THIN;; YOU DIDN’T KNOW
BY KIRSTEN WEIR
1. Sorry, Jimmy: James Watson and Francis Crick did
not discover ;;;. ;at honor goes to Swiss biochemist
Friedrich Miescher, who in ;;;; found the molecule in
the nuclei of white blood cells and called it nuclein.
2. Nor did they ;gure out that ;;; is our genetic blueprint; bacteriologist Oswald Avery and his colleagues
did that in the early ;;;;s. 3. What Watson and Crick
did do, in ;;;;, was decipher the double-helix structure
of ;;;. ;eir discovery ran as a single-page paper in
Nature. 4. Phosphorus is a key component of ;;;, but
late last year a team of ;;;; scientists announced
they had found a bacterium that could use arsenic
instead. “What else can life do that we haven’t seen
yet?” wondered lead researcher Felisa Wolfe-Simon.
5. Don’t try this at home: If uncoiled, the ;;; in all the
cells in your body would stretch ;; billion miles—from
here to Pluto and back. 6. Most of that ;;; resides not
in the cell nuclei, which control heredity, but in our
mitochondria, the organelles (units within cells) that
generate metabolic energy. 7. Puny humans: Paris
japonica, a ;owering plant native to Japan, has the long-est known genome, nearly ;;; billion base pairs. ;at’s
;; times as long as the human genome. 8. Aside from
bacteria, the smallest genome belongs to the intestinal parasite Encephalitozoon intestinalis, with a tri;ing
;.; billion base pairs. 9. Scientists are working to
create vaccines against ;;;, ;u, and hepatitis C from
snippets of synthetic ;;;; the ;;; tricks the body
into producing harmless viral proteins that train the
immune system to attack real viruses. 10. ;;; vaccines for West Nile virus, melanoma, and hemorrhagic
disease are already available for horses, dogs, and
salmon, respectively. 11. At the Chinese University of
Hong Kong, fetal ;;; was extracted from a pregnant
woman’s blood plasma and tested for Down syndrome.
Prenatal ;;; screening could someday replace amniocentesis. 12. Telomeres, sequences of ;;; at the tips
of chromosomes, get shorter every time a cell divides;
when they get too short, the cell dies. Some scientists
are trying to extend life by extending the telomere.
13. Good news if you’re a mouse: Researchers at
Dana Farber Cancer Institute in Boston engineered
mice with telomerase (an enzyme that adds ;;; to
telomeres) that could be switched on and o;. With
the enzyme activated, the mice grew new brain cells
and lived longer. 14. Bad news if you’re a mouse:
Scientists at Osaka University recently developed
mice that are especially susceptible to ;;; copying errors, seeking to increase the rate of mutations
and see what new traits appear. 15. ;e results so
far include short-legged mice, mice with fewer toes
than normal, and mice that chirp like songbirds.
16. Guess who’s in your ;;;? At least ; percent of the
human genome originated in viruses, whose genetic
code was integrated with ours over roughly ;; million
years of primate evolution. 17. Over the next ;ve
years, the International Barcode of Life Project aims
to establish genetic identi;ers for ;;;,;;; species—
short sections of unique ;;; in the same location on
the genome, a bit like the ;;; on your box of Froot
Loops. 18. Already, forensic specialists can identify
criminals from traces of “touch ;;;” left in ;nger-prints at a crime scene. 19. Next up: food forensics.
British microbiologists sequenced ;;; to identify
the bacteria in a round of Stilton blue. ;ey found
that at least six microbial groups in;uence the ;avor
of the cheese’s “dairy matrix.” 20. And scientists at
the University of Guelph in Ontario showed that ;;;
from the worm (actually an agave butter;y caterpillar)
traditionally placed in bottles of mescal leaches into
the liquor. So now we know: You don’t actually have
to “swallow the worm” to swallow the worm.
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