RESUMEN
In a collaborative work carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG), a polymerase chain reaction multiplex was optimized in order to type ten X-chromosome short tandem repeats (STRs) in a single reaction, including: DXS8378, DXS9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7133, GATA172D05, GATA31E08, and DXS7423. Using this X-decaplex, each 17 of the participating laboratories typed a population sample of approximately 200 unrelated individuals (100 males and 100 females). In this work, we report the allele frequencies for the ten X-STRs in 15 samples from Argentina (Buenos Aires, Córdoba, Río Negro, Entre Ríos, and Misiones), Brazil (São Paulo, Rio de Janeiro, Paraná, and Mato Grosso do Sul), Colombia (Antioquia), Costa Rica, Portugal (Northern and Central regions), and Spain (Galicia and Cantabria). Gene diversities were calculated for the ten markers in each population and all values were above 56%. The average diversity per locus varied between 66%, for DXS7133, and 82%, for DXS6809. For this set of STRs, a high discrimination power was obtained in all populations, both in males (> or =1 in 5 x 10(5)) and females (> or =1 in 3 x 10(9)), as well as high mean exclusion chance in father/daughter duos (> or =99.953%) and in father/mother/daughter trios (> or =99.999%). Genetic distance analysis showed no significant differences between northern and central Portugal or between the two Spanish samples from Galicia and Cantabria. Inside Brazil, significant differences were found between Rio de Janeiro and the other three populations, as well as between São Paulo and Paraná. For the five Argentinean samples, significant distances were only observed when comparing Misiones with Entre Ríos and with Río Negro, the only two samples that do not differ significantly from Costa Rica. Antioquia differed from all other samples, except the one from Río Negro.
Asunto(s)
Alelos , Cromosomas Humanos X/genética , Dermatoglifia del ADN , Etnicidad/genética , Genética de Población , Cooperación Internacional , Repeticiones de Microsatélite/genética , Reacción en Cadena de la Polimerasa/métodos , Mapeo Cromosómico , Costa Rica , Análisis Mutacional de ADN , Femenino , Frecuencia de los Genes/genética , Flujo Genético , Marcadores Genéticos/genética , Variación Genética/genética , Humanos , Desequilibrio de Ligamiento/genética , Masculino , Portugal , Control de Calidad , América del Sur , EspañaRESUMEN
A new polymorphic INDEL was detected at the X-STR GATA172D05 flanking region, which corresponds to an 18-bp deletion, 141 bp upstream the TAGA repeat motif. This INDEL was found to be polymorphic in different population samples from Native Americans, Africans, and Europeans as well as in an admixed population from the Amazonia (Belém). Gene diversities varied between 37.5% in Native Americans and 49.9% in Africans. Comparison between human and chimpanzee sequences showed that the ancestral state corresponds to the presence of two copies of 18 bp, detected in both species; and the mutated allele has lost one of these two copies. The simultaneous analysis of the short tandem repeat (STR) and INDEL variation showed an association between the INDEL ancestral allele with the shorter STR alleles. High diversities were found in all population groups when combining the information provided by the INDEL and STR variation. Gene diversities varied between 76.7% in Native Americans and 80.6% in both Portugal and Belém.
Asunto(s)
Mutación INDEL , Polimorfismo Genético , Secuencias Repetidas en Tándem , Cromosoma X , Animales , Cartilla de ADN , Frecuencia de los Genes , Haplotipos , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Grupos Raciales/genéticaRESUMEN
The 17 Y chromosome STR loci DYS19, DYS385, DYS389I and II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10 were analyzed in a male sample of 126 unrelated individuals from Rio de Janeiro. No shared haplotypes were observed, demonstrating the usefulness and informative power of these Y-STRs in male lineage identification in Rio de Janeiro. Pairwise haplotype analysis showed no significant differences in the comparison of Rio de Janeiro with Iberian samples from different regions of Portugal and Spain, as well as with other Caucasian samples from South America, namely Costa Rica, Buenos Aires (Argentina) and Sao Paulo (Brazil). The same set of Y-STRs was also typed in 119 father/son pairs and among 2,023 allele transfers, 8 mutations were observed with an overall mutation rate of 0.003955+/-0.001396 per locus/meiosis across the 17 loci. Except in one case, all mutations were single step. For DYS438 a four-step mutation was found which has never been reported before, where allele 10 mutated to allele 6.