#HematologyTweetstory 10: how did the 5 major #nucleobases get their names? This is slightly tangential to hematology, admittedly, but is a cool story that I’ve been aching to tell since I went through an intense etymology phase many years ago (still have lots of dusty books)./1 
It is hard to imagine just how important seabird guano was economically, back before the beginning of the 20th century when Fritz Haber (who favored #PelgerHuet style eyeglasses😉) figured out how to fix nitrogen artificially & make ammonia. Guano was used for fuel, fertilizer./3
There was even an “Age of Guano” (!) in the 19th century, when the colonial powers snatched up remote little islands around the world... for their guano. One of the reasons the US still claims a bunch of Pacific islands is because of that phase of acquisitiveness in the 1850s. /4
Guano was heavily advertised, too. Because when you see a lovely pastoral image with attractive farmers like this one, the first thing that comes to mind is seabird dung 💩, right? /5
"Guano" is Spanish, but the original word "wanu" was Quechua - the Mayan tongue. It's rare for me to get through clinic or hospital rounds without needing at least one interpreter. (Picture = Brueghel’s Tower of Babel.) The hardest interpreter I ever had to come by: Quechua./6
The next 3 nucleobases were all named by "Ludwig Karl Martin Leonhard Albrecht Kossel" (1853–1927), whose name is reminiscent of massive German compound words. His student Albert Neumann also did key experiments. In addition boasting a fine mustache, Kossel won 1910 Nobel Prize.
#Adenine was first isolated from the pancreas of an ox in 1885 (gland = adeno-, or ἀδήν- in Greek). Not clear why Kossel and Neumann were using the pancreas of an ox for their extractions, other than that it is really big (the same reason it was once used for making insulin.)/8
Then came #thymine, in 1893. Thymine was first extracted from calf thymus, hence the name. BTW the -ine suffix has 2 meanings: “derived from" and "containing nitrogen", both of which apply to the 3 nucleobases thus far./9
Weirdly, the thymus itself is named after thyme (Genus "Thymus"): that wonderful herb that is essential in Mediterranean cooking. Supposedly the name is because the thymus gland resembles thyme leaves. I have to say, this resemblance seems a bit of a stretch to me.../10
Then came cytosine, also first isolated from thymus. Cyto=cell, of course. Low marks for creativity on cytosine! I mean, how many zillions of nitrogenous substances can we say are “derived from cells”? Kossel and Neumann were just mailing it in by this point… #LazyScientist/11
I don't mean to diss cytosine itself, though, which is a particularly cool base because of all the different methylation-related variants including transient species. This image is from WhatIsEpigenetics.com /12
Last, RNA uracil - the only one that doesn’t end in -ine. In 1885, German chemist Robert Behrend (1856-1926) created a bunch of derivatives of “uric” acid (so called because it was first isolated from kidney stones in 1776 by #Scheele); one of them he called "uracil". /13
-il is an unusual suffix; it doesn't have the same specific meaning as a lot of other organic chem suffixes. I'm not sure why Behrend chose that. The journal he published his results in was named after Justus Liebeg – a connection with the guano story above./14
So what prompted this tutorial? The proposal by @NHSuk Health Secretary @MattHancock to sequence all newborns in the UK. Perhaps that is the way of the future, but for now, it is reminscent of the 1997 Ethan Hawke/Jude Law/Uma Thurman dystopian sci-fi film GATTACA. /15
This is the penultimate #HematologyTweetstory for 2019. I'm busy working on an @ASHClinicalNews essay about dystopian 2020 and am planning ~Dec. 25 "A Howell-Jolly Christmas" (w/ apologies to Burl Ives and his #HollyJollyChristmas 🎄🎶🎵 For those attending: enjoy #ASH19 !/16End
