Baiju Krishnan: Applications of Genetic Techniques in wildlfe mana...

Baiju Krishnan: Applications of Genetic Techniques in wildlfe mana...: APPLICATION OF GENETIC TECHNIQUES IN WILDLIFE MANAGEMENT The use of molecular genetic techniques in conse...

Applications of Genetic Techniques in wildlfe management

APPLICATION OF GENETIC TECHNIQUES IN WILDLIFE MANAGEMENT

                                  The use of molecular genetic techniques in conservation biology and wildlife management has become increasingly important during the last decade.  This is mainly catalyzed by the development of the Polymerase chain Reaction (PCR) which requires only minute amounts of DNA for genetic analysis and the possible sources of DNA can be hair, scale ,feaces, feather, urine, buccal cells, egg shells and even foot prints.  Thus it is no longer necessary to obtain blood or tissue samples to study population genetics in animals.  Analyzing ad comparing , the genetic make up of plants and animals, not only improves assessments made using traditional methods, but also yields information otherwise inaccessible.  Even though molecular techniques are too labour intensive and expensive for regular use, they have been made more widely available in recent years due to retirements in laboratory techniques, improvements in computer power and lower equipment cost.  The major challenge for the developing nations to conduct genetic research is of economical one, while for under developed nations is the non availability of technology.

 Techniques

  

      Deoxy Ribo Nucleic acid(DNA) is the principal constitute of genes, and is found in the cells of living organisms including components of blood, skin , hair, nails etc.  DNA molecules are made up of a linear sequences of compounds called nucleotides, and form a long, continuous strand inside a structure called chromosome.  The unique sequence of the nucleotide in a chromosome determines the hereditary characteristics of an individual from its species, sex and to traits such as eye colour.  Each gene occupies a particular location on the DNA strand  making it possible to compare the same gene in a number of different samples.

    Many genetic techniques involve a process in which short segments of a DNA strand are replicated to produce a sufficient quantity of material for analysis.  These segments can then be examined for differences in size between individuals or for differences in the actual nucleotide sequence of the segments.  In contrast, other techniques cut DNA into segments using enzymes and certain of these segments are radio actively tagged to create a visual pattern on x-ray film.  DNA finger printing is the most popularly known of these techniques.  The finger print of one individual can be compared with other fingerprints to determine if two or more samples originated from the same individuals or to identify close relatives such as parent and sibling.

Applications

    Molecular genetics provides powerful tools for wildlife conservation and can similarly play an important role in wildlife management.  First an understanding of genetic population structure of a particular species may aid in the identification of management units and the development of management strategies.  The practical application would be the ability to determine the geographical sources of individuals during certain time periods or in certain locations.  It is a powerful tool in all demographic surveys as well as experiments .  Habitat fragmentation is a threat to survival of wildlife populations in human dominated landscapes.  Connectivity among populations is distinct fragments may play an important role in population dynamics and resistance.  New genetic techniques are used to assess the connectivity in spatially structured and population of threatened species

 Cloning and Biodiversity conservation: 

                         Nuclear transfer technology, popularly known as cloning , where new      “ true to type” individuals are created in the laboratory from the nuclear DNA of other individuals.  Reproductive cloning or the production of offspring by nuclear transfer is often regarded as having potential for conserving endangered species of wildlife.  Factor that govern the desirability, feasibility and practicality of cloning vary among different class of vertebrates, depend upon the peculiarities of the biological systems, the type of species under threat and even the chances  of obtaining suitable funding since the research is very expensive.  Cloning is one of the several ways of increasing the number of individuals within a population.  When populations of free living species are found to be in decline, conservation biology begins to seek methods of showing or reversing the threatening process, many such threats exists including habitat loss through human activity, hunting or over fishing, effects of pollution on fertility and fecundity, predation by introduced species or indeed poor diet through loss of prey species.  In  a few cases these threats can be allevated but this may require the development of nation and international policies that support the conservation goals.  Reproductive technologies may then provide support the conservation goals.  Reproductive technlogies may the provide support usually by assisting genetic management.  An important common aim of conservation breeding programmes with or without the use of assisted reproduction, is the avoidance of inbreeding depression.

    Nuclear Transfer Technology can play  a significant role in the conservation of species, which are on the edge of extinction.  Now captive breeding techniques are adopted for saving such species . For example the population of Mauritius Kestrel declined to about nine individuals in the early 1970’s , four were reintroduced to the island of Mauritius later, and the population is now estimated as 700-800.  In such cases we can seek the help of nuclear transfer technology.  However the population of the species facing extinction is very less and they possess minimal genetic variation.  it is therefore desirable to avoid further loss of diversity.  A subsequent generation resulting from natural breeding or artificial insemination would contain some, but no all of genetic variability of its parents.  Loss would occur if any of the individuals failed to breed, which is a strong possibility with small populations.  If cloning is guaranteed to be 100% successful, a good strategy might be to clone every individual, then allow the off spring to mature and breed naturally.  The probability of losing genetic diversity would then  be reduced especially if each parent gives rise to more than two identical copies of itself.  Thus an interesting and novel theoretical principle in animal conservation emerges; where individuals are effectively induced to reproduce asexually something similar to some plants there by improving the long term fitness of the species through the retention of genetic diversity.

Concept of Environmental Genomics

           Environmental genomics bridges the gap between genetics, physiology and ecology.   It involves utilization of abroad range of modern molecular techniques such as gene arrays and single nucleotide polymorphins (SNP) screen to monitor variation in gene structure and expression.  It can pinpoint potentially novel interactions between environmental stresses and expression of specific human, animal and plant genes.  Environmental  genomics is the application of the knowledge gained on gene identification, structure and expression to environmental protection and management.  It can demonstrate deleterious effects at molecular level before organisms level effects are shown.

Importance of Environmental Genomics.:

                Genomics build upon and enhance traditional approaches to environmental toxicology determination.  It is a key objective for environmental science for improved understanding, identification and prevention of  environmental problems.  It can provide the next generation tools to help protect and manage the environment.  It would be very critical in examining biotechnology’s potential impact on the environment.

Biotechnology and Tree improvement:

                Tree improvement and forest biotechnology offer related scientific means to increase forest productivity , achieve sustained timber yields and perhaps enhance forest biodiversity and conservation of multiple values.  Tree improvement provides classical approaches to achieve better timber production.  It has achieved sustainable gain through generation of tree selection and breeding .  Tree important seeks to identify and improves several important tree attributes including growth rates, disease and pest resistance, adaptability to climatic changes, tree form and wood fiber quality, straightness and taper

Conclusion

  The practical application of bio techniques has many difficulties.  Current success rates with nuclear transfer in mammals are very low.  More over 20 to 1000 nuclear transfers would need to be performed to achieve one viable off spring.  There are so many issues like legal, moral and technical in conducting genetic researches.  Sophisticated labs doing genetic research are less in number and the coordination is also less.  But the potential of genetic techniques in wildlife conservation and management shall not be ignored.  They can help many species to keep their foot prints on this green earth.

(Published on Santorama Vol XX 2006. Author was a Research Scholar in Bio Inorganic Chemistry at Dept. Of Chemistry, University of Kerala)