Human Egg Farming

We called the ambitious program, ‘Egg Farming,’ over 30 years ago when I worked at Edinburgh University. That goal drew a step closer today as my graduate student from so many years ago published results of growing human eggs in vitro, to a blaze of publicity.

We started by growing mouse and rat eggs in Petri dishes. They were tiny cells nested in follicles that nurse their development, and some reached full size in a week and even ovulated a fertile egg into the culture medium. Our sole competitor in this new science was in the USA where John Eppig developed a more efficient method, and he called the first pup conceived from an egg grown in vitro, ‘Egbert.’ He was a strange and obese animal, and we worried if egg farming was too risky to apply in veterinary or human medicine, but many healthy mice were born later.

Human egg (oocyte). Courtesy: Lucinda Veeck Gosden

It seemed a huge leap from mouse to clinic. Human eggs grow more slowly in the ovary, and we expected the cultures would take weeks or even months and be risky. Progress was agonizingly slow because human ovarian tissue is rarely available for research, especially at the premenopausal ages required. Instead of relying on rodents, we needed intermediate species to forge better methods, and turned to sheep and cow ovaries. Visits to the local slaughterhouse for discarded tissue from butchered carcasses were some of the most unpleasant experiences ever, and almost turned me vegetarian from hearing the crack of the bolt-gun followed by a heavy slump. But they helped us to gain new knowledge when human tissue was unavailable.

A view of Edinburgh and its castle

Professor Telfer’s team in Edinburgh has succeeded with human eggs through careful work with clinical colleagues who asked consent from women to donate tiny slivers of ovarian tissue during C-section. The biopsy doesn’t harm them.

They watched eggs growing in dishes from the earliest stages to full size when a nuclear division occurred and signaled they were ready for fertilization. It is puzzling why the growth is much faster in vitro than in the body, though it is welcome if the eggs are no less competent for making babies. They look normal, but we know from experience how deceptive appearances can be. The only sure test is to fertilize eggs to see if they create healthy embryos, and that will require a special license under UK law.

Why is farming eggs worth the trouble and long struggle?

Progress will continue at a dawdling pace because a mature egg is the rarest cell in the body. For every egg ovulated each month, a man makes 3 billion sperm cells which offer researchers enough material for galloping discoveries in testes. Animals that fertilize eggs outside the body, like frogs and most other species, release as many eggs as they can make because the cost to them is small while superovulation maximizes the chance of making babies. But ovulation in mammals with internal fertilization and pregnancy is restrained by the limited accommodation of the uterus. Nature has arranged a bottle-neck in the egg production line to ensure that few eggs, or only one or at most two in humans, ripen at a time. The rest are consigned to the trash, which egg farming aims to rescue.

If more eggs can be ripened in vitro there will be benefits for animal breeding technology and young patients will have a better chance of preserving their fertility after freezing ovarian tissue during sterilizing treatment for cancer and other diseases. Egg farming will work better for child patients with their larger stores of eggs than in adults. Nearly a quarter-century ago, our first patient at an infant age had ovarian tissue stored while she was treated for Wilm’s tumor. The news from Edinburgh today was welcome for her and others with investments in the frozen ovary bank.

Next Post: Snowy tracks

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From Faith to Hope in 2018

I don’t have much faith in my New Year Resolutions, but there is a four-letter word I will try to keep muttering as world news unfolds in 2018. No, I don’t mean that word!

When Galadriel expressed the state of world affairs in an elvish way, I think it was a good summary of general feelings today. “The world is changed. I feel it in the water. I feel it in the earth. I smell it in the air. Much that once was, is lost … ” (from The Fellowship of the Ring).

Devonshire tree sustained for centuries

The New Year is supposed to be a time of cheerful anticipation of good things ahead, but there is a widespread mood of pessimism and foreboding after several decades of relatively stable world order, even talk of apocalypse by the end of the century. People who lived through the 1340s and 1940s might understand because they feared the world they knew was coming to an end. The modern challenges are not, or at least not yet, the pandemic disease and political tyranny they faced, but we hear questions whether liberal democracy and other fond institutions can survive the threats of climate change and food insecurity, ecology and extinction, mass migration and nuclear arms. The booming stock market cannot be a salve for an Anxious Age struggling to balance sustainable living with social justice.

Faith is a trust in promises made. We grew up with expectations that lives will continue to prosper in almost every way, and should look back gratefully on more optimistic times. But I wonder if ‘faith’ should now be replaced with the more tentative word, ‘hope,’ which has a more fragile meaning. Hope is a brave outreach for something good that is presently unseen, maybe unknowable, but seems irrational and even foolish to cling to. But I find encouragement in those four letters from stories in history and wisdom literature, like the ones started with the Oriental prince who left the court to become the ‘enlightened one,’ the baby abandoned in the rushes, the other baby born in a manger, and a hobbit who left an obscure shire for a long journey. Those are stories that teach us something can come from nothing, and hope is the comforting watchword that it will be future good. I wish that for myself and for all at this season.

Next Post: Heat in the Dead Woods

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A Biologist in Paradise – new book

I raced to finish this book of 40 essays and memoirs before Christmas. A BIOLOGIST IN PARADISE is as much literary as scientific. It is not a science books for scientists, nor a nature book for naturalists, but I hope both parties will read it.

It is FREE to download until Sunday December 17, 2017, when Amazon forces it back to $2.99, the lowest price allowed for a book of this size (80,000 words). Click the link to the Amazon page or type my name in Amazon Books for countries outside North America.

https://www.amazon.com/dp/B0786X82MX/ref=sr_1_1?s=books&ie=UTF8&qid=1513107905&sr=1-1&keywords=Roger+Gosden

Profit from books I publish at Jamestowne Bookworks goes to a local literacy charity. A print book will follow. After so much effort I hope for more readers but it is hard for authors to get much attention when so many books are published. The greatest thing a satisfied reader can do for an author is to spread the word by writing a review on the Amazon page (a line and appropriate star rating will do), and/ or recommending the book to friends and spread on your social media.

Thanks

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Fall Colors in Appalachia

Most people in this region look forward to the fall more than any other season, despite this being the prologue to winter. Starting in September at the atlas or far end of Appalachia, color changes ripple down the spine to the coccyx at the southern extremity a month later, but the finest sights are in the north and at high elevations. Colorful sugar maples like it cool.

Fall colors in Appalachia

People have probably marveled at the spectacle ever since they first set eyes on it eons ago, and long before they wrote about it. I find it perfectly understandable if Native Americans believed fall beauty was the deliberate artistry of a Great Spirit who painted the trees, flowers and creatures for human pleasure, like the Huron story of a great bear’s blood dripping on the forest from heaven and other stories passed down in tradition and lore. More than anyone else, Charles Darwin deposed humans from the center and purpose of creation, but accommodated his feelings for natural beauty in an evolutionary perspective (‘There is grandeur in this view of life …’), which is surely true though we have paid a price by losing a naïve and supremely arresting joy out of mystery.

When the first people saw the Appalachian Mountains there were no trees because the land had been scraped by glaciers and it took centuries for forestland to replace retreating plants that were the first colonizers after the last Ice Age. We are lucky to live in an era when conditions favor trees with fall splendor, though probably one of the last generations to witness them as climate warming pushes back the season and trees struggle with summer heat. The change is not so much a loss to the tourist industry as to the human spirit.

This year’s weather has muted fall colors in Central Appalachia. The maples were almost denuded a month ago, although the oaks are still green and beeches golden-yellow.

Leaf color chemistry is molded by weather. For the most brilliant display, summers should have plenty of rain because drought triggers leaf abscission. Then, late summer should have warm, dry days and cool nights with little wind. Those conditions prevailed this year, save one—the nights stayed mild. We had our first frost on October 17, but it was slight and night temperatures were mostly above average. An Indian summer spoiled a painted fall.

The closer you look at leaf chemistry the more complicated it seems. This is surely a principle in science as, for example, whether physicists study elementary particles or the cosmos the closer their examination the deeper and further they are borne. Science mines nature, but we never get to the end of the seam. We celebrate this richness, but it must be frustrating for politicians who commission research because they hope complexity will turn into neat answers, yet at the end of a study the conclusions are often provisional and there are plenty of new questions.

Once upon a time, fall colors were regarded as consequences of healthy biochemistry yielding to organic decay. The fact of the matter is half opposite because they involve a rather active process. Some genes switch off while others turn on. Each leaf is more in command of its fate than left to the consideration of entropy. Of course, photosynthesis does shut down in the absence of enough sunshine or moisture, and, to add complexity, deciduous leaves are more responsive than evergreens. It’s a familiar story because a sun-loving pot plant left in a shady place when we go on vacation will be a pile of dry leaves and bare stems when we return. It is a protective mechanism for plants and deciduous trees in autumn to withdraw vital nutrients and minerals from leaves into their ‘body’ for storage until needed at the start of the new growing season when the sun breaks out.

When the green pigment disappears, the yellows and oranges that were present all along are revealed. Beech leaves go a step further when the pigments turn into brown tannins that we notice dangling on stems all winter. But the red and purple pigments of maples and gums are synthesized de novo shortly before their leaves fall.

These are anthocyanins, which are molecules that are abundant in ripe berries and grapes and lend red wine its virtuous reputation. They are beneficial for leaves too where they serve as sunscreens and antioxidants to protect valuable molecules synthesized in the summer from solar rays shortly before the fall. There is another theory that bright colors warn away pests, as if rouge leaves can tell insects they ought to buzz off to find a less vigorous tree. It doesn’t square with the widespread lack of receptors needed for seeing red.

Despite its brisk pace, I believe science will never end and its ambition will never find a final goal. That’s worth celebrating. Life would be boring, almost pointless, if everything was predictable and nothing was mysterious. Mystery is sacred.

Fortunately, there are still countless enigmas in nature to stimulate our curiosity, and keep scientists employed. In this post I can mention only one, though it is relevant here. I wonder why evolution hasn’t given all deciduous trees the same glorious reds and purples in the fall if those pigments are so beneficial. Isn’t natural selection supposed to steer genetics to an optimum fit for the environment? Europeans must be satisfied with their yellow fall leaves and no native reds at this season compared with the hot colors we enjoy most years in eastern North America and Asia. Are there any bright theories out there?

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Jean Purdy_Remembering a Pioneer

Some of the most absorbing stories I ever read were from historians and biographers when they bring to light the lives of forgotten pioneers and heroes. On the rare occasions my writing and research can cast a light on a past life I feel moved by the discovery and heavy with responsibility. I imagine archeologists feel likewise when excavating a pile of old bones in some forgotten tomb if they unexpectedly uncover real treasure— buried evidence to name the bones and flesh them with a notable life story.

These thoughts stirred when I walked the dogs on Jamestown Island. I stopped to chat with a group of archeologists working on the burial site of the first African American woman brought to North America. “Angela” died around 1625, but their work is making her better known than she ever was in her lifetime.

Margot Lee Shetterly has been excavating recent history for her book Hidden Figures, which is now a Hollywood movie. She tells the story of African-American women mathematicians who made major contributions to the NASA space program, although, sadly, only one of the trio lived to enjoy the belated public acclaim.

Young Jean

Stories like these have encouraged me to try to give people I admire the dash of immortality that a story in print offers.  I wrote a short biography of an Englishwoman called Jean Purdy in last month’s issue of the journal Human Fertility. She died at the age of 39 in 1985, but never lived to see how the struggles of her tiny research team have blossomed from a breakthrough to a medical revolution that is creating millions of families with IVF babies. The article is free online here.

 

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