Wednesday, 14 March 2012

Key to Longevity finally found?

The pursuit for long life duration or even immortality has been a consistent target since ancient history times, from the Elixr of Life to the modern concept of healthy living with appropriate diets and habits. Mankind has always been on the search for ways to prolong their life.

Recent scientific research has also been trying to unravel the "mystery" behind why certain individuals are able to live to ripe old ages of 100 or even beyond, namely the centenarians and supercentenarians. In a recent paper published by the New England Centenarian Study in the journal Frontiers in Genetics, a research conducted on 2 centenarians aging more than 114 years old revealed that the secret to extended life may be hidden in code of genetics.
The aging in humans can be influenced by an individual's living environment and conditions, personal lifestyle as well as genetic factors.(Tan, 2008) Especially stepping into the age of 90 years old to 110 years old, genes have a significantly stronger impact. especially in the suppression of expression of disability and other diseases that are related to age.(Sebastiani 2012)

The investigation involved mapping out the entire DNA sequence of 2 supercentenarians, one female and one male, both of which lived to ages older than 114 years old. And results of the investigation indicated that while centenarians and supercentenarians do not necesarily have vast differences in DNA sequence or have some special longetivity enable variants( longetivity-predisposing genes) compared to nonagenarians, they do show a comparable 1% entirely new variations which can lead to the discovery of new longetivity genes.

Furthermore, the results obtained are highly supportive of the presence of coding gene variations in close proximity to longevity-associated variants discovered in previous studies. And these findings have lead to a probable conclusions that some longevity-associated variants have the ability to counteract the effect of disease-predisposing variants and therefore lead to longer lifespan.(Andersen 2011). Some of the genes includes(Barzilai 2001) :
1. ApoE/ Apolipoprotein- Involved in the metabolism of lipoproteins( proteins with lipids attached). Has been identified with a high possibility of involving in Alzheimer's disease. A variant-E2 is much more common in centenarians.
2. HLA-DR/ Histocompatibility locus antigen- confers "better resistance to infection and inflammatory processes", highly expressed in older generations, especially centenarians.
3. PAI-1/Plasminogen activator inhibitor-1- The polymorphism presented can significantly reduce the chance of cardiovascular and cerebovascular disease as well as unhealthy formation of blood clots which can result in diseases such as stroke or cardiac arrest.

These identified genes have demonstrated variations in forms(polymorphism), and these individual "forms" have been providing more benefit than harm in terms of the effect on aging. Especially in terms of delaying or preventing the emergence of diseases that current medical technology has associated with aging. In so far that these variants can significantly affect age-related disease, it might eventually prevent or delay death due to these diseases, which in reality are the major concerns of life expectancy and elderly-care.

Further research and experiments are necessary to confirm these observations and identify the new potential life-extending genes. But the idea that specific genes exist within us that can control how and when we age is here to stay. And this might even offer a new insight on complicated early ageing conditions such as Progeria and hence lead to potential treatments and cures.

The End
Tan, Q., Zhao,J.H, Zhang,D, Kruse,T.A, and Christensen, K.(2008). Power for genetic association study of human longevity using the case-control design. Am.J.Epidermiol. 168,890-896

Andersen,S., Sebastiani,P., Dworkis, D.A., Feldman,L., and Perls, T.T.(2011). Health span approximates life span amongst many supercentinarians. J. Gerontol. A Biol. Sci. med, Sci. doi: 10.1093/gerona/glr223.

 Sebastiani P, Riva A, Montano M, Pham P, Torkamani A, Scherba E, Benson G, Milton JN, Baldwin CT, Andersen S, Schork NJ, Steinberg MH and Perls TT (2012) Whole genome sequences of a male and female supercentenarian, ages greater than 114 years. Front. Gene. 2:90. doi: 10.3389/fgene.2011.00090

Barzilai, Nir;Shuldiner, Alan R. S
earching for human longevity genes: The future history of gerontology in the post-genomic era. The 

Journals of Gerontology; Feb 2001; 56A, 2; ProQuest Research Library 
pg. M83.

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