This is why scientists should focus on Epigenetics

This is why Mendelian laws are not valid anymore

http://www.sciencedirect.com/science/article/pii/S1631069116300646
 
1. "A few years later, the situation became even worse with the discovery of alternative splicing. In alternative splicing, a given ‘split gene’ can code for various different proteins, depending on whether this or that exon is expressed at a given time (for instance a certain exon is expressed in embryos, another one is expressed in the adult organism)."

The most significant EPIGENETIC factors modulating the alternative splicing machinery:
a. microRNAs  b. DNA methylation  c. Histone markers

2. "Other phenomena are also quite challenging for the notion of a gene as ‘no more than a coding sequence’: assembled genes (where germinal sequences, often designated as ‘genes’, are assembled to make a single somatic gene, a situation commonly found in immunogenetics: all antibodies are coded by assembled genes); inversion of the reading frame (meaning that the same DNA sequence can be transcribed in both directions, resulting in different proteins)."

Especially microRNAs (EPIGENETICS) mediate the production of antibodies.

3. "Partial overlapping of the reading frames (the same sequence translated in different frames can give up to two or even three different proteins)."

Transcription of overlapping reading frames is regulated by EPIGENETIC mechanisms:
a. DNA methylation  b. microRNAs  c. Histone markers

4. "Multiple initiation and termination sites of transcription (producing a multiplicity of RNA molecules out of which proteins will eventually be synthesized)."

This is based on EPIGENETIC mechanisms.

5. "Non-universality of the genetic code (e.g., a slightly different code for nuclear genes and cytoplasmic genes: this means that the same sequence, in the same organism, can lead to different proteins)."

Because protein production is mediated by several EPIGENETIC mechanisms.

6. "This is only a partial list. Today, many molecular processes are known that challenge the traditional ‘one gene-one protein’ dogma. In reality, it seems hopeless to provide a general definition of the gene on the basis of exclusively molecular criteria."

7. "The discovery of non-coding RNA has maybe been the most impressive discovery in molecular biology since 2000. Recent data show that 98.5% of our genome is not translated into proteins, but more than 70% is transcribed into RNA (EPIGENETICS). Furthermore, 70,000 promoter regions (EPIGENETICS) (the sites where proteins bind to control gene expression) and 400,000 enhancers (EPIGENETICS) (regulatory sites that affect the expression of distant genes) have been discovered in the human genome. These findings suggest that the information contained in our genome goes far beyond the usual picture of 20,000–25,000 protein-coding genes. (My comment: 19,600) There are many more functional units than those protein-coding genes. Given this situation, one might think that the word ‘gene’ could be abandoned, and replaced by more precise terms."

My comment: The DNA sequences, often designated as 'genes', are very raw material for several epigenetic mechanisms that control cellular processes. All change in organisms is based on epigenetic regulation of existing biological information OR loss of it. That's why there are no mechanisms for evolution. Life is not driven by DNA's gene sequences. Genes are driven by life(style).

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