According to a recent report, the South American lungfish (Lepidosiren paradoxa) has the largest genome – all the genetic information of an organism – of any animal on the earth.
Key points
- Scientists have sequenced its genome, finding it to be about 30-times the size of the human genetic blueprint.
- The metric for genome size was the number of base pairs, the fundamental units of DNA, in an organism’s cellular nuclei. If stretched out like from a ball of yarn, the length of the DNA in each cell of this lungfish would extend almost 60 metres.
- The human genome would extend a mere 2 metres.
- Until now, the largest-known animal genome was that of another lungfish, the Australian lungfish (Neoceratodus forsteri). The South American lungfish’s genome was more than twice as big.
- The world’s four other lungfish species live in Africa, also with large genomes. This freshwater lungfish is an extraordinary creature – in some sense, a living fossil.
- The South American lungfish species is found in slow-moving and stagnant waters in Brazil, Argentina, Peru, Colombia, Venezuela, French Guiana and Paraguay.
- It is the nearest living relative to the first land vertebrates and closely resembles its primordial ancestors dating back more than 400 million years.
Largest genome
- There are plants whose genome is larger. The current record holder is a fork fern species, called Tmesipteris oblanceolata, in the French overseas territory of New Caledonia in the Pacific. Its genome is more than 50 times the human genome’s size.
- Tmesipteris oblanceolata contains a whopping 160 billion base pairs.
