Bill Boss
University of New Hampshire - Manchester
Class of 2013

What is Fragile-X Syndrome?

Fragile X Syndrome (FXS) is a disorder in which the afflicted organism suffers from impaired intellect and mental processes and is a form of mental retardation. This syndrome can lead to learning difficulties, mental retardation, mood swings and autism. Fragile X Syndrome is an X linked disorder, and as such much more drastically affects men than women. It is usually passed down from carrier females to their sons, as afflicted males cannot pass it down to their sons but can pass it to their daughters. The disease is generally diagnosed at early stages of life at around age 3. The diagnosis begins to become clear when the child has impaired motor skills, flaps their hands and arms constantly, has mood swings/irritability, and very slow speech growth along with learning impairment. Physical symptoms of the disorder can be seen in the face and head structure or other parts of the body; Those that have Fragile-X Syndrome typically have broad foreheads with large everted ears, thickened nasal bridges, prominent jaws, extended or thin faces, and males may have macroorchidism.

An example of the general features exhibited by a Fragile-X Syndrome expressing individual:

Fragile X example.png
Image received from Wikimedia Commons; "This work of art is free; you can redistribute it and/or modify it according to terms of the Free Art License. You will find a specimen of this license on the Copyleft Attitude site as well as on other sites."

What gene is responsible, and where is it located?

Fragile-X Syndrome is caused by the FMR1 gene, which is located on the X chromosome.

FMR1 Location.png
Image taken from Wikimedia Commons: "This image is a work of the National Institutes of Health, part of the United States Department of Health and Human Services. As a work of the U.S. federal government, the image is in the public domain."

Research Questions:

  1. Which gene is involved?
  2. How is this disorder created?
  3. Are there gender differences in regards severity of the condition?
  4. Is the responsible gene/gene mutations present across species, if so how closely are the genes related to humans?

How does Fragile-X become expressed?
Fragile-X; Does Severity Differ Based Upon Gender?
Fragile-X Genomics Data