Think of the human genome as the instruction manual for our body. Present in every cell’s nucleus, it contains our entire deoxyribonucleic acid (DNA). This DNA holds all the genetic details needed for our growth and function.
The Structure Of DNA
Our DNA is a double-helix structure, like a twisted ladder. It has two strands, each made up of four substances known as ‘bases’. These bases are adenine (A), cytosine (C), guanine (G), and thymine (T). Each base on one strand matches with a specific base on the other—A with T, and C with G. Together, they make up around 3.05 billion base pairs in the human genome.
Decoding The Genome
While all humans share a similar sequence of base pairs, everyone’s genome is unique. Comparing our genome to a mouse’s or other species’ shows that our base pair order is distinctly human. But, it’s those tiny, individual differences in our genome that make us unique. The process of reading and noting these base pair sequences is termed genome sequencing. It’s like decoding our own unique genetic fingerprint.
The Journey Of Genome Sequencing
Back in 1990, a team of scientists embarked on an ambitious project to map the human genome sequence, known as the Human Genome Project. Fast forward to 2003, they managed to deliver the initial results of the full human genome sequence. While a small fraction of repetitive parts remained unsequenced, by 2023, they released the most recent complete version of the human genome, carrying only a 0.3% error rate.
The Cost of Sequencing
The expense of sequencing can vary, based on the desired precision and the techniques used. Since the first rough draft of the human genome was public, the goal for many companies has been to lower the cost. Today, a reasonably accurate “draft” of an individual genome can be produced for around $1,000 or less, approximately ₹70,000.
Approaches to Genome Sequencing
Genome sequencing has advanced dramatically, with large sequencers now able to handle thousands of samples at once. Several methods of genome sequencing exist, such as whole genome sequencing and next-generation sequencing, each offering unique benefits.
Benefits of Genome Sequencing
Thanks to the Human Genome Project, the process of whole-genome sequencing is now possible. Reading an individual’s genome to spot variations from the average human genome can provide valuable insights. These differences, or mutations, can give us information about a person’s predisposition or potential risk for certain diseases, their response to certain stimuli, and much more.
Before we discuss genome sequencing, Let’s first understand what is genomics.
Understanding Genomics
Genomics is a field of study that focuses on understanding an organism’s genetic or epigenetic sequences. These sequences, which can be entire or parts of genetic information, are analyzed to comprehend their structure and function. This is how we learn about the biological products derived from them.
Genomics and Health
When it comes to health, genomics looks at how molecular mechanisms interact with health treatments and environmental factors to cause diseases. Remember, human genomics isn’t the only kind that affects our health. Our human genome interacts with numerous other organisms – like plants, disease-carrying vectors, and disease-causing pathogens. So, genomics of all these organisms have relevance to human health.
Technologies
Besides the knowledge of genomics, we also look at technologies that utilize this knowledge. These technologies aid in deciphering the complex information that genomics presents us with.
Genomics Vs Genetics
Genomics is slightly different from genetics. While genetics focuses on studying heredity, genomics zooms out a bit and looks at all the genes and their functions. Essentially, genetics examines single genes and how they function and are composed. Genomics, on the other hand, studies all genes and their interconnections, attempting to understand their collective effect on an organism’s growth and development.
Applications Of Genome Sequencing
Diagnostics and Genomic Sequencing
Genomic sequencing is a powerful tool in modern medicine. It’s used for prenatal screening, allowing doctors to identify genetic disorders in unborn babies. Scientists are even using Crispr, a Nobel Prize-winning technology, to fix mutations that cause diseases in human genes. Another application of sequencing is liquid biopsies where small blood samples are checked for DNA markers to detect early signs of cancer.
Genomic Sequencing in Public Health
In the public health arena, sequencing has proven its merits by decoding virus codes. In 2014, a scientific research team from M.I.T and Harvard used sequencing to examine Ebola samples from African patients. The genomic data from the virus helped to unveil unsuspected transmission pathways, opening up new strategies to control and prevent the spread of the infection.
As sequencing becomes more affordable, we could potentially sequence every human’s genome as part of everyday healthcare, leading to a deeper understanding of our individual health profiles.
Population Level Benefits
Expanding genomic sequencing to the population level could also reap significant benefits. By collecting and analyzing genomic data from large populations, we could gain a deeper understanding of disease factors and uncover potential treatments. This approach can be particularly powerful for rare genetic diseases, where large data sets are needed to pinpoint statistically significant correlations.
Genome Sequencing During The Pandemic
Genomic Sequencing at the Outset of the Pandemic
At the dawn of the pandemic in January 2020, a Chinese scientist named Yong-Zhen Zhang sequenced the genome of the new pathogen causing infections in Wuhan. According to a New York Times report, Zhang shared this crucial information with his virologist friend Edward Holmes in Australia. Holmes then posted the genomic sequence online.
The Use of Genomic Data in Pandemic Response
The published genomic sequence proved instrumental in the battle against COVID-19. Virologists, epidemiologists, and pharmaceutical firms started studying the sequence. They were learning how to fight the virus, tracking its mutating variants, understanding their spread and intensity, and developing a vaccine. The genome sequence was also key in creating diagnostic PCR machines.
The Study of Emerging Variants
To respond effectively to the COVID-19 pandemic, researchers had to keep an eye on new variants. They needed to study how easily they spread, whether they could avoid the immune system, and if they caused severe disease. Genomic sequencing played a crucial role in these studies. It helped understand if specific mutations made the virus more infectious.
Implications of Mutations for Vaccines
Certain mutations could enable the virus to evade antibodies. This concept, known as immune escape, has significant implications for vaccines and their manufacturers.
Scaling Up of Genomic Sequencing
As the pandemic progressed, countries like the United States and the United Kingdom increased their genomic sequencing efforts. They tracked new variants and used this knowledge to take timely action.
Setting Up A Sequencing Framework By India
India implemented a sequencing framework to combat the spread of coronavirus. The main player in this initiative was the Indian SARS-COV-2 Genomics Consortia (INSACOG). This is a network of labs throughout the country, whose job was to examine coronavirus samples.
- INSACOG’s Focus on Variants of Concern: INSACOG’s main mission was to detect international ‘variants of concern’ (VoC). These are variants identified by the World Health Organization as being highly infectious. Any samples from international travelers who tested positive for the virus were sent to INSACOG for variant identification.
- Sequencing Efforts and Results: By the start of December in 2021, INSACOG had sequenced around a lakh samples. The consortium also had the responsibility of identifying if certain mutation combinations were increasingly prevalent in India.
- Sequencing in the Later Stages of the Pandemic: In the later stages of the pandemic, around December 2022, sequencing played a crucial role. At this point, more than 90% of the adult population was fully vaccinated and over a quarter had received a booster shot. Sequencing helped target efforts to curb infections. The Health Ministry encouraged states to increase sequencing (instead of testing) to track the evolution of new virus variants.
Genome India Project
The Genome India Project is a scientific endeavor that draws inspiration from the globally recognized Human Genome Project (HGP). The HGP was an international effort, successfully decoding the entire human genome between 1990 and 2003.
- Launch and Aim: Launched in 2020, the Genome India Project has a specific aim. It seeks to understand the unique genetic variations and any disease-causing mutations found within the highly diverse Indian population.
- Objective and Benefits: Researchers anticipate gaining key insights by sequencing and analyzing these genomes. The ultimate goal is to uncover genetic reasons behind diseases and create more personalized, effective therapies.
- Collaboration and Leadership: The Genome India Project is a collaborative effort involving 20 different institutions across India. The Centre for Brain Research at the Indian Institute of Science in Bangalore is spearheading this initiative.
The Need For An Indian Genome Database
India’s diverse population, with over 4,600 distinct population groups, holds unique genetic variations. These variations often amplify disease-causing mutations within specific groups. A database of Indian genomes will allow researchers to study these unique genetic variations, which could lead to customized drugs and therapies tailored specifically for India’s diverse ethnic groups.
- International Comparison: Countries like the UK, China, and the US have already initiated programs to sequence over 100,000 genomes. These databases help them understand their population’s genetic makeup and develop targeted healthcare solutions. India, despite its large population and diversity, lacks such a comprehensive genetic database.
- The Project and Its Impact: Around 20 institutions across India are collaborating on this project, led by the Centre for Brain Research at the Indian Institute of Science (IISc) in Bangalore. The project aims to uncover the genetic roots of chronic diseases that are currently on the rise in India, including diabetes, hypertension, cardiovascular diseases, neurodegenerative disorders, and cancer. By doing so, it will allow for the development of more effective treatments and prevention strategies.
Challenges Of Genome India Project
- Issue of Scientific Racism: The Genome India Project (GIP) could boost scientific racism and endorse stereotypes based on heredity and race. Past scientific work used these types of studies to support slavery and other discriminations. India’s identity politics could be further split by genetic mapping.
- Privacy and Data: The project triggers questions about privacy and data storage. Without a proper data privacy law in India, it’s hard to ignore the potential misuse of genetic information gathered by the GIP.
- Ethical Dilemmas: The project brings up ethical issues. It could lead to doctors performing private gene modification or selective breeding. These practices are always under scrutiny. The sentencing of a Chinese scientist in 2020 for creating the first gene-edited babies shows how crucial these concerns are.
The Human Genome Project
The Human Genome Project (HGP) stands as a landmark in scientific history. It’s like an epic journey of biological exploration undertaken by a team of international scientists. Their mission? To delve deep into the DNA, or genome, of certain organisms.
- When Did It Happen?: This monumental project kicked off in October 1990 and concluded in April 2003.
- What Did It Achieve?: The crowning achievement of the Human Genome Project was to produce the first-ever sequence of the human genome. This is essentially a blueprint of a human being.
- How Did It Impact Us?: This significant accomplishment has been a game-changer. It not only sped up our understanding of human biology but also led to major improvements in medical practice.
Understanding Global Inequality In Genomics
Global health issues are most severe in poor and middle-income nations, while advanced treatments are often only available in richer countries. This imbalance also impacts genomics, a vital branch of science.
- The Genomic Divide: There’s a significant gap in genomics between wealthy and poorer nations. Why? Many reasons play a part. Poor countries often lack the funds, health services, and infrastructure to carry out genomic research. Also, they may have more pressing health concerns, like tackling diseases such as TB and HIV/AIDS.
- Bridging the Gap in Genomics: Advancements in genomics can help close this health gap, but this requires a balanced global effort. Equal financial investment, global clinical research, and fair access to genomic services are crucial. Sharing information, expertise, and technology between rich and poor countries can accelerate this process.