2016/11/17

One genome - Two structures

THE CATERPILLAR AND THE BUTTERFLY
ONE Genome - TWO Structures


http://multivu.prnewswire.com/mnr/mds-foundation/37124/docs/37124-epigenetics_unbranded.pdf

Excerpt: "When the caterpillar changes into a butterfl y, its genome – its basic genetic sequence – does not change. The differences between its two forms result from turning on and off different genes. These changes in GENE EXPRESSION (turning a gene on) and GENE SILENCING (turning a gene off), which do not change the underlying DNA sequence, are collectively referred to as EPIGENETICS. In some cases – the caterpillar and butterfl y, for example – these changes are normal and expected and may be required for development. But diet, environmental effects or even pre-natal factors can create unintended, reversible chemical modifications that mark a gene to be expressed or to be silenced. Some of these epigenetic changes may be benign. But when they allow cells to multiply uncontrollably, the result can be cancer!"

My comment: The genome of butterfly eggs contains all information necessary for every four forms for metamorphosis. This makes us realize that this kind of way to use biological information is not possible to evolve. Perfect timing of those phases is directed by diet induced microRNA regulation.

Metamorphosis is a perfect example of a power of epigenetic control of gene expression. Organisms have silenced genes and activated genes. Genes can be switched on or off rapidly with needs of adaptation. These clever mechanisms point to creation and Intelligent design.