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Objective: To describe the population structure of the 48‐bp variable number of tandem repeats (VNTR), located in exon 3 of the dopamine receptor D4 gene (DRD4), in 41 Tarahumara from northern Mexico, 20 Mixe from southern Mexico, and 169 people from Mexico City. Methods: Genotypes for the DRD4‐VNTR were determined, from which 15 Tarahumara, eight Mixe, and 37 urban homozygous individuals were sequenced. Repeat‐allele frequencies were compared with other world populations. Results: The DRD4‐VNTR variation in Mexico City appeared similar to the world mean. For the Mixe and Maya, DRD4‐VNTR diversity appeared closer to South American groups whereas the Tarahumara were similar to North American groups. People from Mexico City and the Mixe exhibited attributes of a large and admixed population and an isolated population, respectively. The Tarahumara showed endogamy associated with a substructure as suggested by a preliminary regional differentiation. For the DRD4‐VNTR and/or the adjacent 5′‐173 bp sequence, the three populations exhibited negative Tajima's D. Two new VNTR haplotypes were discovered: one in Mexico City and another among the Tarahumara. Conclusions: A differentiation in the DRD4‐VNTR of global relevance occurs between northern and southern populations of Mexico suggesting that the Mexican Trans‐volcanic Belt has been a major frontier for human dispersion in the Americas. Ancient trespass of this barrier appears thus related to a major change in the population structure of the DRD4‐VNTR. Distinctive and independent patterns of DRD4‐VNTR diversity occur among the two Mexican indigenous populations by a still undefined combination of drift and selection. Am. J. Hum. Biol. 26:682–689, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective To describe the population structure of the 48-bp variable number of tandem repeats (VNTR), located in exon 3 of the dopamine receptor D4 gene ( DRD4), in 41 Tarahumara from northern Mexico, 20 Mixe from southern Mexico, and 169 people from Mexico City. Methods Genotypes for the DRD4-VNTR were determined, from which 15 Tarahumara, eight Mixe, and 37 urban homozygous individuals were sequenced. Repeat-allele frequencies were compared with other world populations. Results The DRD4-VNTR variation in Mexico City appeared similar to the world mean. For the Mixe and Maya, DRD4-VNTR diversity appeared closer to South American groups whereas the Tarahumara were similar to North American groups. People from Mexico City and the Mixe exhibited attributes of a large and admixed population and an isolated population, respectively. The Tarahumara showed endogamy associated with a substructure as suggested by a preliminary regional differentiation. For the DRD4-VNTR and/or the adjacent 5′-173 bp sequence, the three populations exhibited negative Tajima's D. Two new VNTR haplotypes were discovered: one in Mexico City and another among the Tarahumara. Conclusions A differentiation in the DRD4-VNTR of global relevance occurs between northern and southern populations of Mexico suggesting that the Mexican Trans-volcanic Belt has been a major frontier for human dispersion in the Americas. Ancient trespass of this barrier appears thus related to a major change in the population structure of the DRD4-VNTR. Distinctive and independent patterns of DRD4-VNTR diversity occur among the two Mexican indigenous populations by a still undefined combination of drift and selection. Am. J. Hum. Biol. 26:682-689, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Previously we report long lasting effects on ovary of mice prenatally exposed to flunitrazepam (FNZ), a benzodiazepine with tranquilized action. In this work we find that the FNZ don't prevent the effects on ovary prenatally exposure to stress in mice. We studied adult females born from mothers that had been stressed by immobilization on day 6 ofgestation (GD-6) or group S, and from mothers stressed also by immobilization at GD-6, but which received a single oral dose of FNZ immediately after the stress group FNZS. The control groups were the SS that received the GD-6 saline solution and the group NT non-treated. Their ovaries were extracted for histology studies and to observe the activity of 3b hydroxysteroid dehydrogenase/isomerase (3 b-HSD). The histological analysis revealed high staining affinity ovarian cell of S and FNZS. Double oocytes and apoptotic bodies were found in the secondary atretic follicles, as well as abnormal primordial, primary and secondary follicle populations, as compared to SS and NT groups. The primordial, primary, and secondary follicles were significantly reduced in the experimental groups. But the primary and secondary atretic follicles were higher in both groups, and the number of corpora lutea was lower in both groups. The activity of 3 b-HSD was abnormally increased in both FNZS- and S-groups. These findings suggest that FNZ did not counteract the impairing effects of prenatal stress on adult offspring ovarian follicles, and could rather be responsible for long lasting changes occurring during embryonic programming. [ABSTRACT FROM AUTHOR]