10th genome of Christmas: The laboratory mouse

After human, the most studied animal, by a long margin, is mouse. Or, more strictly, the laboratory mouse, which is a rather curious creation of the last 200 years of breeding and science.

Laboratory mice originate mainly from circus mice and pet “fancy” mice kept by wealthy American and European ladies in the 18th century. Many of these mice had their roots in Japan and China, where their ancestors would have been kept by rich households. Unsurprisingly, the selection of which mice to breed over the centuries came down to habituation to humans and coat colour rather than scientific principles.

Continue reading “10th genome of Christmas: The laboratory mouse”

9th genome of Christmas: Medaka and friends

My ninth genome of Christmas is a bit of an indulgence: the gentlemanly, diminutive Medaka fish, or Japanese rice paddy fish.

When Mendel’s laws were rediscovered in the 1900s, many scientists turned to local species they could keep easily to explore this brave, new world of genetics. In America, Thomas Hunt chose the fruit fly. Scientists in Germany explored the guppy and Ginuea pigs. In England, crop plants were the focus of early genetics. In Japan, researchers turned to the tiny Medaka fish, a common addition to many of the ornamental ponds maintained in Japanese gardens.

Continue reading “9th genome of Christmas: Medaka and friends”

5th genome of Christmas: The Fly

The humble fruit fly – Drosophila melanogaster, to be specific – has played a central role in the history of genetics and molecular biology and continues to be important in research.

Championed by the legendary Thomas Morgan at the start of the 20th Century, Drosophila provided a practical foundation for genetics – long before the discovery of DNA as vehicle for passing down heritable information through generations. Morgan and colleagues developed the concepts of ‘gene’ and ‘linkage’, and so we have ‘Morgans’ (and more commonly, centi-Morgans, cM) as the basic units of genetic maps.

Continue reading “5th genome of Christmas: The Fly”