Low heritability in pharmacokinetics of talinolol: a pharmacogenetic twin study on the heritability of the pharmacokinetics of talinolol, a putative probe drug of MDR1 and other membrane transporters.
Efflux transporters like MDR1 and MRP2 may modulate the pharmacokinetics of about 50 % of all drugs. It is currently unknown how much of the variation in the activities of important drug membrane transporters like MDR1 or MRP2 is determined by genetic or by environmental factors. In this study we assessed the heritability of the pharmacokinetics of talinolol as a putative probe drug for MDR1 and possibly other membrane transporters.



Talinolol pharmacokinetics were investigated in a repeated dose study in 42 monozygotic and 13 same-sex dizygotic twin pairs. The oral clearance of talinolol was predefined as the primary parameter. Heritability was analyzed by structural equation modeling and by within- and between-subject variance and talinolol clearance was correlated with polymorphisms in MDR1, MRP2, BCRP, MDR5, OATP1B1, and OCT1.



Talinolol clearance varied approximately ninefold in the studied sample of healthy volunteers. The correlation of clearances between siblings was not significantly different for the monozygotic and dizygotic pairs. All data analyses consistently showed that variation of talinolol pharmacokinetics was mainly determined by environmental effects. Structural equation modeling attributed 53.5 % of the variation of oral clearance to common environmental effects influencing both siblings to the same extent and 46.5 % to unique environmental effects randomly affecting individual subjects. Talinolol pharmacokinetics were significantly dependent on sex, body mass index, total protein consumption, and vegetable consumption.



The twin study revealed that environmental factors explained much more of the variation in pharmacokinetics of talinolol than genetic factors.



European clinical trials database number: EUDRA-CT 2008-006223-31. Registered 26 September 2008. ﻿ClinicalTrials.gov number: NCT01845194 .
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany. johannes.matthaei@med.uni-goettingen.de.
Johannes
0000-0001-8118-0717
J
Matthaei
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
Mladen V
MV
Tzvetkov
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
Valerie
V
Gal
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
Cordula
C
Sachse-Seeboth
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
Daniel
D
Sehrt
Department of Epidemiology, Biostatistics and Biodemography, University of Southern Denmark, J. B. Winsløwsvej 9B, 5000, Odense, Denmark.
Jakob B
JB
Hjelmborg
Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, University of Tübingen, Auerbachstraße 112, 70376, Stuttgart, Germany.
Ute
U
Hofmann
Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, University of Tübingen, Auerbachstraße 112, 70376, Stuttgart, Germany.|Department of Clinical Pharmacology, University Hospital Tübingen, Auf der Morgenstelle 8, 72076, Tübingen, Germany.|Department of Pharmacy and Biochemistry, University of Tübingen, Auf der Morgenstelle 8, 72076, Tübingen, Germany.
Matthias
M
Schwab
Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, University of Tübingen, Auerbachstraße 112, 70376, Stuttgart, Germany.
Reinhold
R
Kerb
Institute for Clinical Pharmacology, University Medical Center, Georg-August University, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
Jürgen
J
Brockmöller
D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics; D015992:Body Mass Index; D005260:Female; D059647:Gene-Environment Interaction; D005838:Genotype; D006801:Humans; D008297:Male; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics*; D010597:Pharmacogenetics; D011412:Propanolamines / Q000493:pharmacokinetics*; D012737:Sex Factors; D018433:Twin Studies as Topic; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*
D018435:ATP Binding Cassette Transporter, Subfamily B; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D011412:Propanolamines; C513055:ABCB1 protein, human; C000715087:ABCC2 protein, human; C011550:talinolol
ABCB1; ABCC2; BCRP; Heritability; MDR1; MDR5; MRP2; P-glycoprotein; Talinolol; Twin study