© 2018 The Brooks Coleman White Foundation, Inc.

GENETIC SEQUENCING

Humans have 46 chromosomes, receiving 23 from each parent.  Chromosomes are made up of shorter strands of our DNA, or genes.  DNA looks like a long, twisting ladder and is composed of chemical compounds - Adenine (A), Cytosine (C), Guanine (G), and Thymine (T).  In addition, each genetic “letter” is then paired with another to create a base pair.  A always attaches to T, and C always pairs with G.  These base pairs are the “steps” of the twisting DNA ladder that you see in pictures (like above).  Within a person’s genome, or complete set of DNA, there are more than 3 billion base pairs.  And every cell in your body contains your entire genome.  Genetic sequencing is breaking down and analyzing your entire genome’s base pairs.

It is these genetic letters that ultimately tell your body how to work and what features to “express”.  For example, if your eyes are brown, it is because your inherited genes are arranged in a specific way that causes specific cells in your eyes to be brown. The arrangements of your genetic letters within your genes tell your body what proteins to produce.  Proteins are used to do most of the molecular work in your body.  Proteins can give cells a certain shape and function, eventually forming specific tissues and organs, like eyes.  Proteins also help cells with biological processes such as metabolism and homeostasis.  

Many variations from “normal” genes are found within the human genome.  Fortunately, the vast majority of these variations are found in sections of DNA that don’t affect a person’s bodily functions or attributes.  However, the variations that are found in stable genetic sequences (ones that do affect a person’s characteristics) can cause harm.  The term “mutation” is generally given to variations that are linked to specific human diseases.  These genetic mutations cause a different protein to be produced than what was needed, which causes cells to function improperly.  Leukodystrophy is caused by these genetic variation errors, which lead to incorrect protein production in nervous system cells, leading to impaired biological and neurological functions.  Geneticists will look for these genetic mutations when diagnosing the disease.

Genetic sequencing is thus very important for the diagnosis and potential treatment of leukodystrophy.  We encourage you to speak with your physician about screening and sequencing options to better inform you about the disease, prognosis, and eligibility for treatments and clinical trials.

Some information above was referenced from:

23andme.com

genomenewsnetwork.org