Contestando a herança epigenética lamarckiana em mamíferos

quarta-feira, dezembro 16, 2015

Disputing Lamarckian epigenetic inheritance in mammals

Emma Whitelaw

Correspondence: Emma Whitelaw E.Whitelaw@latrobe.edu.au

Author Affiliations

Department of Genetics, La Trobe University, Bundoora 3086, VIC, Australia

Genome Biology 2015, 16:60 doi:10.1186/s13059-015-0626-0

Please see related article: http://dx.doi.org/10.1186/s13059-015-0619-z

The electronic version of this article is the complete one and can be found online at: http://genomebiology.com/2015/16/1/60

Published: 27 March 2015

© 2015 Whitelaw; licensee BioMed Central. 

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Abstract

A recent study finds that changes to transcription and DNA methylation resulting from in utero exposure to environmental endocrine-disrupting chemicals are not inherited across generations.

Epigenetic reprogramming

All mammals develop from a single cell, the zygote, which is made up of an egg and a sperm head, both of which contain a haploid genome. At the time of fertilization, the DNA of both egg and sperm is packaged into chromatin, and each has its own epigenetic (DNA methylation and histone modification) ‘state’ related to the previous functional requirements of these cell types. Once fertilization occurs, it is necessary that these epigenetic marks undergo extensive reprogramming for a complex multicellular organism to develop and differentiate. A similar period of extensive reprogramming of the epigenome has been shown to occur in the primordial germ cells during the development of the mature gametes. Some genes, called imprinted genes, are known to escape the epigenetic reprogramming in the early embryo and maintain the epigenetic state established in the gametes of the parents. This observation has supported the idea that perhaps some loci can escape both the reprogramming that occurs during early development and that which occurs during the development of mature gametes, thereby enabling Lamarckian inheritance. The evidence that this happens is scant, but has attracted much attention.

In a recent study published in Genome Biology, Iqbal and colleagues [1] have investigated the epigenetic changes that occur to the genome in response to endocrine disruptors and find that these changes are corrected by germline reprogramming events in the next generation.

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