Armed with innovative genetic tools and techniques, conservation biologists and veterinarians in India are banking away genetic resources of wild animal species, especially those that are at risk of being extinct in the near future.
Often likened to a 21st century Noah’s Ark, such genetic repositories are the animal equivalent of a national seedbank for conserving plant genetic resources.
The National Wildlife Genetic Resource Bank, a state-of-the-art facility housed at the Laboratory for the Conservation of Endangered Species or LaCONES, Hyderabad, has embarked on the long-term storage of tissues, primary cells, sperm, eggs, embryos and genetic material (DNA/RNA) of as many wild animal species as possible for both research and conservation breeding.
The idea is to bolster research and application of genetic and reproductive technologies for species conservation, said B Sambasiva Rao, senior scientist at LaCONES.
LaCONES is a unit under the Centre for Cellular and Molecular Biology, located at Hyderabad in Telangana.
“The more genetic diversity we have, the better the chances for population sustainability,” Rao told Mongabay-India.“The NWGRB [National Wildlife Genetic Resource Bank] is the first of its kind in India. So far we have collected and preserved genetic resources from 23 species of Indian species. We have a capacity of 17,000 vials which can be extended further. The idea is to collaborate with zoos across the country to collect genetic material.”
So far Nehru Zoological Park, Hyderabad, is working with the lab to safely deposit sperm and eggs of dead animals of various species. Partnership with more zoos is on the cards.
It would also facilitate exchange of genetic material between Indian zoos for maintaining genetic diversity and aid in enhancing accessibility to scientists and wildlife managers for implementing conservation programs.
Storing genetic material and cells
This state-of-the art biobank uses extremely cold temperatures to cryopreserve tissues, primary cells (precursor cells for cloning), semen and eggs and freeze DNA/RNA and blood samples in special tubes. ‘Cryopreservation’ is the use of very low temperatures to preserve structurally intact living cells and tissues.
Liquid nitrogen – an extremely cold liquid that can burn your mouth – is used to cryopreserve semen and eggs at temperatures of -196 degree Celsius. Freezers at -30 degree Celsius and -80 degree Celsius have been put in place to safeguard blood and DNA samples.
Rao and colleagues believe that this irreplaceable stock of gametes, primary cells and tissues collected opportunistically from threatened species could be an important step in establishing genetic resource for reproductive technologies in conservation breeding and species management programs.
“The biorepository can be used for regeneration of wild animals [using techniques like] cloning and for genetic studies,” Rao noted. “Assisted Reproductive Techniques ( such as artificial insemination and in-vitro fertilisation are being deployed to produce offsprings from germplasms such as eggs and semen.”
He explained that cryopreserved semen can be used to inseminate suitable females of the same species. It can also be used to produce embryos by in vitro fertilisation. These embryos are then transferred to suitable females.
Similarly oocytes can be used to produce embryos through IVF whenever the semen of the same species is available.
“Primary cells can be used as nuclear donors to produce cloned embryos by somatic cell nuclear transfer. These embryos are finally transferred to suitable females of the same or closely related species of the donor cell,” he said.
Blackbuck, spotted deer and blue rock Nicobar pigeons were successfully reproduced by artificial insemination using fresh semen by LaCONES scientists, said Rao.
Genetic resource bank and allied research not only aids efforts to save the last remaining numbers of a species but also enables scientists to understand their evolution and population dynamics.
A worldwide network of Noah’s arks
The Hyderabad facility is among a clutch of projects worldwide on a mission to collect, preserve and harness the potential of gametes, tissues and DNA samples from endangered animals. Some of these facilities are the San Diego Zoo Institute for Conservation Research (“Frozen Zoo”), the UK’s Frozen Ark Project and the Ark of Life in Israel.
Whole genome sequencing projects for African elephants, two-toed sloths, and gorillas have all benefited from the Frozen Zoo.
Timing is a crucial factor in maintaining these stocks.
“The delay between the death of the animal and excision of tissues (ovaries, testicles and other tissues) from the dead animals – this time is very crucial to maintain the integrity and viability of the cells in tissues. The procedure for cryopreservation of semen and oocytes are not same for all wild animal species. It needs to be optimised accordingly,” Rao said.
Meanwhile, the DNA bank at the Centre for Wildlife Conservation Management and Disease Surveillance at Indian Veterinary Research Institute in Uttar Pradesh extracts and archives DNA from animal specimens (such as bone, blood, hair) it receives from north India for disease diagnosis and forensics.
“Whenever we get samples we extract the DNA and store it. So at a later stage in case of a disease outbreak we can retrospectively examine the preserved DNA of the particular species and check if any mutation was earlier present or not,” said Anil Kumar Sharma, who is in charge of the Centre.
The Centre currently has 250 DNA samples spanning 35 species.
Indian Veterinary Research Institute acts as a national referral centre for veterinary type cultures, disease diagnosis, biologicals and immuno-diagnostics.
“We are trying to add as much as possible to our collection that caters specifically to north India. Gene banks are an important arsenal in future biodiversity conservation challenges,” Sharma added.
Further, in another endeavour at stocking genetic resource, the Zoological Survey of India, India’s premier institute on faunal research, has been steadily building a DNA reference library.
It has contributed 2000 DNA barcodes to global networks such as GenBank and Barcode of Life Data System , according to Vikas Kumar of the Survey’s Molecular Systematics Division.
These barcodes are of species falling in different groups like economically important insects, indicator species of Lepidoptera, freshwater fish and reptiles.
This article first appeared on Mongabay.
