we need to choose one of the diagnostic genetic tests to confirm the diagnosis because confirmation usually represents the end of a diagnostic odyssey that can, sometimes, last for years. In everyday clinical practice, the complexity of diagnosing genetic disorders arises from genetic variability and the heterogeneity of the clinical picture, but also from the insufficient number of clinical geneticists and lack of clinical experience, coupled with the limited availability of genetic testing in our country. Defining clinical indications and guidelines is essential for the effective application of old and new genetic testing technologies in everyday work. In addition, good multidisciplinary cooperation is necessary between the physician who refers the patient for genetic testing, the clinical geneticist, the laboratory medical geneticist, and physicians specializing in individual specialties.
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