The researches find that the An epigenetic change, a form of DNA control, that deactivates some genes linked to cancer late in human development has been conserved for more than 400 million years, new research led by the Garvan Institute of Medical Research suggests. A gene is the basic unit of heredity in a living organism. All living things depend on genes. Genes hold the information to build and maintain their cells and pass genetic traits to offspring.
An epigenetic change
A modern working definition of a gene is “a locatable region of genomic sequence; corresponding to a unit of inheritance, which is associate with regulatory regions, transcrib regions; and or other functional sequence regions “. In common usage, the term gene often refers to what is know more accurately as an allele.
The notion of a gene has evolved with the science of genetics; which began when Gregor Mendel notice that biological variations are inherit from parent organisms as specific; discrete traits. The biological entity responsible for defining traits is term a gene; but the biological basis for inheritance remain unknow until DNA is identify as the genetic material in the 1940s.
Noticed that biological variations
All organisms have many genes corresponding to many different biological traits, some of which are immediately visible, such as eye color or number of limbs, and some of which are not, such as blood type or increased risk for specific diseases; or the thousands of basic biochemical processes that comprise life. Researchers uncover that genes turn on in some cancers in humans also exist in zebrafish but are ‘silence’ within just hours of fertilisation.
The study sheds new light on how our epigenetics can regulate genes; some of which are link to cancer development later in life; over large evolutionary distances. It also uncovers significant differences between how the epigenome ‘resets itself’ in zebrafish and human embryos; which may guide future studies on epigenetic inheritance.
Over large evolutionary
At first glance, humans and zebrafish (a tiny species of fish native to South Asia) hardly seem related in fact, our common evolutionary ancestor dates back more than 400 million years. But genetically, zebrafish and humans are not so different we share around 70% of protein-producing genes. The Garvan-led team set out to investigate how conserve the epigenetic changes, that control how DNA is ‘read’, are during the development of an embryo.
Genes are in part control by methylation tags on DNA that ‘block’ genes from being reading. The researchers first isolate primordial germ cells, the precursor cells of sperm and egg, from developing zebrafish embryos and generate whole genome bisulfite sequencing (WGBS) data a snapshot of all the DNA methylation in the cell.