The enzyme BChE (butyrylcholinesterase, also known as pseudocholinesterase) plays a role in the metabolisation of various drugs, such as certain muscle relaxants and local anaesthetics.
BChE is an enzyme that prevents toxic substances from reaching the nervous system. These include pesticides and neurotoxins, for example, but also natural toxins such as solanine, which is naturally present in the green parts of potatoes. Certain drugs are also metabolised by the enzyme BChE and thereby inactivated.
Genetic predisposition
The activity of the enzyme BChE varies from one individual to another.
This variation is partly explained by genetic variations in the BChE gene.
An underactive BChE enzyme can lead to muscle relaxants such as succinylcholine and mivacurium, and local anaesthetics like cocaine and procaine, building up in the body and causing side effects.
Such reduced activity, also known as pseudocholinesterase deficiency, occurs in around 1 in 2,500 people. In people with pseudocholinesterase deficiency the (respiratory) muscles may remain relaxed for hours, meaning that mechanical ventilation may be necessary for a long period.
When a genotype is determined these variations in the BChE gene are indicated by two so-called alleles. Each allele has a name consisting of a letter. An example of a possible BChE genotype is BChE\ U/U (U stands for Usual).
At iGene we determine the following variants (alleles) of the BChE gene:
A, F1, F2, K, H, J, S and other (classified as U).