World’s Largest Genome

Context: Tmesipteris oblanceolate, a fork fern species from New Caledonia, boasts the world’s largest genome.

About:

o It is a small plant (10-15 cm in height), and its leaf-like structures are not leaves but flattened stems.
o Its genome size is 7% larger than the Japanese flowering plant Paris japonica (the previous record-holder), about 25% larger than Africa’s marbled lungfish (the biggest-known animal genome) and 50 times the size of the human genome.
o Its genome is larger than that of a blue whale (the Earth’s largest animal), an African elephant (the largest land animal), and the giant redwood (the tallest plant).
o A genome is the complete set of genetic material (DNA) in an organism.

Importance of Genome

o Instructions for life: The genome contains all the information required for the growth, development, and functioning of an organism.
o Medical applications: It helps in disease diagnosis by identifying genetic mutations and variations. It helps in tailoring personalised medicine and gene therapy.
o Evolutionary biology: Genome analysis helps trace the evolutionary history, relationships between different species and genetic variation within populations to understand adaptation and natural selection.
o Biotechnology: It helps develop genetically modified organisms (GMOs) that improve crop yield, disease resistance, and nutritional value.
o Public health: It helps in conducting epidemiology, which is required for developing effective treatment.
o Epidemiology is the study of the determinants, occurrence, and distribution of health and disease in a defined population.

Reasons a Longer Genome Might Not Be Beneficial

o Higher mutation rates: Longer genomes are more prone to mutations.
o Higher energy and resource demands: Larger genomes require more resources and time for DNA replication, repair, and transcription (a process a cell uses to make the proteins an organism needs to function). This may slow down the organism’s growth and adaptability, making it ecologically restricted.
o Non-coding DNA proportion: A significant portion of many larger genomes consists of non-coding DNA, which does not directly contribute to protein production. Much of non-coding DNA may be non-functional or
“junk” DNA, adding bulk without benefit.

Our Branches