National Science Day and Rare Disease Day
Talk at Science & Nature Club, Periyar Nagar Public Library, Feb 28, 2017
Anandhi N. MSc., M.S.
Anandhi N. MSc., M.S.
The Science & Nature Club met at Periyar Nagar Public Library on February 26, 2017 at 5.30pm. This monthly meet of the club celebrated National Science Day (that falls on February 28 of every year) and Rare Disease Day (that falls on the last day of February). Speaker Dr. Duraiswmay Navaneetham PhD demystified green revolution and crop genetic modification and explained how these methods benefit the nation. Guest speaker Mr. Satish Srinivas shared with the audience his personal encounter with a rare disease called Alternating Hemiplegia of Childhood (AHC). The evening concluded with Dr. Navaneetham’s rounding up of what planets, stars and constellations will be visible in March’s night sky. Here is a brief summary of the proceedings of the event.
Green Revolution
The American initiated Green Revolution kicked off in Mexico in 1950s as a means to transform the country’s agricultural productivity to feed its growing population. Green Revolution, led by Nobel laureate Norman Borlaug, used technologies including hybridization to produce high-yielding crop varieties (a result of hybridizing two wheat/rice varieties that have beneficial characteristics or traits), synthetic pesticides and fertilizers along with modern irrigation methods. Following the success of wheat production in Mexico, the Ford Foundation and the Rockefeller Foundation of the USA collaborated to establish the International Rice Research Institute in Philippines in order to experimentally produce high-yielding rice varieties, thereby managing to more than double the annual production of rice. This new variety of rice was a hybrid from Chinese DGWG strain (more grains per stalk, tall but weak stalk) with Indonesian Peta strain (fewer grains per stalk, short strong stalk). The resulting target rice strain (more grains and short, strong stalk) was named IR8 after International Rice Research Institute (the 8 stands for eight crossing or generation of breeding).
To avert an imminent famine in India in the early 1960, the Government of India adopted the Green Revolution technology to develop and deploy high-yielding variety of wheat in the Punjab-Haryana-UP belt and later, rice in the southern belt. Dr. M. S. Swaminathan, considered the ‘Father of Indian Green Revolution’ played a leading role in these events. Besides making India self-sufficient in terms of food grain availability, the nation now is also a strong exporter of these cereals.
Dr. Duraiswamy Navaneetham gave a gist about a rare bone disorder Osteogenesis Imperfecta.
His talk also included other science topics, Green Revolution, Crop Genetic Modification, Raman Effect
to commemorate National Science Day.
Crop Genetic Modification
Cell is the basic unit of life. Each cell has a central nucleus that acts as its core or brain. Inside the nucleus resides the chromatin network, a fine strand composed of DNA or De-oxy Ribonucleic Acid. The DNA is made up of many genes. Genes give characters such as tallness, shortness, paleness, darkness etc to organisms including plants.
Stepping up from the above hybridization model employed by green revolution, where two parent plant varieties (of the same species) were cross-bred purposely to bring out a needed trait in the offspring, genetic modification works at a deeper level - where the gene governing a required trait from an organism is deliberately infused into the DNA strand of some other organism.
Native grown cotton is prone to infestation of larvae of insects resulting in low yield. It was observed that a certain bacterial infection of the cotton plant put off insects from the plant. Scientists identified the specific gene in the DNA strand of the bacteria (Bacillus thurangenesis or Bt) that made the plant insect-resistant. Gene modification method allows this gene to be deliberately inserted into the cotton plant’s DNA to produce a new strain of cotton, now termed Bt-cotton. This technology has widely been embraced in India leading to 90% of current cotton output being Bt-cotton. But there has so far been widespread public resistance to edible Bt-crop products like Bt-brinjal, Bt-corn, Bt-tomato and Bt-ladies finger for fear of adverse health implications.
In the 2012 ‘Seralini affair’, a French scientist Seralini had published a paper in a reputed scientific journal, reporting that genetically modified food caused cancer in laboratory mice. Mainstream media picked up on this report to publicize the findings. Even though later the publisher retracted the paper from the journal due to exposed flaws in the experimental design, the backlash against genetically modified crops has stayed on in public memory.
Rare Diseases
Rare diseases and disorders are considered so because of their rare occurrences (1 in 1,000 patients or less). The commonality of 7000-plus known rare diseases is lack of awareness, lack of access to diagnostic methods and lack of treatment options. The need of the hour is to raise awareness for such rare diseases and disorders and aim for an inclusive society that will bring such invisible patient-sufferers living on the fringes into the mainstream. ‘Join us in making the voice of rare diseases heard’ is the slogan of Rare Disease Day. The idea to observe the day originated in France, but is now being held in many countries including India.
Mr. Satish Srinivas descriping the perils and hopes of Alternating Hemiplegia of Childhood, a rare disease that affects 1 in 1 million population.
A couple of rare diseases from our own Chennai city are -
Alternating Hemiplegia of Childhood
Alternating Hemiplegia of Childhood (AHC) is an ultra-rare (1 in 100,000 people) neurological disorder that manifests as recurrent episodes of weakness or paralysis on either side of the body as well as on both sides of the body (the side affected might alternate with each recurrence). Many times the symptom is misdiagnosed as epilepsy and wrongly treated for it. The attack generally ceases with sleep. The onset of AHC is generally between birth and 18 months and persists into adulthood. Though cause of AHC is unknown, some triggers to the neurological episodes include bright or flashing lights, loud sounds, pool or bath water, excitement and more. In AHC, a specific gene ATP1A3 is mutated de-novo (at the time of egg or sperm production for the child) and is not inherited. Effects of AHC include cognitive and developmental delay, epilepsy or seizures, behavioral problems, problems involving involuntary movement of limbs as well as in swallowing and bowel control. There is no specific treatment for AHC, even though Duke University in the USA is in the research process of drug identification. Management of AHC involves physiotherapy, occupational therapy, speech therapy and special education for learning disabilities. Indian institutions like NIMHANS, Bengaluru and AIIMS, New Delhi, have pediatric neurologists who are familiar with AHC, its diagnosis and management.
Osteogenesis Imperfecta
Osteogenesis Imperfecta is a rare genetic disorder. It is a fragile bone disease due to defects in Col1A1 and Col1A2 genes. Col1 genes are responsible for collagen, which is an important protein in many organs of the body including bones. It affects 1 person in a population of 20,000. This disease results in the affected child’s physical development being compromised leading to bones that can easily break, short stature etc. No specific medical treatment is currently available for this rare disease.
Images: Anandhi N. & Navaneetham D