Page 84 - The prevalence of the Val66Met polymorphism in musicians: Possible evidence for compensatory neuroplasticity from a pilot study

Validation of genes in childhood obesity | 7

rs10767664 A-allele (25) and NEGR1 rs2815752 detect the influence of the genetic component in this
A-allele (26,27). Regarding BDNF,Zegers et al. complex phenotype in childhood, where environmen-
screened the coding region of the gene and did not tal exposure and its interaction with genotypes have
find mutations associated with overweight or obesity occurred for a relatively short period of their lifetime.
in children and adolescents (28). On the other hand, The continuity of the follow-up of the two cohorts
Gardner et al. revealed BDNF promoter methylation may, in the future, bring more important findings in re-
levels associated with satiety responsiveness in female lation to these questions.
children (29). ORIGINALRESEARCH
In our study, we found SEC16B rs10913469 T/T
genotype associated with increased energy, carbo- Conflict of Interest
hydrates and lipids intake. Other studies also in pae- Statement
diatric samples observed the C-allele associated with
No conflict of interest was declared.
BMI and risk of obesity. The minor allele for this SNP
was found in our sample with a lower frequency than
in European-derived (CEU) or African (YRI) population Acknowledgements
samples (Table 2). Therefore, these discrepancies
M. R. Z. carried out the experiments, the statistical
may be due to population heterogeneity and/or differ-
analyses and wrote the manuscript. C. S. performed
ent linkage disequilibrium patterns. It is important to
nutritional evaluation and database construction. P.
notice that the individuals studied herein are all from
D. B. C. and M. R. V. were responsible for the cohort
Rio Grande do Sul, the Brazilian southernmost state,
selection, nutritional evaluation and sample collec-
where the Amerindian and African influence is
tion. S. A. participated in the statistical analyses and
reduced in comparison with all other geographic
manuscript writing. V. S.M. conceived the experi-
regions from Brazil. One striking difference between
ments, analyzed and interpreted data and wrote the
Brazil and other countries that congregate European
manuscript. All authors approved the final version.
and African descents, like the USA, is the high degree
This work has been financially supported by grants
of admixture that can be found between these eth-
from the Conselho Nacional de Desenvolvimento Ci-
nicities, making very difficult to determine ancestrality
entífico e Tecnológico (CNPq, Brazil) and the
from phenotypic characteristics (30). Therefore, the
Fundação de Amparo à Pesquisa do Estado do Rio
finding that most gene variants presented intermedi-
Grande do Sul (FAPERGS, Brazil).
ate frequencies between Euro and Afro descendants
was expected.
A limitation to our study is that our moderated sam- References
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