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Updated: Aug 29, 2026

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
Frequency and enzyme activity of the butyrylcholinesterase K-variant in a Turkish population
Melih O Babaoglu1, Turgay Ocal, Banu Bayar
1Department of Pharmacology, Hacettepe University Faculty of Medicine, Sihhiye, 06100 Ankara, Turkey. babaoglu@hacettepe.edu.tr
Objective:
Among variants of the butyrylcholinesterase gene ( BChE), the K-variant causing Ala539Thr substitution is the most common one associated with about one-third reduction in the enzyme activity. This study aimed to detect the frequency of the K-variant allele in a Turkish population sample and also to evaluate how the plasma BChE activity was influenced by this variant.
Methods:
Patients administered for elective surgery ( n=77) were examined for the presence of the K allele. The enzyme activity was determined in plasma.
Results:
The K-variant of BChE is a common allele with a frequency of 0.266 (CI(95%) 0.196-0.336) in our sample from a Turkish population. Mean enzyme activity in subjects homozygous for the K-variant was about 40% lower than other subjects.
Conclusion:
The frequency of the BChE K-variant was significantly higher in a Turkish population than those reported for other populations and it is associated with a diminished enzyme activity.
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