Genetic
variation
not only enables us to answer questions such as where do we come from, how have
we migrated but it also enables us to understand how various kinds of diseases
and health parameters can be maintained.
In conversation
with ET Healthworld, Dr Partha P Majumder, Distinguished
Professor, National Institute of Biomedical Genomics,
Kalyani, WB, talks about the genetic variation that arises within
the group over a revolutionary period of time tends to remain within that
group. Edited excerpts:
How
does gene flow Impact a given population?
Human populations are structured in many ways; Firstly, we are socially structured and we tend to choose mates from our own groups. These groups are based on certain cultural linguistic and other parameters and because of these kinds of groupings, the genetic variation that arises within the group over a revolutionary period of time tends to remain within that group. However we are not a completely a closed group, we also choose mates from other groups and so there is gene flow from one group to another.
Over a long period of time there is some amount of administration of genes from one population into another population, however the genetic variation that arise within a population group tends to remain localised within that group and as a result of human populations grouping themselves and genetic variations that newly arise tend to remain within the group.
Between the groups there is a lot of genetic variation that one obviously sees. We need to understand where this variation comes from. Genetic variations also lead to different kinds of susceptibilities to diseases, responsiveness to various kinds of drugs. This is not to say that genes are the only factors that are responsible for providing susceptibility to diseases or to the maintenance of health or responses to drugs, environment also count but the genes in environmental factors interplay in different kinds of ways and we need to understand those to be able to understand. We need to use statistical methods as we are looking at group averages or group characteristics and to be able to find group characteristics different from one group to another we need to use statistical methods. Over a period of time what has happened is that the cost of identifying genetic variation has fallen. We are able to capture more and more genetic variations between groups and as a result of this we are better able to find relationships among groups and genetic structures of these populations.
How
does genetic variation help us in the understanding of various diseases?
Genetic variation not only enables us to answer questions such as where do we come from, how have we migrated but it also enables us to understand how various kinds of diseases and health parameters can be maintained. We become susceptible to various kinds of diseases and eventually it can lead to providing information about drug treatment solutions for various diseases. In that context we have also been looking at specific diseases in particular, our lab has been looking at head and neck cancers, primarily oral cancer of a particular kind called Gene Gual Buckle oral cancer. The reason why we are looking at this kind of cancer is because the oral cavity is very frequently affected in the cancer patient in India. One of the reasons why cancer of the oral cavity are so common is because of the way the tobacco is consumed.
Cancer is completely a genetic disease, if you look at the cellular molecular level, there are genetic diseases in the tumour tissue and therefore even if you are not born with a particular genetic change you acquire those genetic changes during your life course. What we really like to do is to figure out what are the genes that are altered recurrently or frequently and genes that drive a cell to become a cancerous tissue in the oral cavity. Recently we have had some good publications, findings and we have been able to identify genes that cause the tumour....
Source:
