Understanding the Genetics Aging Process and Longevity

genetics and aging grandmother and grandson
Genetics and aging are closely related, because human aging begins on a cellular level. Human cells can only divide and replicate so many times. Science has established that the length of human life, and the number of times cells can divide and replicate, seems to be predetermined. In other words, our lifespan is in many ways determined by the genes we inherit from parents, grandparents and ancestors.
 
According to a 2005 New York Times article, fewer than two in every 10,000 people live to be 100 years old or older. Women by nature tend to live longer, but why? Evolution and gendered behavior may provide the answer. Men engage in riskier activities and more frequently engage in daredevil behavior. This explains why more men die in car accidents and violent encounters than women.

Understanding Genetics and Aging

Of course, genetics only influences human lifespan to a certain extent. There are many factors determined by an individual’s personal choices that can shorten or lengthen an individual’s life. For example, poor diet and excessive alcohol consumption can shorten a lifespan. In contrast, a healthy diet and moderate exercise can add years to a person’s life.
 
If your ancestors have a history of dying young, do not resign yourself to death at an early age. Similarly, if your relatives have lived well into their nineties, do not assume you are immune from disease, cancer or an early demise.

The Study of Aging

The study of aging, known as gerontology, has made much progress in the last three decades. Gerontologists have an improved understanding of the genetics aging process. Research will now provide future developments in preventing aging genetics and helping humans live longer.

Aging and Body Systems

Aging causes changes in all body systems which also increases risk for contracting various diseases. Gerontology can help scientists understand aging genetics in each body system as well as on a genetic, cellular level. Consider how certain organs and body systems change over time:
  • Arteries: Arteries thicken and stiffen as a person ages.
  • Bladder: Incontinence is common in aging people due to tissue atrophy.
  • Body Fat: Body fat decreases during aging and body fat moves deeper into the body.
  • Brain: Connections between neurons become less efficient with age. As a person ages, the brain shrinks in size. Subtle changes in cognitive abilities are common with age, as are memory lapses.
  • Hearing: People have increased difficulty hearing high frequencies as they age.
  • Heart: The heart muscle tends to thicken with age.
  • Immune System: The ability of T cells to function declines and these cells take longer to replenish. T cells are a type of white blood cell that protects a body from infection, and play a major role in the body’s immune system.
  • Kidneys: Kidneys become less efficient as a person ages.
  • Lungs: Lung capacity decreases with age.
  • Muscles: Muscle tone declines over time.
  • Sight: Humans have difficulty seeing up close as they age.

Progress in Aging Genetics Studies

Scientific studies in animals have demonstrated that progress of aging can be postponed or possibly even reversed, and therefore the human lifespan may be extended significantly. Progress has made valid observations, but not always useful conclusions. For example, a University of Chicago study found that people born in October and November have a longer life expectancy than people born in April, May or June. This may be an indication of seasonal vitamin deficiencies.

Controversy in Genetics and Aging

Progress and promising research in aging genetics is somewhat controversial and frequently met with skepticism. Skeptics either feel it is not desirable for humans to live longer or it is simply not possible. Critics also question how lengthened life spans would affect population sizes and use of the earth’s resources.
 
Resources
 
Fountain, Henry (2005). For centenarians, it all begins at birth. Retrieved August 27, 2008, from the N.Y. Times Web site: www.nytimes.com/2005/10/30/weekinreview/
30fountain.html?ex=1288328400&en=94a19bd340bcae16&ei=5088&partner=
rssnyt&emc=rss.
 
Health and Age (2001). How does the brain change with age? Retrieved August 27, 2008, from the Health and Age Web site: www.healthandage.com/html/min/afar/
content/other6.htm.
 
Hitti, Miranda (2006). Why do women live longer than men? Retrieved August 27, 2008, from the Web MD Web site: http://women.webmd.com/guide/20061201/why-women-live-longer.
 
Houghton Mifflin Harcourt Learning Technology (2002). Eat less, buzz longer? Retrieved August 27, 2008, from the riverdeep.net Web site: www.riverdeep.net/current/2002/
09/091602t_oldflies.jhtml.