Laboratory of Molecular Endocrinology
Next Generation Sequencing in Pediatric Endocrinology
Molecular genetic testing of patients with inherited endocrinological diseases is performed to date with the Sanger sequencing of the probable gene indicated by the patient’s phenotype (hormone values, clinical characteristics, etc.) and existing literature data. When no abnormalities (mutations) are identified in the gene, analysis is continued on the next possible gene to identify the genetic cause of the disease. This methodology is expensive, time consuming and not always effective (low diagnosis rate) especially in diseases that show genetic heterogeneity.
Next Generation Sequencing (NGS) technology, developed over the last 10 years, allows multiple different DNA samples to be sequenced in parallel at the same time, in less time and at a lower cost than Sanger sequencing. This technology is based on:
- Whole Genome Sequencing (WGS),
- sequencing of all genome coding regions (Whole Exome Sequencing – WES),
- Sequencing of Genes Known to Be Associated with Genetic Diseases (Clinical Exome Sequencing – CES)
- and the sequencing of a targeted group of genes (Targeted Gene Panels), which are associated with a specific disease / phenotype.
In the Laboratory of Molecular Endocrinology of the First Pediatric Clinic are applied:
1) The NGS method in a targeted group of 15 genes which are associated with Monogene Diabetes Mellitus and Hyperinsulinism. This method allows us to test multiple genes simultaneously, in many patients, provides fast results, increases diagnostic accuracy, and has good cost-effectiveness compared to conventional sequencing methods.
2) The Clinical Exome Sequencing method, which allows the simultaneous analysis of approximately 4500 genes of the human genome, related to genetic diseases, on the Illumina platform (NextSeq-500), is applied to patients with inherited endocrinological diseases, which present genetic heterogeneity that is, they are linked to more than one gene.
3) The Exome Sequencing method, which allows the simultaneous analysis of all genes of the human genome (19000 genes), on an Illumina platform (NextSeq-500), is applied to patients with inherited endocrinological diseases, which show genetic heterogeneity, ie are associated with more of one genes.
The samples are sent after consultation with the treating physician and the patient or his guardian.