Sequencing: Description, Indications, Preparation, Course of the Procedure, Results

Exome is a part of the genome responsible for protein synthesis in the body. The human exome corresponds to approximately 1% of the entire genome, or 30 million base pairs. However, mutations in the exome account for up to 85% of all disease-related mutations. For clinical purposes, in most cases, the data obtained as a result of reading the exome is sufficient.

The genome is the totality of all hereditary material contained in the cell of the organism. The human genome is built from DNA packed into 23 pairs of chromosomes (22 pairs of so-called autosomes and one pair of sex chromosomes) located in the cell nucleus. The human genome contains approximately 3.1 billion base pairs. Genome sequencing for clinical purposes is rarely used due to the high cost in relation to exome sequencing. In most cases, clinical problems are solved by exome analysis.

Data interpretation is the process of analyzing sequencing data to look for DNA changes associated with the subject’s health or potential risks to offspring. The results of data interpretation are reflected in the conclusion based on the results of exome or genome sequencing. To clarify the obtained sequencing results, it is recommended to consult a geneticist.

To be sure what kind of analysis is needed in your case, go through a preliminary consultation with a geneticist in person or remotely. This saves you the trouble of overpaying for genome analysis if exome data is sufficient for clinical purposes. You can sign up for a consultation with a geneticist by calling toll-free 8 800 250 90 75. You can get acquainted with geneticists in the corresponding section.

All analyzes performed at our site are interpreted and verified by three specialists, which ensures unrivaled research accuracy.

Sequencing by the NGS (next-generation sequencing) method is carried out on the latest devices of the latest generation from Illumina Inc, which allows getting a fast and very reliable result.

Why is exome sequencing necessary?

  • to assume or confirm (but not exclude!) the clinical diagnosis in controversial cases;
  • to clarify the prognosis of the course of the disease;
  • to clarify the hereditary genetic risk for family members;
  • to search for the “target” of prenatal and preimplantation testing.

Why is genome sequencing necessary?

  • to clarify the diagnosis in case of suspicion of a hereditary disease, when other diagnostic methods were not informative;
  • to identify mutations in the regulatory and other non-coding regions of the genome, which can be the cause of hereditary diseases;
  • to work on the search for new genes responsible for hereditary diseases.


  • For the study, it is necessary to donate blood from a vein;
  • On the day of the test, it is not recommended to eat fatty foods.

How is the service rendered?

  • Collection of a material for research – venous blood (at least 4 ml in a test tube with EDTA);
  • Isolation of DNA;
  • Preparation of DNA “libraries”;
  • Sequencing;
  • Bioinformatic processing of results (on request);
  • Conclusion of a geneticist – upon request;
  • Verification of the results – upon request;
  • “Library” – for parallel high-throughput DNA sequencing must be specially prepared. It needs to be “cut” into fragments of a certain length and attach a special label to each fragment, which is needed for several stages of direct sequencing in the device and subsequent processing of raw data.

Interpretation of results

To search for a presumptive hereditary disease (it is mandatory to provide an extract / conclusion from a doctor).

Based on the results of the analyzes, you will receive a bioinformatics conclusion and a laboratory conclusion with data on the technical characteristics and quality of the sequence.

Specialists analyze the sequencing results taking into account individual characteristics: family history, age of manifestation, medical examination data and other laboratory tests.

To interpret the test results, the patient and family members are advised to consult a geneticist.

Upon request, the patient or his/her legal representative can additionally be provided with:

  • File with “raw data” – sequencing results in .fastq format.