1. Jacquelin Ho
Period 2
April 7th
, 2014
FRAGILE X SYNDROME

2. Introduction
History:
1943 Martin/Bell discover X-linked form of
mental retardation,
1969 Herbert Lubs develops chromosomal
test to identify Fragile X,
1991 FMR1 gene causing Fragile X syndrome
is discovered (World, 2012).
Current presence:
1 in 250 females and 1 in 800 males carry the
mutation, and it affects all ethnic groups
(Hagerman et al., 2004)
According to the US National
Library of Medicine (2012),
Fragile X Syndrome is a mutation
affecting the X chromosome.
The mutation involves
abnormally high amounts of the
repeat of CGG in the FMR1 gene:
55-200 repeats: carrier
>200: full mutation, FMR1 ceases
to function
(Hagerman P., Hagerman R.,
2004)
It is known as the most common
form of inherited mental
retardation.

3. Symptoms and
Treatment
- Normal at birth
- Delayed development
- Mental impairment
- Attention deficit or
hyperactivity
- Frequent ear/sinus
infections
- Nearsightedness
- Lazy eye
- Seizures
Treated with:
- Speech, occupational, or
physical therapy
Currently no cure
(Sherman et al., 2005)
http://jmg.bmj.com/content/39/3/200/F1.large.jpg

4. Prevention and
Inheritance
Females can only inherit Fragile X from either
parent.
Males can only inherit the Fragile X gene
from their mother.
Fragile X is a mutation
associated with the X
chromosome.
Men carrying pre-mutations of
Fragile X are usually stable
(Sherman et al., 2005).
Males affected by Fragile X
espoused to healthy females
will have carrier daughters and
healthy sons.
Females carriers espoused to
healthy males may have
affected sons. (See Figure on
right)
http://upload.wikimedia.org/wikipedia/commons/a/a3/XlinkRecessive.jpg

5. Personal Reflection
Like many other mental disorders, people affected by Fragile X
syndrome are at risk of aggression, emotional instability, and autism.
Though there is currently no cure, various support programs are
available for those diagnosed with Fragile X and family members and
caretakers of the affected individual.
Fragile X is surprisingly common, even more so considering
how many people affected or carrying it are unable or simply choose to
not reproduce and avoid the risk of passing the disorder on to their
children.
In researching Fragile X, I was moved by words of advice and
the optimistic outlook of mothers caring for their autistic children. A
strong bond of fellow caretakers has developed across the internet.
General themes that appear in their stories include perseverance and
unconditional love.

6. Article Analysis Though autism is a common
symptom for those with Fragile X, new
studies show that the autism associated with
Fragile X differs from what is normally
observed.
Young autistic boys with and
without Fragile X were observed in a recent
test study. Those with Fragile X tended to be
more interested in social contact though
ended up shying away due to anxiety.
This study also shows why normal
treatment for autism has shown to not be as
affective in the case of Fragile X autism.
Wright, J. (2014, March 21).
Clinical research: Symptoms of
fragile X, autism
diverge. Simons Foundation
Autism Research Initiative.
Retrieved April 7, 2014, from
https://sfari.org/news-and-
opinion/in-brief/2014/clinical-
research-symptoms-of-fragile-
x-autism-diverge

7. References
Fragile X syndrome. (2012, April 12). In World of Genetics. Gale. Retrieved
from http://ghr.nlm.nih.gov/condition/fragile-x-syndrome
Hagerman, P., & Hagerman, R. (2004, August). National Center for
Biotechnology Information. Retrieved April 6, 2014, from
http://www.ncbi.nlm.nih.gov/pubmed/15052536?dopt=Abstract
Sherman, S., Pletcher, B., & Driscoll, D. (2005 October). Result
Filters. National Center for Biotechnology Information. Retrieved April 6,
2014, from http://www.ncbi.nlm.nih.gov/pubmed/16247297?
dopt=Abstract