How is a genotype test carried out

SLCO1B1 Genotyping (SLCO1B1)

SLCO1B1 genotyping is a medical laboratory test from the area of ​​so-called pharmacogenetics. This involves examining a connection between hereditary factors (genetic variations) and the effectiveness or toxicity of certain drugs. In the case of SLCO1B1 genotyping, genetic traits are specifically examined that can influence treatment with statins (drugs that lower the cholesterol level in the blood).

In order for drugs from the group of statins to be effective, these drugs must be absorbed into the interior of the liver cells via a certain protein (a so-called transport protein in the cell membranes):

  • SLCO1B1 transport protein.

Certain genetic SLCO1B1 variations can lead to the inhibition of the uptake of statins into the liver cells, in which case these drugs can cause serious side effects in the affected patient:

  • Rhabdomyolysis (disintegration of striated muscles of the musculoskeletal system and the heart);
  • Kidney failure.

In these cases, if certain SLCO1B1 genotypes are positively detected, the treating doctor must carry out a corresponding risk-benefit assessment before treatment with statins.

The adaptation of a drug therapy to the metabolism of an individual is referred to as personalized or individualized medicine, with certain hereditary characteristics also being taken into account in this context. For this reason, SLCO1B1 genotyping in the run-up to a planned therapy with a statin with regard to potentially toxic side effects of a drug from this drug group is an important diagnostic measure.

SLCO1B1 genotyping is a special laboratory medical procedure for analyzing certain gene variations (so-called alleles) in this molecular transport protein system. All that is required for this genetic test is a simple blood draw. In the medical laboratory, the genetic material (so-called deoxyribonucleic acid - DNA) is extracted from the blood, the corresponding gene region is multiplied (read: "amplified") in the laboratory process of the polymerase chain reaction (PCR) and, in the case of positive detection, the sought gene variant identified or quantified.

In addition to the PCR process, there is also the possibility of deciphering the exact sequence of the patient's genetic code. This testing method is called "DNA sequencing". Since this laboratory method is more complex than the PCR process, DNA sequencing is carried out as part of the SLCO1B1 genotyping, especially in connection with special diagnostic or scientific questions.