Pharmacogenetic analysis of inter-ethnic variability in the uptake transporter SLCO1B1 gene in Colombian, Mozambican, and Portuguese populations.

BACKGROUND: Statin-induced myopathy is reported to be associated with the solute carrier organic anion transporter family member 1B1 gene single nucleotide polymorphism, c.521 T > C. There is no epidemiologic data on this gene polymorphism in several countries. Therefore, this study aimed at assessing the genotype and allele frequencies of the gene variant in three countries.

METHODS: This study involved healthy individuals from Colombia, Mozambique, and Portugal. Genomic DNA was isolated from blood samples using the Qiamp DNA Extraction Kit (Qiagen). The isolated DNA was genotyped using novel Polymerase Chain Reaction-Restriction Fragment Length Polymorphism. Microstat and GraphPad QuickCal software were used for the Chi-square test and the evaluation of Hardy-Weinberg equilibrium respectively.

RESULTS: A total of 181 individuals' blood samples were analyzed. Overall, the TT (74.0%) genotype was the highest and the CC (7.8%) was the lowest. Country wise genotypic frequencies were Colombia 47(70.2%) TT, 12(17.9%) TC and 8(11.9%) CC; Mozambique 47(88.7%) TT, 5(9.4%) TC, and 1(1.9%) CC; and Portugal 40(65.6%) TT, 16(26.2%) TC, and 5(8.2%) CC. The reference (T) allele was highest among Mozambicans (93.4%) compared to Colombians (79.1%) and Portuguese (78.7%). Mozambicans showed statistically significant genotypic and allelic frequency differences compared to Colombians (p < 0.01) and Portuguese (p < 0.01).

CONCLUSIONS: Overall and country-wise, CC genotype was less frequent and it is relatively high for Colombians and Portuguese populations. This finding may imply statins risk-benefit variability associated with CC genotype among these populations that needs further understanding.