Genetics represent the information you have from your ancestors about how to build your body.  Genes function like a blueprint:  detailing how to build each cell and tissue in the body.  Most of  the one hundred trillion cells in your  body have genes, identical genes, inherited half from your mother, half from your father at conception. The information you inherit is unique to you unless you are an identical twin. 

Genes contain long spirals of DNA, formed by four chemicals called nucleotides.  These four chemicals combine in different patterns and groups of patterns to make up your genetic code.  That is it:  only four pairs of chemicals shuffled in infinite patterns create all the diversity in the human race.

Genetics influence some things but not by any means most things about your health.  Eye color, potential height, voice quality, and bone structure are strongly influenced by genes.  Recent animal experiments have shown us, however, that genes do not determine all of those things once considered fixed. Two mice have been bred now with exactly the same genes, but to mothers who had different amounts of foliate in their diets.  The mice with adequate foliate were small and dark and the mice with inadequate foliate were obese and golden in color.  So genes do not even determine what we look like at birth.

Very few diseases are inherited entirely through genes.  Huntington's Chorea is a well known example of one which is.  You cannot inherit diabetes, heart disease or cancer.  What one inherits is the blueprints for making chemicals, the chemicals you rely on to create energy to detoxify, to make hormones and immune cells to build muscles and to generate energy for work.  The blueprints are there from birth, the same in each cell. 

The genetic information for making your eyes in contained in the cells of your liver, which obviously looks and functions quite differently.  Environment plays the major role in how our genes are expressed.  To convince yourself that this is true, think of the healthiest fittest person you know, someone who exercises regularly avoids toxic chemicals, loves her job, eats a healthy diet and laughs often with her friends and family.  Imagine her identical twin sister who works in a fast food restaurant, smokes, takes several  prescription drugs and hates fruits and vegetables, preferring to eat fast food and drink sodas twice a day.  The twin with healthy habits we all imagine as looking healthier, inside and out.  This will be true because she has created the environment in which her genes are less likely to express illness.

Most chronic problems, from heart disease to osteoporosis are a represent complex interactions between genes and the environment.  The goal for health is to find ways to switch off any tendencies we inherited toward illness.   Most genes in your body are switched off most of the time.  Genes with the ability to promote disease can usually be switched on or off by environmental factors.  Factors known to turn on harmful gene expression are hormone imbalance, cigarette consumptions, infection, chronic nutrient deficiencies, and environmental pollution.

The next few years will bring huge changes in how we use genetics in medicine.  Right now, we do not know quite enough to say that if you inherit a certain gene from your mother, you need a certain environment to optimize your health, but that may soon come.  Labs can now do genetic testing to learn what tendencies toward osteoporosis and inflammation you inherit.  The only reason to do any test is if the test result will lead to a change in something you do.  Medicine seems to be moving toward knowing how to work with your genetic uniqueness to create your optimum health.  For now, we know with certainty that a healthy diet, clean and happy environment and excellent nutrition are your best choices for optimizing the expression of your genes.

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