Inheritance is more than just genes. A new wave of research is unravelling the secrets beyond genes to identify what other biological information parents pass to their offspring, and cells pass on when they divide. It seems that it is not just genes that are inherited from one generation to the next but other factors that particularly affect development and disease (like cancer).

Every human being is made up of billions of tiny cells. These cells are constantly dividing and muliplying to replace dead or damaged cells. Within each cell is a complete set of all the genes that make up the coded instructions for the whole organism. Parents pass on their genetic information and associated traits to the offspring, and cells pass it on as they divide.

Because of their role in determining the functions and traits of a living organism scientists are researching genes in cell organisms to try and find out what they do. This has led to important discoveries including genes linked to breast cancer in humans.

Genes are sections of DNA. DNA looks a bit like a twisted ladder commonly called a double helix. The double helix DNA is packed into a structure called chromatin which forms chromosomes.

Research into what happens in cells has shown something remarkable. It is not just the genes that influence the traits and functions of an organism but also epigenetic or non-gene factors. These epigenetic factors are features within the cell that can be inherited when cells divide but they don't change the genes themselves. However, epigenetic factors can modify the behavior of genes. Epigenetic factors have important roles in regulating human disease.

Understanding epigenetics is fundamental to unravelling the intricacies of how genes and organisms work. Because of its fundamental nature epigenetics has broad potential implications across all the biological sciences.

Epigenetics links the fields of genetics and developmental biology. Epigenetics is the fundamental biological process by which organisms with two or more different cell types establish patterns of differential gene expression (turns on) that are stable through cell division.

Researchers discovered that chromatin, the complex formed by DNA and histones (proteins that bind strongly to DNA, thereby packaging it in chromosomes) regulate gene expression. This additional layer of regulatory instructions, which are not held in DNA, comprise the epigenetic code.

Epigenetic differences explain why two cloned organisms are not the same or why twins develop illnesses of distinct genetic origin. Epigenics not only adds to our understanding of the relations between the environment and genetics but also provides an explanation of the basic aspects of cell biology. Deciphering and understanding the epigenome will shed light on fundamental processes in cell physiology.

This knowledge will improve our understanding of the development of tumors and other diseases, and may lead to the design of new treatments for these conditions. A new family of epigenetic drugs, designed to reverse the changes in the epigenome that occur during the development of several kinds of cancer, is currently available. Several of these pharmacological agents are now being used to treat some types of leukemia and breast cancer.

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