In biology, a mutation is the alteration of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA. Mutations result from errors during DNA replication and meiosis, or other types of damage to DNA, which may undergo error-prone repair, or cause an error during other forms of repair, or else may cause an error during replication. Mutations may result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce discernible changes in the observable characteristics of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution and the development of the immune system, including junctional diversity; the genomes of RNA viruses are based on RNA rather than DNA. The RNA viral genome can be single-stranded. In some of these viruses replication occurs and there are no mechanisms to check the genome for accuracy; this error-prone process results in mutations. Mutation can result in many different types of change in sequences.
Mutations in genes can either have no effect, alter the product of a gene, or prevent the gene from functioning properly or completely. Mutations can occur in nongenic regions. One study on genetic variations between different species of Drosophila suggests that, if a mutation changes a protein produced by a gene, the result is to be harmful, with an estimated 70 percent of amino acid polymorphisms that have damaging effects, the remainder being either neutral or marginally beneficial. Due to the damaging effects that mutations can have on genes, organisms have mechanisms such as DNA repair to prevent or correct mutations by reverting the mutated sequence back to its original state. Mutations can involve the duplication of large sections of DNA through genetic recombination; these duplications are a major source of raw material for evolving new genes, with tens to hundreds of genes duplicated in animal genomes every million years. Most genes belong to larger gene families of shared ancestry.
Novel genes are produced by several methods through the duplication and mutation of an ancestral gene, or by recombining parts of different genes to form new combinations with new functions. Here, protein domains act as modules, each with a particular and independent function, that can be mixed together to produce genes encoding new proteins with novel properties. For example, the human eye uses four genes to make structures that sense light: three for cone cell or color vision and one for rod cell or night vision. Another advantage of duplicating a gene is. Other types of mutation create new genes from noncoding DNA. Changes in chromosome number may involve larger mutations, where segments of the DNA within chromosomes break and rearrange. For example, in the Homininae, two chromosomes fused to produce human chromosome 2. In evolution, the most important role of such chromosomal rearrangements may be to accelerate the divergence of a population into new species by making populations less to interbreed, thereby preserving genetic differences between these populations.
Sequences of DNA that can move about the genome, such as transposons, make up a major fraction of the genetic material of plants and animals, may have been important in the evolution of genomes. For example, more than a million copies of the Alu sequence are present in the human genome, these sequences have now been recruited to perform functions such as regulating gene expression. Another effect of these mobile DNA sequences is that when they move within a genome, they can mutate or delete existing genes and thereby produce genetic diversity. Nonlethal mutations increase the amount of genetic variation; the abundance of some genetic changes within the gene pool can be reduced by natural selection, while other "more favorable" mutations may accumulate and result in adaptive changes. For example, a butterfly may produce offspring with new mutations; the majority of these mutations will have no effect. If this color change is advantageous, the chances of this butterfly's surviving and producing its own offspring are a little better, over time the number of butterflies with this mutation may form a larger percentage of the population.
Neutral mutations are defined as mutations whose effects do not influence the fitness of an individual. These can increase in frequency over time due to genetic drift, it is believed that the overwhelming majority of mutations have no significant effect on an organism's fitness. DNA repair mechanisms are able to mend most changes before they become permanent mutations, many organisms have mechanisms for eliminating otherwise-permanently mutated somatic cells. Beneficial mutations can improve reproductive success. Mutationism is one of several alternatives to evolution by natural selection that have existed both before and after the publication of Charles Darwin's 1859 book, On the Origin of Species. In the theory, mutation was the source of novelty, creating new form
Renana Jhabvala is an Indian social worker based in Ahmedabad, active for decades in organising women into organisations and trade unions in India, has been extensively involved in policy issues relating to poor women and the informal economy. She is best known for her long association with the Self-Employed Women's Association and for her writings on issues of women in the informal economy. In 1990, she was awarded a Padma Shri from the Government of India for her contributions in the field of social work. In April 2012, she became Chancellor of Gandhigram Rural Institute, a Deemed University in Tamil Nadu, India. Renana Jhabvala was born in Delhi to the Booker Prize winning novelist and screenwriter, Ruth Prawer Jhabvala, well-known architect Cyrus S. H. Jhabvala, her grandparents were active in public life during the early to mid part of the twentieth century. Her grandfather, Shavaksha Jhabvala, was active in the early Indian trade union movement, her grandmother, Mehraben Jhabvala, in the emerging women's movement.
In February 2012 talk given at India International Centre, Renana spoke about the work of Mehraben, a dedicated organiser and advocate of women and the President of the All-India Women's Conference from 1965–68. Jhabvala was raised and schooled in Delhi and graduated from Hindu College, University of Delhi, in 1972 with a distinction in BSc Maths, she attended Harvard University to pursue an additional degree in BA Maths. She went on to the Yale University to pursue post-graduate studies in Economics. After completing her studies, Jhabvala joined SEWA in Ahmedabad, in 1977 as an organiser, she worked first with the women workers stitching quilts in the Muslim area of Ahmedabad where she was instrumental in forming the first Cooperative in SEWA. Her main work was organising women into SEWA as a trade union. In 1981, she was elected Secretary of SEWA under the leadership of Ela Bhatt and organised beedi workers, agricultural workers, garment workers, street vendors and many others to bargain for higher income, better working conditions, space to work and social security.
She was active in fostering the growth of SEWA across India, taking the experiences of the organisation to States like Madhya Pradesh and Bihar and most to Uttarakhand and West Bengal. Jhabvala was instrumental in forming SEWA Bharat, a National Federation of SEWAs now in nine States of India. In 1995, she started the national office in Delhi; when the women members of SEWA began expressing the need for basic infrastructure and housing, she was one of the founders of the Mahila Housing SEWA Trust. In 2002 she became the Chair of SEWA Bank and helped to increase finance for poor women in many parts of the country, she has been active at the international level, representing SEWA at the International Labour Organization in 1995 and 1996 during the discussion on Convention for Home Workers. At the South Asia level she was instrumental in forming HomeNet South Asia, bringing together organisations in India, Pakistan. Bangladesh, Sri Lanka and Bhutan working with women home-based workers, she is presently the Chair of HomeNet South Asia.
She is one of the founders and present Chair of WIEGO and has been active in the formation of international networks for women workers in the informal economy. In addition to organising women into trade unions and co-operatives she has been interested and involved in policy issues of poor women and of the informal economy, she has been active in many Government committees and task forces which have formulated policies ranging from National Policy for Street Vendors, to the Law for Social Security of Unorganised Workers, to policies for unorganised workers in various States. She has written on these issues in journals and newspapers and has co-authored seven books, she is married to Harish Khare. The couple has one son. Chairperson, SEWA Grih Rin Limited. Chairperson, SEWA Bank & Board member National Co-ordinator, SEWA Chairperson, SEWA Bharat Executive Trustee, Mahila Housing SEWA Trust Secretary, SEWA Member, UN Secretary General's High Level Panel on Women's Economic Empowerment in 2016-2017 Chairperson, WIEGO Chairperson, HomeNet South Asia Member, Steering Committee, Working Group on Urban poverty and service delivery system in the context of formulation of the 12th five-year plan under Ministry of Housing and Urban Poverty Alleviation, Government of India.
Member, Expert Group to recommend the detailed methodology for Identification of Families living Below Poverty Line in the Urban Areas, Planning Commission, Task Force on Affordable Housing, Ministry of Housing and Poverty Alleviation Member, Prime Minister's National Skill Development Council. Chairperson, Task Force on Workers in Unorganised Sector, Government of Madhya Pradesh. Member, Task Force on National Policy for Street Vendors. Chairperson, Group on Women workers and Child labour, National Commission on Labour, Government of India Member Council, Integrated Research for Action and Development Member, India Senior Energy Advisory Council, Sponsored by Shell Company Chancellor, Gandhigram Rural University Board member, Invest India Micro Pensions Board member, Institute for Human Development. New Delhi Board member, India De
Abhinav Singh Kashyap is an Indian film director and screenwriter. Abhinav Kashyap was born in Obra, Uttar Pradesh where his father, worked for the Uttar Pradesh Power Corporation, he is an alumnus of The Scindia School and completed his graduation in English Hons from Hansraj College, University of Delhi in 1995. He is the younger brother of director Anurag Anubhuti Kashyap. Abhinav Kashyap is married to lives in Mumbai with his two daughters. Before entering the film industry, he worked in several Indian television serials. In 2000, he was involved in writing the script of the film Jung, he worked as an assistant to film maker Mani Ratnam for the film Yuva. He wrote dialogue for the films Manorama Six Feet Under and 13B, he made his debut as a director in the 2010 action film Dabangg, which he co-wrote, along with Dilip Shukla. Bollywood actor Salman Khan and debutant actress Sonakshi Sinha played the lead roles in the film. Dabangg was released on 10 September 2010, his second film Besharam was released on 2 October 2013.
It was a commercial failure. Abhinav Kashyap on IMDb