Análisis de las variaciones en el número de repeticiones de 5 marcadores ancestrales en donadores recurrentes en México

Abstract

Microsatellites are highly polymorphic DNA sequences, consisting of short repeats, regularly from 1 to 7 base pairs, and over 70% of heterozygosity. The objective of this study was to obtain allele frequencies of 5 loci by capillary electrophoresis and comparing them with the Combined DNA Index System database (CODIS) to determine the effectiveness of the technique in the ancestral determination. Material and methodsDNA from 50 unrelated individuals (G1) was extracted. Six loci were amplified by PCR. The lengths of the markers were identified by capillary electrophoresis and the frequencies were compared with those reported in CODIS (G2) for Latin-Americans. ResultsThe frequencies of the polymorphisms, TH01 and D2S1338, were the only ones similar to those reported in CODIS. The number of alleles of FGA was different in both groups, and G1 did not have 4 of the reported alleles. The D18S51 polymorphism in G1 presented with a 10.2 allele unreported in CODIS, and lacked 4 alleles. For D16S539, our population values were different from those reported, 7 and 17 alleles were present in our population, but were not reported in CODIS. Moreover, alleles 14 and 15 reported in CODIS were not observed in our population. ConclusionsThe results of our study enable us to compare the frequencies of the polymorphisms in a sample of Mexican with other Latin Americans. The differences suggest the need to create databases of reference for our population, taking into account the race mixture that characterises us.