Affiliations: AIDS Virus Research Laboratory, Department of
Microbiology, University of Venda, Thohoyandou, South Africa | Department of Biochemistry and Microbiology,
University of Fort Hare, Alice, South Africa | Department of Life Sciences, University of Buea, Buea, Cameroon | Department of Biochemistry, University of Pretoria,
Pretoria, South Africa
Note: [] Corresponding author: Pascal Obong Bessong, AIDS Virus Research
Laboratory, Department of Microbiology, University of Venda, PMB X5050
Thohoyandou 0950, South Africa. Tel.: +27 15 962 8301; Fax: +27 15 962 4749;
E-mail: bessong@univen.ac.za
Abstract: Data on genetic polymorphisms associated with response to anti-HIV
drugs has accumulated over the years. Information on how polymorphisms
influence drug metabolism and transport to target sites is important in guiding
dosage or selection of appropriate alternative therapies. This study determined
the frequency of MDR1 C3435T and CYP2B6 G516T polymorphisms associated with the
transport and metabolism of efavirenz and nevirapine, in a population of South
African HIV infected patients. In addition, association of polymorphisms with
immunologic and virologic factors was investigated. A 207bp of MDR1 exon 26 and
a 161bp of CYP2B6 exon 4 were obtained from patients by polymerase chain
reaction. Analysis of population-based sequences of MDR1 revealed a frequency
of 89% and 11% of C and T alleles respectively (n=197; X^{2} = 0.974; p=0.324).
Restriction fragment length polymorphism (RFLP) analysis of the CYP2B6 gene
revealed a prevalence of 9.5% of GG, 78.4% of GT and 12.1% of TT
genotype (n= 199; X^{2} = 65.204; p=0.00). There was no significant difference between immune recovery and decline
in viral load (n=53), with genotype after repeated
calculations of analysis of variance (ANOVA).
Keywords: HIV, MDR1, CYP2B6, polymorphisms, South Africa
