fragile syndrome
TRANSCRIPT
FRAGILESYNDROME
Gopal Singh Charan
Lecturer, SGL Nursing Institutes
Semi, Jalandhar X-linked diseases:
X-linked diseases are those for which the gene is present on the X chromosome.
X-linked diseases show inheritance patterns that differ from autosomal diseases.
This occurs because males only have one copy of the X chromosome (plus their Y
chromosome) and females have two X chromosomes. X-linked genes are never passed from father to son.
The Y chromosome is the only sex chromosome that passes from father to son.
Males are never carriers – if they have a mutated gene on the X chromosome, it will be
expressed. Males are termed hemizygous for genes on the X chromosome.
FXS DEFINITION:
Fragile X syndrome (Marker X syndrome ) is a genetic condition involving changes in the long
arm of the X chromosome. It is characterized by mental retardation.
INCIDENCE
• Affects 1 in 3,600 males & 1 in 4,000- 6,000 females
• 1 in 260 women are carriers
• 1 in 800 men are carriers
• Fragile X appears in all socioeconomic background
• In Alabama, carriers and full mutations are estimated at 15,978
• Second only to Down’s Syndrome as a genetic cause of mental retardation
• Unlike Down’s Syndrome, maternal age is not a factor
• The most common known cause of autism
• About 30% of individuals with Fragile X Syndrome have autism
• 2-6% of individuals with autism have Fragile X Syndrome
• Both Males and Females Can Have Fragile X Syndrome
BOYS
Approximately 85% of boys with F.M. have cognitive defects in the MR range (below 70) . The
production of FMR1 protein is usually shut down
GIRLS
Approximately 70% of girls with F.M. have cognitive defects in borderline to M.R. range (below
70). Girls with more protein-producing cells tend to have higher IQs
CAUSES OF FRAGILE X SYNDROME
Fragile X syndrome is a genetic disorder passed from parent to offspring through DNA.
It is caused by mutation of the FMR1 gene (Fragile X mental retardation 1) on the X
chromosome.
This mutation is the result of a trinucleotide repeat disorder.
A section of the FMR1 DNA usually repeats a sequence known as CGG (cytosine,
guanine & guanine) 30-55 times. For someone with Fragile X syndrome, this section
repeats itself 200-800 times.
This causes the FMR1 gene not to produce the FMRP (Fragile X mental retardation
protein
Mutation of this gene can vary between premature mutation and full mutation.
Other disorders associated with this gene mutation:
fragile x associated tremor/ataxia
fragile x associated POF (premature ovarian failure
CLINICAL FEATURES
Macrotia (Large ears)
Long, narrow face Prominent forehead
Prominent, square chin
High palate (roof of mouth) Hand calluses
Mitral valve prolapse (a leaky heart valve)
Seizures
Eye problems Macroorchidism
Ear infections
Flat feet Hyper extensible joints
Eye problems in 20%-25%:
Refractive errors Strabismus
Astigmatisms
Seizures Missing developmental milestones
COMMON DIFFICULTIES
Sleeping
Toilet training
Socialization
Play
Cognitive The Fragile X mutation affects brain development and leads to a range of cognitive
delays.
Developmental delays
Mental impairment
Learning disabilities
Difficulties with frontal lobe functions (“executive” functions):
Organization of information:
Acting on that information in an effective manner
Focusing attention
Forming a plan and carrying it out
Behavior:
• Attention deficits
• Hyperactivity
• Impulsivity
• Autistic-like behaviors
• Repetitive behaviors
• Hand flapping
• Hand biting
• Gaze aversion
• Extreme anxiety, shyness
• Transition problems, difficulty adjusting to change
• Cognitive/ Behavioral Strengths
• Strong visual memory
• Long term memory
• Good verbal imitative skills
• Desire to be social
• Strong appreciation of humor
• Often receptive to helping or working cooperatively
• Speech and Language :
• Sensory Processing:
• Sensory processing often seen in infants and young children:
• Gross Motor problems.
• Fine Motor problems.
• Early/ Preschool Interventions:
• Speech and language therapy
• Occupational therapy
• Occasional physical therapy
• Settings with consistency, structure and routine
• Total communication program
• Simultaneous not sequential
• Visual learners
• Incidental learners
Suggested Recreational Opportunities
• Trampolines
• Bicycling
• Swimming
• Bowling
• Soccer
• Gym/Fitness Center
• Softball
• Martial Arts
• Scouts
• Choirs or other musical venues
• Special Olympics
• Challenger sports
Medications
• Attention-related problems
• Hyperactivity/ impulsivity
• Mood disorders/ depression
• Anxiety/ panic
• Aggression
• Obsessive/ compulsive symptoms
• Bedwetting
• Sleep disorders
• Seizures
• Self injury