In the video above, you're seeing heart cells created from skin cells. Stanford's Ricardo Dolmetsch, PhD, and his colleagues performed the conversion using iPS-cell technology, in which cells can be reprogrammed in a petri dish into embryonic-stem-cell-like induced pluripotent stem (iPS) cells. Like embryonic stem cells, iPS cells have the capability to survive, thrive and divide in a dish as well as to differentiate, with the help of sundry chemical nudges, into specific cell types: heart, brain, pancreas, you name it.
In this case, Dolmetsch's group steered their skin cells back to iPS status and then forward to cardiomyocyte (heart cell) status. These cardiomyocytes spontaneously formed little, beating heart-like clusters in the dish - amazing in itself, although not the first time this feat has been performed.
But note that the "nano-heart" in the top dish beats at about the rate a normal, healthy heart at rest should: about 60 times a minute. The counterpart heart in the dish just above this paragraph, however, is barely achieving a 30-beat-per-minute rate. While the first "nano-heart" was made from skin cells of normal subjects, the second one was generated from young patients with Timothy syndrome. This disease's symptoms include severe heart arrhythmia that, all too often, leads to lethal fibrillation - heart cells contract willy-nilly and the heart's pumping action fails.
Because Timothy syndrome patients' skin cells carry the same genetic defect as their heart cells do, cardiomyocytes created from those skin cells can be studied noninvasively. Dolmetsch and his associates even used these "disease in a dish" cells to screen, with initial success, for drugs that might have the ability to reverse the arrhythmia in the defective cells.
The new method is a great way to explore genetic disease in otherwise inaccessible organs. With Valentine's Day almost upon us, it's a timely gift to the ticker-tinkering trade.