Journal of Genetics

, Volume 97, Issue 2, pp 371–378 | Cite as

Epigenetics with special reference to the human X chromosome inactivation and the enigma of Drosophila DNA methylation

  • Deepti DeobagkarEmail author
Review Article


Epigenetics confers adaptability and survival advantage to an organism. Most epigenetic processes demonstrate memory and heritability. DNA methylation is an epigenetic process that adds imprints which can be inherited during cell division and across generations. DNA methylation adds an additional level of information to the basic DNA sequence and can influence chromatin organization and the function of the DNA sequence. In bacteria, it works as a defence strategy and preserves genome integrity. DNA methylation in eukaryotes has been implicated in a large number of cellular regulatory processes and is implied in development, differentiation, life style diseases and cancer. Mammals have an intricate DNA methylation machinery with dNMT1, 3A and 3B enzymes. The human X chromosome inactivation, an example of differential regulation of homologous chromosomes, is known to involve many epigenetic processes with intricate interactions of lnc RNAs, miRNAs and DNA methylation. Drosophila possesses very low levels of DNA methylation with only dNMT2 gene. Since Drosophila is an important model organism for study of development and differentiation, the implications of this sparse DNA methylation and the lack of DNA methylation machinery in Drosophila is discussed.


5-methylcytosine and 6-methyladenine DNA methyltransferases chromatin remodelling CpG methylation 



Deepti Deobagkar (nee’ Chhaya Achwal) is an ISRO (Indian Space Research organization) Chair Professor, a former Professor of Molecular Genetics, Zoology Department and former Director, Bioinformatics Centre at Savitribai Phule Pune University. The author would like to acknowledge support from innovation grant and UGC CAS for the work. Help from Shriram Rajpathak, Varada Abhyankar, Saniya Deshmukh and Pawan Mishra is acknowledged. Dileep Deobagkar has provided critical comments which are acknowledged. This article is written as an acknowledgement to Prof. H. Sharat Chandra, my Ph.D. supervisor, who introduced me to the fascinating world of imprinting and DNA methylation. The work on Drosophila DNA methylation and human X chromosome inactivation was initiated with him.


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Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.ISRO Cell and Centre of Advanced Studies, Department of ZoologySavitribai Phule Pune UniversityPuneIndia

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