Sex ed just got a little more complicated

It's amazing how the field of stem cell research has advanced so much in such a short amount of time. Today, just a little over a decade after the first stem cell line was produced, scientists announced another breakthrough - turning stem cells into sperm.

In a paper published in the journal Stem Cells And Development (PDF), British scientists from England’s Newcastle University detail a technique for turning stem cells with male chromosomes into reproductive germline cells and prompt them to divide into sperm.

Like non-stem derived sperm, the in vitro versions have 1/2 the amount of genetic material of a regular cell, have a head and a tail, and are capable of swimming and activating an egg for fertilization.

And, interestingly enough, they were only able to produce them with male-derived cells. Female stem cells could begin the process, but stopped at an early stage, suggesting that genes on the Y chromosome are absolutely essential for sperm development.

While this step is a huge one, it's important to note that these sperm are not the same as the normal, mature sperm which are created in the testes, and cannot be used to produce fertilized embryos and offspring. There are other external structural differences which make these man-made sperm unable to act like normal sperm. So while it's an amazing discovery, it isn't a cure for male infertility - yet.

The sperm do, however, give us valuable insights into the origins of sperm and perhaps the underlying causes of infertility. The team is now trying the same trick using skin cells of infertile men and studying the differences between how those sperm and their embryo-derived ones develop, with the hopes of understanding more about the root causes of infertility. These studies may lead to new treatments for infertility, although at the moment, British law forbids the implantation of such sperm into humans, and any lab-grown embryos (if they could get the sperm to successfully fertilize an egg) can only be grown for 14 days, at which point they must be destroyed.

Even if a cure for impotence isn't in the near future, this new technique allows us to speed up nature's clock and see sperm development in a way that we have never been able to before. In the human body, it takes 15 years for the cells which develop into sperm-producing cells to develop and mature before they produce sperm - a process we have never been able to witness step-by-step. Now, it takes only 3 months, granting scientists the unique opportunity to learn even more about human development.


Nayernia, K., Lee, J., Lako, M., Armstrong, L., Herbert, M., Li, M., Engel, W., Elliott, D., Stojkovic, M., Parrington, J., Murdoch, A., Strachan, T., & Zhang, X. (2009). In Vitro Derivation of Human Sperm from Embryonic Stem Cells Stem Cells and Development DOI: 10.1089/scd.2009.0063

Weekly Dose of Cute: Zonkey

OK, everyone. I'm back. I swear. I know, I know - It's been awhile. But we've finally settled in here in Hawaii and are having a blast enjoying the gorgeous weather and new surroundings. Sorry I've neglected you all for so long - I know, I'm a jackass.

No wait, that's these little guys:





OK, to be fair, they're only 1/2 jackasses - they're 1/2 donkey, 1/2 zebra. They're Zonkeys - or zebrasses, zebronkeys, zeasses, zeedonks, zebadonks, zenkeys, donbras, donbris, or deebras... not one of which is a technically correct term for them. The better terms, to those who claim to know such things, are zebrinnies, zebrulas, and zedonks. A zebrinny is the offspring of a male donkey and a female zebra; a zebrula is the offspring of a male zebra and a female donkey; a zedonk is the offspring of any zebra and any donkey - or, just generically, they're all zebroids (crosses between a zebra and some other horse species).

The reasons such crosses are possible is that donkeys (Equus africanus asinus) and zebras (Equus quagga, Equus zebra, or Equus grevyi) are both closely related members of the horse family. Even still, these mixes are rare. But they do occur where the two species are kept in close quarters or when people decide that a cute hybrid sounds like a fun idea. Like mules (crosses between horses and donkeys), they are genetically sterile due to an odd number of chromosomes disrupting meiosis. The trouble is that donkeys have 62 chromosomes while zebras have anywhere between 32 and 46, depending on the species. Somehow, the weird combination allows for viable gestation and development, but not viable sperm or eggs to continue the next generation.

There is one recorded case where a zonkey has successfully bred - at least according to Charles Darwin. In The Origin of Species, he reported a case of a zonkey that mated with a bay mare to produce a horse-zebra-donkey hybrid. Unfortunately, no such successful pairings have been recorded since... It would have been fun to try and name them. Zehordonks? Hordonkbras? Donzeeorses?

Animal Planet's Giving Me A Birthday Gift!

I've thought for a long time that Animal Planet has been dropping the ball on something. You see, they're supposed to be a whole network dedicated to Animals. Large, small, domesticated, wild - all of them. And they generally do a great job of that. They have specials about all kinds of creatures, from the littlest bugs to the largest whales. But they have overlooked one kind of animal, and it's kind of a biggie. Of course, since it's me talking, I'm referring to parasites.

I mean, come on - it's the most popular lifestyle on earth (just ask Carl Zimmer). How can a channel dedicated to animals of all kinds ignore the largest group of animals we have?

They can't - and they aren't. This summer, Animal Planet is premiering a new series called "Monsters Inside Me," a lovely foray into the disgusting, fascinating, and dangerous parasites that live inside people. As they write in their press release for the show:'

Not all monsters are big. In fact, some of the most deadly organisms in the world are invisible to the human eye. Using size to their advantage, microscopic parasites quietly invade their hosts without fear of inhibition or detection. Once inside, these creatures wait in concealment for months, or sometimes years, before striking—all the while, silently feeding off their victims...

“MONSTERS INSIDE ME is part horror movie, part medical detective story,” says Marjorie Kaplan, president and general manager of Animal Planet. “Parasites live everywhere—our water, soil and even in the air we breath. When it comes to these stealth creatures, there’s no where to hide.”

It's as if they heard my unspoken demands and decided to make an entire series to placate my whims - and, just to let me know that it's just for me, they're premiering it next week on July 1^st - MY BIRTHDAY. It's the best birthday gift Animal Planet could have gotten me*!

Monsters Inside Me is hosted by biologist Dan Riskin, who has a PhD from Cornell and currently works at Brown University studying the only mammalian parasite in the world - the Vampire Bat. He, along with medical professionals, probe into real cases of people infected with parasites large and small, from annoying to life-threatening.

Anyhow, mark your calendars for July 1^st at 9 PM EST! I'm also working on getting you some special sneak peaks or behind the scenes info from Animal Planet... so stay tuned!

*besides a nice, face-to-face interview with Dave Salmoni - HINT HINT

New Series "Understanding our Bodies: The Physiology of Nutrition"

Hey there Observations of a Nerd readers,

If you've been here long enough, you might remember me mentioning a side project that I write for called Nutrition Wonderland. Well, it's taken on a life of its own, and it's now a fully-functioning and amazing site on nutrition and health - you should go check it out.

I wanted to tell you guys about my newest endeavor there called "Understanding our Bodies: The Physiology of Nutrition." I'm writing a series about how the way our bodies work relates to what we eat and how we feel. If you like some of the stuff on here, you should really go check it out. Two installments are already up, Leptin, the Fullness Hormone and Serotonin, The Connection Between Food and Mood. They're both chock full of great information about our bodies and the science that went into what we know about them, and there will be more to come in the series.

Anyhow, I figured you might need something to read as I'm busy prepping and moving to Hawaii and have generally failed to be entertaining every day :)

Until Later,
Christie

Don't try this at home...

**giggle** That is one bold monkey - but the music really makes these videos.

Weekly Dose of Cute: Fennec Fox Babies

Yeah, yeah, I've done these little guys before. But come on - just watch the video. I dare you to claim that you are not overwhelmed by the Cute.


HT Zooborns, again. Those guys kick some serious ass when it comes to finding the world's cutest animals

I WANT

So, I kind of have an obsession with small and miniature versions of things. I saw this car in a parking lot yesterday, and I just couldn't help snapping a pic. I WANT THIS CAR.


It's a baby car! Isn't it ADORABLE? Someone should buy me a car like this. Seriously.

Warning: Absolute Genius.

Beaches come with warning signs about hazardous marine life or rough seas. Now, finally, someone is warning the marine life about its biggest threats. They're putting labels on aquarium tanks so that the sharks inside can read the danger that lurks on the other side of the glass:



HT Oceanic Dreams
Absolute genius, Save Our Seas - absolute genius.