The largest genome ever known, exceeding the human genome by more than 50 times, was found in a little, unassuming plant called Tmesipteris oblanceolata. With 160 billion base pairs, this fern surpasses both the previous record holder, Paris japonica, and the biggest genome, the marbled lungfish, by a substantial margin.
Jaume Pellicer, an evolutionary scientist at the Botanical Institute of Barcelona, co-authored the study. Since he had previously assumed that P. japonica had the maximum genome size, this discovery caught him off guard. This plant, which is indigenous to the archipelago of New Caledonia and the surrounding areas, makes one wonder how one can manage a genome that is so large.
The evolution of such a large genome remains a mystery. Although larger genomes usually need more energy and materials for cell growth, in a calm setting with low competition, this may not be an issue. This may account for the fern’s enormous genome as a result of gradual accumulation.
Although current methods may face challenges in sequencing and assembling such a massive genome, understanding such genomes might shed light on how organisms adapt to their environments and how resilient they are.
