| Autor: |
Ramos S; Laboratorio de Citogenética, Instituto Nacional de Pediatría, 04530 Mexico City, Mexico. sera_ramos@yahoo.com.mx., Rodríguez R; Laboratorio de Citogenética, Instituto Nacional de Pediatría, 04530 Mexico City, Mexico. r-eb_ec-a@hotmail.com., Castro O; Laboratorio de Citogenética, Instituto Nacional de Pediatría, 04530 Mexico City, Mexico. castrum_1981@yahoo.com.mx., Grether P; Laboratorio DIAGEN, 05300 Mexico City, Mexico. pgrether@gmail.com., Molina B; Laboratorio de Citogenética, Instituto Nacional de Pediatría, 04530 Mexico City, Mexico. bertha_molina@yahoo.com.mx., Frias S; Laboratorio de Citogenética, Instituto Nacional de Pediatría, 04530 Mexico City, Mexico. sarafrias@iibiomedicas.unam.mx.; Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de Mexico, 04510 Mexico City, Mexico. sarafrias@iibiomedicas.unam.mx. |
| Abstrakt: |
Variation in the location of the 15p region D15Z1 is recognized as a polymorphism in several human populations. We used high-stringency Fluorescence In Situ Hybridization (FISH) to detect D15Z1 in a Mexican cohort. Here, we report the presence of extra D15Z1 sequences on the p-arm of acrocentric chromosomes other than 15 in two groups of Mexican couples, one with healthy offspring ( n = 75) and the other with aneuploid offspring ( n = 87), mainly trisomy 21. The additional D15Z1 polymorphism was significantly increased in individuals with aneuploid offspring (26.4%), in comparison to individuals with healthy offspring (14%). The most frequent acceptor chromosome of D15Z1 was chromosome 13p, followed by 14p, and finally, 21p. Our results show an overall frequency of 21.6% of this polymorphism in the Mexican population and suggest that its presence might be associated with the mis-segregation of other acrocentric chromosomes and aneuploid offspring. The high frequency of the polymorphism of the D15Z1 sequence on acrocentric chromosomes other than 15 suggests a sequence homogenization of the acrocentric p arms, related to the important function of the centromere and the nucleolar organization region, which flank satellite III DNA. |
