Midwives and Epigenetics

Horizontal “steps” inside spiral ladder of DNA – bases – can be chemically modified, changing how genes work not only in the organism but in its descendants

Call the midwife” is a very popular in Britain BBC drama about nuns and midwives working in 1950s London. Heidi Thomas – screenwriter for the show.

“Radio Times” –  a British weekly TV programme listings magazine – recently published interview with Heidi Thomas in which she says “…epigenetics, which believes our brains are imprinted by the experience of earlier generations…” (p.15). It does not believe that at all.
Epigenetics studies inheritance of changes in  genes not caused by mutations. If you look at the DNA, the bits inside the helix aquires chemical modification (epigenetic changes) or changed to different bits (mutations). A new human is a combination of two parental cells, which transfer DNA with modifications but not anything to do with future human brain function.
We inherit genes, not brain. The genes can be inactivated during an organism’s life and they will work differently in the next generation. For example my mother, exposed in the womb to the low nutrient conditions during the Second World War has developed type II diabetes. This happened likely due to epigenetic modification of her genes, because our family has no history of diabetes.  As I was born in better, fatter 70s, I am not diabetic and there is no way for me to have any memories about the war or any other heritable changes in the brain.
P.S. In case anybody wonders why I don’t regularly update the blog. There is a Russian saying “only a bad private doesn’t dream of becoming a general”.  A I am a good blogger – I am writing an e-book about gene expression.

Book Review: “Like a Virgin”, by Aarathi Prasad

Virgin Mary and Jesus, old Persian miniature. ...

Virgin Mary and Jesus, old Persian miniature. In Islam, they are called Maryam and Isa.  (Photo credit: Wikipedia)

Modern humans about sorted their contraception, but  the reproductive options are still limited to the variations on the  “egg + sperm = baby”.  The amazon review of Aarthy Prasad’s book has promised that it “delivers an astonishing exploration of the mysteries of sex and evolution past, present, and future” and I was mostly interested in the present research summary and  the blue sky options.

Unexpectedly, I liked the historical account of research into reproductive biology.  It’s interesting to realise how women’s role in reproduction was considered   a passive receptacle of male “vital power” –  a whole embryo had been found by some “scientists” curled up in the sperm head.  At the same time inability to conceive or produce a male heir ( the story of Henry VIII and his 6 wives comes to mind) had been repeatedly blamed on women.

The “present” part of the book is full of truly astonishing  facts about human and animal reproduction biology – I was very impressed by hyenas and a woman who accidentally got pregnant while lacking the vagina. ‘Like a Virgin’ contains the best description of three layers of embryo I’ve ever seen and description of epigenetic programming of placenta development is really fascinating.

But as the book approaches the modern pioneering research, the narrative is flagging, disintegrating into  a patchwork description of different labs’ research in progress and other topics loosely connected to human reproduction in XXI century. It jumps from reproductive materials trafficking  to surrogate agencies in Mumbai, to ovaries transplantation, to solo parents – individuals who choose to have and raise children without   a partner. The true virgin birth in mice described on one page – the field of non-canonical reproduction is simply not mature enough to write a book about.

The question I expected to be covered, which  Dr.Prasad doesn’t ask,  is why do we want to have  a virgin birth?  The explanation proposed is that solo parents will ultimately want  the sole (pun intended) source of genetic material. May be I am not narcissistic enough, but I wouldn’t want to produce a second generation  copy of myself, either through cloning or a virgin birth – one of  the joys of the sexual reproduction is the lottery of similar and new features of the child.

So if you are interested in a collection of amusing facts about reproductive biology,   I recommend you to read the book, but if you interested in the state of art in the field of reproductive biology – try Nature reviews instead. And sorry but I can;’ recommend anything comprehensible about the ethics of human reproduction.