Why a mother's baby might look like her EX? Embryonic development is regulated by RNA molecules

Epigenetic information layers are established by macromolecules - Embryo-uterine crosstalk guided by RNA molecules from extracellular vesicles


Excerpts: "Once considered a simple medium for sperm and embryo transport, the functional spectrum of uterine fluid is now expanding. Novel molecular players, such as extracellular vesicles and mobile RNAs, have been detected in the uterine fluid of livestock, rodents, and humans. These novel molecules, together with previously known ions and proteins, ensure uterine fluid homeostasis and facilitate embryo–maternal interactions. Here, we propose that these molecules may also carry information that mirrors maternal environmental exposure and possibly relay such information to the embryo via uterine fluid, generating long-term epigenetic effects on the offspring via embryonic and placental programming.

...Extracellular vesicles (EVs) that carry a variety of macromolecules (e.g., proteins or RNAs) have been detected in the uterine fluid of mammalian species, including humans, and have the potential to mediate embryo–uterine interactions.

Functional noncoding (nc)RNAs encapsulated within and floating outside EVs can be transferred into floating blastocysts, suggesting a putative function in the genetic and/or epigenetic regulation of embryonic features, which might modulate embryonic and placental development.

Maternal exposures or eating habits have been reported to change the intrauterine (uterine fluid) environment, which might influence embryo quality and epigenetic regulation of gene expression. This mechanism might help explain the observed epigenetic inheritance of maternally acquired traits, as in the case of metabolic disorders.

Before and during embryo implantation, uterine fluid is the liquid medium that connects the floating embryo(s) and the uterus, and has the potential to transfer vital information between the embryo and the uterus. Indeed, recent studies are shedding light on new forms of embryo–maternal communication via the delivery and/or exchange of extracellular vesicles (EVs) and mobile RNAs, newly identified information carriers that exist in the uterine fluid.

Among the various cargos of EVs, ncRNAs are of particular interest given their well-known functions in genetic and epigenetic regulation. Studies of circulating EVs (exosomes) have revealed that they contain different types of ncRNAs, including miRNAs, tRNA-derived small RNAs (tsRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs).

...Over the past several years, growing evidence has robustly demonstrated that the epigenetic information carried in parental gametes can transfer acquired information to offspring.

The impact on the ICM might affect the trajectory of fetal development and may cause disease predispositions in the offspring via a butterfly effect, in which the initial small bias (for example, in essential gene expression) is amplified throughout development and causes long-lasting effects in the offspring. This might occur via transcriptional changes or be regulated via epigenetic changes, such as DNA methylation or various histone modifications, as shown in recent mouse studies."

My comment: After fertilization nearly all epigenetic markers are wiped out of the embryo which means there are only stem cells left that lack all information required for cellular differentiation and specialization. This means that individual traits have also been erased. They are established by maternal macromolecules carried by maternal EVs. From father's side, there are thousands of different RNA molecules in the sperm that stay inside the mother and affect embryonic development. This is how inheritance of traits functions.

The following might be a shocking news:

Excerpt: "This has very important ramifications for women. Every male you absorb spermatazoa from becomes a living part of you for life. The women autopsied in this study were elderly. Some had been carrying the living male DNA inside them for well over 50 years.

Sperm is alive. It is living cells. When it is injected into you it swims and swims until it crashes headlong into a wall, and then it attaches and burrows into your flesh. If it’s in your mouth it swims and climbs into your nasal passages, inner ear, and behind your eyes. Then it digs in. It enters your blood stream and collects in your brain and spine.

Like something out of a scifi movie, it becomes a part of you and you can’t get rid of it.

We are only now beginning to understand the full power and ramifications of sexual intercourse."

My comment: This is why a mother's baby might look like her ex. And this is exactly what the Bible tells about this:

Matthew 19:5 "And said, For this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh?"