World’s largest genome in slow-growing plant

LONDON - An unremarkable and a slow-growing plant has left the scientists stunned with the sheer size of its genome, which is 50 times bigger than that of our species.

It is an unprepossessing, fragile plant, and a flowering herb that frustrates gardeners for being notoriously difficult to grow.

The DNA in Paris japonica dwarves all other plant and animal genomes that have been analysed so far, reports the Botanical Journal of the Linnean Society.

It is much longer than the human genome, even though our species is thought to be one of the most complex and advanced on the planet, according to the Telegraph.

A genome, the biological code that directs how every organism develops, is made up of the DNA found inside almost all living cells.

The slow-growing plant, native to the Japanese island of Honshu, also found in gardens in Britain, boasts more than 150 billion base pairs - the basic building block that links together to form DNA - in its genome. Humans have just three billion base pairs.

If stretched out, the genetic information contained within just one cell of Paris japonica would stretch more than 328 feet - taller than Big Ben clock tower in London’s Parliament House - while the genome from a human cell would stretch just 6.5 feet.

The discovery has added to questions about why human genome is comparatively so small. It may also lead to the discovery of new types of drugs.

Ilia Leitch, geneticist at Kew Gardens’ Jodrell Lab in the UK, who was part of the research team, said: “When we started looking at the plant on our machine to measure genome size, it was clear there was something odd about Paris japonica.”

“When we worked out just how big it was, I was staggered. I had to make several attempts to be sure. It is amazing how the cells pack all the DNA in there.”