ABSTRACT
OBJECTIVE: To determine the distribution of the CYP2C19*2 allele among Trinidadians. DESIGN AND METHODS: This is a cross sectional study among 100 patients attending primary health centers within the North Central Region of Trinidad. A stratified sampling technique was used in which there were three mutually exclusive subgroups: those of South Asian descent (Indo-Trinidadians), African descent (Afro-Trinidadians) and mixed ethnicity. Subsequently, systematic sampling was applied to each stratum to improve the representativeness of the sample. Hence, the 100 subjects recruited for the study were 40 Indo-Trinidadians, 40 Afro-Trinidadians and 20 of mixed descent. Apart from baseline data which included age, gender and ethnicity, DNA was assessed for the CYP2C19*2 allelic variant using a PCR method. RESULTS: There was a high allelic frequency (37%) for CYP2C19*2 which was found to be more common among Indo-Trinidadians (47.5%, 95% CI 32.0-63.0) compared to Afro-Trinidadians (22.5%, 95% CI 9.6-35.4) or people of mixed origin (45%, 95% CI 23.2-66.8). There was a significant difference (p=0.019) between CYP2C19*2 frequencies for Indo-Trinidadians and Afro-Trinidadians. CONCLUSION: We provided evidence that the prevalence of CYP2C19*2 mutation was high in our setting.
Subject(s)
Alleles , Platelet Aggregation Inhibitors , Trinidad and Tobago , MutationABSTRACT
Leucocin A is a class IIa bacteriocin produced by Leuconostoc spp. that has previously been shown to inhibit the growth of Listeria monocytogenes. A spontaneous resistant mutant of L. monocytogenes was isolated and found to be resistant to leucocin A at levels in excess of 2 mg/ml. The mutant showed no significant cross-resistance to nontype IIa bacteriocins including nisaplin and ESF1-7GR. However, there were no inhibition zones found on a lawn of the mutant when challenged with an extract containing 51,200 AU of pediocin PA-2 per ml as determined by a simultaneous assay on the sensitive wild-type strain. DNA and protein analysis of the resistant and susceptible strains were carried out using silver-stained amplified fragment length polymorphism (ssAFLP) and one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Two-dimensional SDS-PAGE clearly showed a 35-kDa protein which was present in the sensitive but absent from the resistant strain. The N-terminal end of the 35-kDa protein was sequenced and found to have an 83% homology to the mannose-specific phosphotransferase system enzyme IIAB of Streptococcus salivarius.
