In addition to smoking for most of her life, Madame Calment was also fond of Port wine and chocolate (more than two pounds of chocolate a week). She’s not the only one. Studies have failed to find healthy lifestyle choices to be the common thing between centenarians. As Nir Barzilai, who studies healthy Jewish centenarians, put it: “It’s not the yogurt.”Instead, scientists have discovered that longevity is prevalent in certain families and the focus is now on discovering the genes, or the DNA instructions, that favour a long, healthy life.In animals like mice, flies and roundworms, scientists have discovered a remarkable impact of genes on the ageing process. Hundreds of tiny instructions in the genome have been found to regulate longevity. In nematode worms, a mutation on the daf-2 gene can lead to a doubled, but still healthy lifespan. In tiny roundworms, the current record is a subtle change in the age-1 gene that extends lifespan ten-fold. If this could be applied to humans, it would mean people living more than 1,000 years.Life-extension effects from genetic engineering, however, tend to be more modest in mammals, though there is still evidence of health benefits. In mice, mutating the growth hormone receptor gene, which is crucial for regulating growth and cell proliferation, results in dwarf animals that not only live 40 per cent longer than normal but are protected from age-related diseases, like cancer, and exhibit a later onset of degenerative changes. In this example, it’s like the whole mammalian ageing process is retarded by changing a single gene.(independent.co.uk)Bakudaily.Az