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ISSN 0409-7467 CCSIRSIR NEWSNEWS Progress, Promise and Prospects VOL 60 NO 1 & 2 JANUARY 2010 CONTENTS Unravelling our Genetic Diversity Shanti Swarup Bhatnagar Prize Winner International Symposium CSIR NEWS Wishes Appointment its Readers a Very Happy New Year 2010 website: http://www.csir.res.in R&D HIGHLIGHTS Genetic Diversity in Indian Populations A New Door Opened Dr. P. Cheena Chawla home to more than one billion people, India is a land of A matchless diversity in diverse ways. With scores of culturally diverse communities inhabiting the nation, each portraying a different language, religion, set of customs and cuisine, India is not only ethnically distinct that is much apparent but the human populations of this country are also distinct at the level of genes — the hereditary material that is passed on from one generation to the next — thanks to novel findings of a joint team of Indian and American Lalji Singh (left) and Kumarasamy Thangaraj — The key Indian players whose scientists, with key players from the Centre for Cellular and work unravelled the genetic distinctiveness of different Indian groups Molecular Biology (CSIR), Hyderabad, India. The US researchers are from Harvard Medical School, the Harvard reconstruct the historical origins of human populations in School of Public Health and the Broad Institute of Harvard India. It is also the region of our genetic material, which and MIT. clearly points to the many genetic variations in human beings Interestingly, if we look at our genetic material that that make select individuals at a higher risk of certain diseases biochemically comprises the DNA molecule, any two as compared to others. unrelated individuals surprisingly differ just by 0.1%, as the For this study on ascertaining genetic variability across remaining 99.9% of DNA is completely identical. What an various human populations in India, about 5.6 lakh genetic irony then that all the amazing human diversity, at the level markers were analyzed across the genomes of 132 of genes, is individuals who were selected from 25 diverse groups in housed only in India that represented 13 states comprising all six language this variable, families, traditionally upper and lower castes, as well as tribal and apparently groups. An important revelation of the new study led by tiny, portion of Lalji Singh and David Reich, published in 24th September our DNA! It 2009 issue of Nature, is that different Indian groups is this region carry genomic material from two distinct ancestral of DNA, com- populations – the ‘Ancestral North Indians’ (ANI) who prising some are related to western Eurasians, from whom the Indian three million populations have inherited 40-80% of their ancestry and base pairs, that the rest from ‘Ancestral South Indians’ (ASI) who are not is a storehouse related to any group outside India. The ANI ancestry has of clues to a rich been found to be significantly higher in Indo-European source of in- than Dravidian speakers, which suggests that formation, and populations descending from ASI may have spoken a has today helped Dravidian language before mixing with populations Housed in the nucleus of every body cell, chromosomes are vehicles of our genetic material scientists to descending from ANI. 2 CSIR NEWS R&D HIGHLIGHTS India Cracks the Human Genome In a ground breaking work, CSIR spending Rs. 15 lakhs (US$ 30,000). Kingdom, France, Germany, Japan and scientists at the Institute of Genomics The IGIB scientists triumphantly China. The International Human and Integrative Biology (IGIB), New generated over 51 gigabases of data, Genome Project formally started in 1990 Delhi, have completed the first human using the most sophisticated sequencing and was completed in 2003, sequencing genome sequencing in India, setting the technology that enables massive parallel the genomes of Craig Venter, James stage for India’s entry into individual sequencing of millions of fragments of Watson and an anonymous Chinese genomics, which is poised to open new the genetic material, as small as individual. Till now, only 14 individual possibilities in disease diagnostics and comprising only 76 base pairs. These genomes have been sequenced treatment. The genome that has been small DNA fragment once sequenced, worldwide. CSIR could achieve this by sequenced is that of an anonymous are then mapped back to the reference adapting to new technologies and healthy individual from Jharkhand. While genome. This herculean task of finding effectively integrating complex the first human genome sequencing took the sequence of the entire human genetic information technology tools with over a decade, and a whopping 3 billion material, comprising three billion base analytical capabilities. US dollars to complete the task, CSIR pairs, was possible due to the CSIR The sequencing of the human has bagged the unique credit for supercomputing facility at IGIB. With genome would help us to understand the accomplishing the same in only 45 days, this achievement, India has become the variations at genetic level that make two sixth country after US, China, Korea, individuals different. More importantly, Canada and UK, to demonstrate the since there is an association between the capability of sequencing and assembling genetic variants and predisposition to a complete human genome. diseases, human genome sequencing Understandably, sequencing of the would be enormously important in human genome requires high diagnosis and management of various computational capability and diseases including cancer. Interestingly, technological know-how in handling the sequencing of the Indian genome has sophisticated machines and analyzing revealed a large number of hitherto huge volume of data. The first human unknown variations that include single genome sequencing initiative was nucleotide polymorphisms (SNPs) as conceived as early as 1984. In addition well as many insertion/deletions in our to the United States, the ‘International genetic material. Understanding the Human Genome Project Consortium’ functional role of these variations would, comprised geneticists from United for sure, throw light on identifying the markers linked to specific diseases, which could be specifically hunted for predicting diseases before they spell disaster. Earlier this year, CSIR scientists also completed the genome sequencing of zebrafish – an organism popularly used to model human diseases – that has half the size of the human genome. With this feat, India became the first country to sequence the wild type strain of The Supercomputing Facility at IGIB (top) and The triumphant Indian team (from left): Ashok Patowary, DNA Sequencing Machine (above) Vinod Scaria, Sridhar Sivasubbu and Ramya Purkanti zebrafish. JANUARY 2010 3 R&D HIGHLIGHTS Another Door Opened Genetic Diversity Mapped in Asia Housing 60% of the human inhabitants that for example, may bestow the populations from the same linguistic of planet Earth, Asia – the world’s individual an advantage of better group tend to cluster together, which largest continent – is a huge melting survival in a particular environment, or means that there is considerable pot of genetic diversity. The a disease-gene marker which could be relatedness within ethnic/linguistic contributors of this exceedingly rich tracked back in time to discover the groups. It has also revealed that there human resource are the scores of human population from where that was a south-to-north migration of East unknown ancestors who migrated altered/mutated gene may have Asians, which means that the majority from different parts of the world and originated. of East Asian gene pool has been settled down in this region over In this unique attempt 1,928 derived from Southeast Asia. thousands of years. unrelated individuals representing 73 According to the study, the most recent Ancestral human populations are populations from 10 countries and common ancestors of Asians arrived believed to have originally spread out 10 linguistic lineages from mainland first in India. Later, some of them from Africa, from where they slowly China, India, Indonesia, Japan, migrated to Thailand, and also South began to adapt different parts of the Malaysia, the Philippines, Singapore, to Malaysia, Indonesia, and the globe due to the pressures of climate, South Korea, Taiwan and Thailand Philippines. food and health conditions. The present were studied. The first group of settlers must genetic human diversity of the Asian For establishing genetic have gone very far south before they populations is all due to these best differences between two unrelated settled successfully. These included adapting individuals, who proved most individuals, scientists basically look at the Malay Negritos, Philippine fit to survive in a given place. It is the more than three million differences in Negritos, the East Indonesians, and the tracking down of the ancestry of the their genes. Variations at the level of early settlers of the Pacific Islands. human populations, through certain tell- single nucleotides, are commonly Later, one or several groups of people tale signs written in every person’s referred to as single nucleotide migrated North, mixed with previous genes, that has today empowered polymorphism (SNP). Therefore, it is settlers there resulting in various scientists to remarkably establish a link the tracking of genetic variations populations now known as between two geographically separated through human migrations that provide Austronesian, Austro-Asiatic, Tai- groups of people. clues to evolution of