快猫短视频

IF YOUR parents live to a ripe old age, you stand a good chance of doing the
same鈥� especially if you are female and survive the rigours of youth, say
researchers in Lyon.

Amandine Cournil and colleagues at Claude Bernard University looked at 643
families in the Valserine Valley in France, whose birth and death records could
be traced back to 1745. Comparing the life expectancy of 55-year-old offspring,
they found that those whose parents had reached the greatest ages could look
forward to a longer life. The effect was pronounced in women, who could look
forward to, on average, 3.6 years more than their contemporaries. 鈥淟onger-lived
parents beget longer-lived children,鈥� Cournil says.

Less than four years may not sound like much, but it does seem to settle a
long-running controversy about whether longevity is inherited. Some studies
have suggested that it is; others have disagreed. But it depends how you
measure longevity, she says.

By looking only at the life expectancy of people who reached 55, Cournil
could exclude a number of confounding factors. Death in childbirth, for example,
reduces the average female lifespan. But once women in particular reach 55,
other risk factors take over. The study results suggest that resistance to such
risk factors is inherited.

鈥淲e must be careful with a study such as this, because there might always be
environmental explanations,鈥� Cournil cautions. But 90 per cent of the population
were farmers throughout the period she studied, and there were few environmental
or economic differences. Cournil suspects that if genes are responsible, they
might be imprinted, as fathers seem especially good at passing longevity to
their daughters.