Snuppy is a real clone!

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Remember Snuppy, the cloned puppy? He’s been living under a cloud for a while now, since one of his creators was Woo-Suk Hwang, the Korean scientist who was found to have faked data and exploited his workers, and there was concern that perhaps the dog cloning experiment was also tainted.

Put those fears to rest. Two groups of researchers have independently analyzed Snuppy and its putative clone parent, and both agree that it is most likely a clone. The nuclear markers between the two were identical, while mitochondrial markers were different—exactly what you’d expect in this kind of clone, and not what you’d see from simple twins, for instance, or if someone had faked the samples.


Parker HG, Kruglyak L, Ostrander EA (2006) DNA analysis of a putative dog clone. Nature 440:E1-E2.

Seoul National University Investigation Committee, Lee JB, Park C (2006) Verification that Snuppy is a clone. Nature 440:E2-E3.

PZ Myers’ Own Original, Cosmic, and Eccentric Analogy for How the Genome Works -OR- High Geekology

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I’m teaching my developmental biology course this afternoon, and I have a slightly peculiar approach to the teaching the subject. One of the difficulties with introducing undergraduates to an immense and complicated topic like development is that there is a continual war between making sure they’re introduced to the all-important details, and stepping back and giving them the big picture of the process. I do this explicitly by dividing my week; Mondays are lecture days where I stand up and talk about Molecule X interacting with Molecule Y in Tissue Z, and we go over textbook stuff. I’m probably going too fast, but I want students to come out of the class having at least heard of Sonic Hedgehog and β-catenin and fasciclins and induction and cis regulatory elements and so forth.

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Life will find a way

Creationists sometimes try to argue that what we consider straightforward, well-demonstrated cytological and genetic events don’t and can’t occur: that you can’t get chromosome rearrangements, or that variations in chromosome number and organization are obstacles to evolution, making discussions of synteny, or the rearrangement of chromosomal material in evolution, an impossibility. These are absurd conclusions, of course—we see evidence of chromosomal variation in people all the time.

For example, A friend sent along (yes, Virginia, there is a secret network of evilutionists busily sharing information with one another) a remarkable case study of a radical chromosome arrangement in a mother and daughter. When you see how these chromosomes are scrambled, you’ll wonder how they ever managed to sort themselves out meiotically to produce viable offspring…but life will find a way.

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It’s not just the genes, it’s the links between them

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Once upon a time, I was one of those nerds who hung around Radio Shack and played about with LEDs and resistors and capacitors; I know how to solder and I took my first old 8-bit computer apart and put it back together again with “improvements.” In grad school I was in a neuroscience department, so I know about electrodes and ground wires and FETs and amplifiers and stimulators. Here’s something else I know: those generic components in this picture don’t do much on their own. You can work out the electrical properties of each piece, but a radio or computer or stereo is much, much more than a catalog of components or a parts list.

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Electronics geeks know the really fun stuff starts to happen when you assemble those components into circuits. That’s where the significant work lies and where the actual function of the device is generated—take apart your computer, your PDA, your cell phone, your digital camera and you’ll see similar elements everywhere, and the same familiar components you can find in your Mouser catalog. As miniaturization progresses, of course, more and more of that functionality is hidden away in tiny integrated circuits…but peel away the black plastic of those chips, and you again find resistors and transistors and capacitors all strung together in specific arrangements to generate specific functions.

We’re discovering the same thing about genomes.

The various genome projects have basically produced for us a complete parts list—a catalog of bits in our toolbox. That list is incredibly useful, of course, and represents an essential starting point, but how a genome produces an organism is actually a product of the interactions between genes and gene products and the cytoplasm and environment, and what we need next is an understanding of the circuitry: how Gene X expression is connected to Gene Y expression and what the two together do to Gene Z. Some scientists are suggesting that an understanding of the circuitry of the genome is going to explain some significant evolutionary phenomena, such as the Cambrian explosion and the conservation of core genetic processes.

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Evolution of a polyphenism

Here’s some very cool news: scientists have directly observed the evolution of a complex, polygenic, polyphenic trait by genetic assimilation and accommodation in the laboratory. This is important, because it is simultaneously yet another demonstration of the fact of evolution, and an exploration of mechanisms of evolution—showing that evolution is more sophisticated than changes in the coding sequences of individual genes spreading through a population, but is also a consequence of the accumulation of masked variation, synergistic interactions between different alleles and the environment, and perhaps most importantly, changes in gene regulation.

Unfortunately, it’s also an example of some extremely rarefied terminology that is very precisely used in genetic and developmental labs everywhere, but probably makes most people’s eyes glaze over and wonder what the fuss is all about. I’ll try to give a simple introduction to those peculiar words, and explain why the evolution of a polyphenic pigment pattern in a caterpillar is a fascinating and significant result.

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