2017/01/16

New finding reveals the importance of non-coding RNAs in stem cell fate

Traits are not determined by gene sequences


Excerpt: "MicroRNAs are small, non-coding RNAs that do not translate into proteins, yet have a profound impact on gene expression regulation. He and her colleagues found that a microRNA called miR-34a appears to be a brake preventing both ES and iPS cells from producing extra-embryonic tissues. When this microRNA was genetically removed, both ES and iPS cells were able to expand their developmental decisions to generate embryo cell types as well as placenta and yolk sac linages. In their experiments, about 20 percent of embryonic stem cells lacking the microRNA exhibited expanded fate potential. Furthermore, this effect could be maintained for up to a month in cell culture.

"What is quite amazing is that manipulating just a single microRNA was able to greatly expand cell fate decisions of embryonic stem cells," He said. "This finding not only identifies a new mechanism that regulates totipotent stem cells, but also reveals the importance of non-coding RNAs in stem cell fate."

Additionally, in this study, He's group discovered an unexpected link between miR-34a and a specific class of mouse retrotransposons. Long regarded as "junk DNA," retrotransposons are pieces of ancient foreign DNA (my comment: this is an assumption) that make up a large fraction of the mammalian genome. For decades, biologists assumed that these retrotransposons serve no purpose during normal development, but He's findings suggest they may be closely tied to the decision-making of early embryos."

My comment: Programming of stem cells is done by microRNAs. Every somatic cell in your body has the exact same gene sequences. The DNA in the cells need to be expressed by epigenetic control of gene expression in order to achieve required cell specific differentiation status. This complex programming is made by microRNAs.



MicroRNAs can be found in human sperm for example. They cause epigenetic alterations to be inheritable through several, even hundreds of generations. MicroRNAs are the master regulators of gene expression. Skin, hair and eye color are inherited by microRNAs and other non-coding DNA. That's why genetically identical twins can differ with skin, hair and eye color. That's why this kind of phenomenon is possible:

http://lifestyle.one/closer/family-money/family/baby-ex-boyfriend-genes-family-pregnant/


Excerpt: "But, as it now turns out, scientists have claimed that traces of our EX PARTNER could also appear in our little one’s genetic makeup.

Yup, even if it’s not their baby - weird, huh?

Scientists at the University of South Wales observed an instance of telegony (physical traits of previous sexual partners being passed down to future children) during a study on fruit flies.

Apparently the offspring of the flies matched the size of the first male the mother mated with, rather than its biological father.

“Males contribute DNA to fertilise an egg, but we believe there is something more complex going on.”

It is thought that molecules of the semen produced by the mother’s first sexual partner had been absorbed into her immature eggs."


My comment: MicroRNAs of the semen produced by the mother's ex sexual partners affect the gene expression of the embryonic cells. This points out that gene sequences don't determine traits of the child. Doctrines of population genetics are totally wrong. The evolutionary theory is a dangerous heresy.