‘Gene’y for Increased Human Life Span

Life span can be defined as the period of time between the birth and death of any organism. The limits of the lifespan of each species appear to be determined ultimately by heredity. Locked within the code of the genetic material are instructions that specify the age beyond which a species cannot live given even the most favorable conditions. And many environmental factors act to diminish that upper age limit.

Much information concerning the inheritance of longevity, however, has come from the study of genealogical records of nobility and landed gentry. There are various types of studies of the inheritance of longevity - genealogical records, life insurance records, and family histories of the general population - each of which have limitations that restrict the applicability of the findings. The principle studies indicate, nevertheless, that the children of long-lived parents are more likely to be long-lived than the children of short-lived parents. Conversely, the immediate ancestors – parents and ancestors – of long-lived persons on the average are older at death than are the immediate ancestors of persons who die at a relatively young age. These studies support the conclusion, mentioned earlier, that longevity is determined in part by heredity.

- In 1960, Marshall W. Nirenberg, Har Gobind Khorana, and Robert E. Holley cracked the genetic code that all living cells use to translate the series of bases in their DNA into instructions for protein synthesis.

- In 1969, a Harvard Medical School team isolated the first gene.

- In 1970, researchers from the University of Wisconsin synthesized a gene. Hamilton Smith discovered the first restriction enzyme that cuts DNA at specific points.

- In 1977, Fred Sanger developed the DNA sequencing technology.

- In 1998, two research teams succeeded in growing embryonic stem cells. The genome of multi-celled animal – a worm called C.elegans – was decoded for the first time.

- In 2001, the sequence of the human genome was released, and the "post-genomic era" officially began

Now in 2003, Scientists at the California Institute of Technology in Pasadena have identified a generic mutation commonly found in people over 100 years old. A study has shown that centenarians are five times more likely to have the same mutation in their mitochondrial deoxyribonucleic acid (DNA).

The project involved research on 52 Italian centenarians. The researchers examined the mitochondrial DNA in the subjects’ white blood cell and established that 17 per cent of the centenarians had a specific mutation called C150T transition. In comparison, this mutation is relatively rare and is found only in 3.4 per cent of 117 people under the age of 99. It is believed that the common mutation in the same main control region is responsible for the age advantage enjoyed by some people.

The presence of the C150T mutation in centenarians may be the key that will enable human beings to avoid the ravages of ageing.