Of Molars and Marraige

When I miscarried some years ago, I frantically searched for answers to my diagnosis: partial molar pregnancy.   I came across a fascinating study written about the characteristics of egg and sperm sex chromosomes.  You can find the complete article here.

Although the article's conclusion leans towards the complications of cloning and imprinting a human being, it is the differences between maternal and paternal chromosomes, as seen in the development or termination of an embryo, that intrigues me.

For any baby to grow and develop normally, there needs to be a set of maternal chromosomes (23 autosomal plus one X chromosome from the mother's egg) and a set of paternal chromosomes (23 autosomal plus an X or Y chromosome from the father's sperm).

And the two sets of chromosomes must come from both parents: one paternal and one maternal.

This is due to something called imprinting which allows or inhibits certain genes to "turn on" or "stay off" depending on its parental or maternal source.  Even if the embryo were to have its full two sets of chromosomes, but had obtained both from a maternal source or both from a paternal source it would fail to reach a stage of viability.  Variations outside of the traditional maternal/paternal pairing causes the development of the embryo impossible, as in the case of a partial or full molar pregnancy.

"The biological logic behind imprinting is far from clear.  One appealing theory is that it reflects a conflict between the goals of the mother's and father's genes: the genomes have different agendas and are, in fact, 'at war' - the battlefield being the fetus growing within the mother.

"The idea is that the genes from the father are trying to drive the fetus to be big and strong by extracting as many nutrients as possible from the mother - for example by maximising the size of the placenta.  Meanwhile the maternal genome is defensive, taking care of the fetus developing now but safeguarding the mother to produce and feed further offspring.  The characteristics of the hydatidiform mole - a massively proliferating placenta - are consistent with two sets of paternal genes furiously driving development without the balance of the maternal genome."

(That last example is what I had, except I also had a separate viable, yet malformed, fetus that eventually died.  Both the mole (cancerous placenta) and the fetus were naturally aborted and I miscarried at around 10 weeks.) 

In contrast, when two sets of maternal chromosomes come together, the zygote becomes a benign tumor, grows, but no placenta develops.  It is eventually and naturally aborted.

Isn't that interesting?  I think it's awesome.

The author says "at war", but they're not at war at all.  The maternal and paternal sets of chromosomes are keeping balance - a perfect balance of progressing one life while preserving the other.  Together they do not take more than can be given; they do not cease to exist for fear of taking what is being offered.  They combine, create, and cooperate to become something perfect - a living soul, a baby, one.

And do you know what comes to mind?  Marriage.  Marriage not in the sense that the man takes 'til he kills and the woman gives 'til she dies, but marriage in which it takes two - a man and a woman - to create the perfect balance that will progress to become something perfect into the eternities.  Awesome.