Frecuencias genotípicas y alélicas de apolipoproteina e (APOE) en una muestra de adultos en Bogotá

Introduction: apolipoprotein E (APOE) is a glycoprotein involved in the transport of lipid molecules. Three alleles of the APOE gene have been described: Ɛ2, Ɛ3 and Ɛ4. Several studies show an association of the APOE isoform with late-onset Alzheimer´s disease. Objectives: to determine the genotypic and allelic frequencies of the APOE gene in an adult sample in Bogota. Materials and Methods: a cross-sectional observational descriptive study. Genomic DNA was extracted from a peripheral blood sample and APOE alleles and genotypes were determined using the PCR tetra-primer method. Results: we included 1254 subjects, 942 women (75%) and 312 men (25%) aged between 40 and 100 years. The most frequent allele was Ɛ3 (85%), followed by Ɛ4 (11%) and Ɛ2 (2%). Of the population that declared to have Cundinamarca and Boyaca sub-regions ancestry, 567 subjects (74.6%) had genotype Ɛ3/Ɛ3, while 156 (20.4%) had Ɛ3/Ɛ4, 23 (3%) Ɛ2/Ɛ3, 11 (1.5%) Ɛ4/Ɛ4 and 4 (0.5%) had genotype Ɛ2/Ɛ4. The individuals with genotype Ɛ2/Ɛ2 declared not to know the data on their ancestry. Conclusions: the allelic and genotypic frequencies of APOE vary according to ethnic origin. However identifying subjects with the less frequent genotype (Ɛ2/Ɛ2) is possible when analyzing larger samples. In previous reports in the country, genotype Ɛ2/Ɛ2, has not been described and was identified in the present sample as the one with the lowest proportion.