Reasons for Referral to Genetics

Reasons for Referral to Genetics

Prenatal or preconceptional patient who is or will be:
* Age 35 years or older at the time of delivery (for a singleton pregnancy)
* Age 33 years or older at the time of delivery (for a twin pregnancy)
* A close blood relative of her partner (consanguineous union)

Prenatal or preconceptional patient who has:
* An abnormal first or second trimester maternal serum nuchal translucency screening test
* Exposure to a teratogen or potentially teratogenic agent during gestation such as radiation, high-risk infections (cytomegalovirus, toxoplasmosis, rubella), drugs, medications, alcohol, etc.
* A fetal anomaly or multiple anomalies identified on ultrasound and/or through echocardiography
* A personal or family history of pregnancy complications known to be associated with genetic factors such as acute fatty liver of pregnancy

Either member of the couple with:
* A positive carrier screening test for a genetic condition such as cystic fibrosis, thalassemia, sickle cell anemia, Tay-Sachs, etc.
* A personal history of stillbirths, previous child with hydrops, recurrent pregnancy losses (more than two), or a child with sudden infant death syndrome (SIDS)
* A progressive neurologic condition known to be genetically determined such as a peripheral neuropathy, unexplained myopathy, progressive ataxia, early onset dementia, or a familial movement disorder
* A statin-induced myopathy

Either member of the couple with a family or personal history of:
* A birth defect such as a cleft lip palate, spina bifida, or a congenital heart defect
* A chromosomal abnormality such as a translocation, marker chromosome, or chromosomal mosaicism
* Significant hearing or vision loss thought to be genetically determined
* Mental retardation or autism

Genetic consultation may be helpful under the following circumstances for adult patients with a personal history of:
* Abnormal sexual maturation or delayed puberty
* Recurrent pregnancy losses (RPLs) (more than 2)

Cystic Fibrosis
Ashkenazi Jewish Screening
Fragile X Syndrome
Factor V Leiden

There is growing consensus that testing should be performed in at least the following circumstances (these are the same general recommendations for testing for any thrombophilia):
* Venous thrombosis in pregnant women or women taking oral contraceptives.

Testing may also be considered in the following situations:
* Relatives of individuals known to have factor V Leiden. Knowledge that they have factor V Leiden may influence management of pregnancy and may be a factor in decision-making regarding oral contraceptive use.
* Women with recurrent pregnancy loss or unexplained severe preeclampsia, placental abruption, intrauterine fetal growth retardation, or stillbirth. Knowledge of factor V Leiden carrier status may influence management of future pregnancies.

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Rates of Autism in Fragile X syndrome

Rates of Autism in Fragile X syndrome (FXS)

FXS OVERVIEW
* Fragile X syndrome (FXS), also called Martin-Bell syndrome, is the most common type of inherited intellectual disability
* An inherited condition that is passed down from parents to child, due to a single gene mutation. The abnormal gene is located in the X chromosome.
* About one out of 4,000 males and one out of 8,000 females are born with FXS each year in the United States.
* Mothers with the mutation have 50% chance of passing the gene to their children of both sexes, whereas fathers can only pass it to their daughters.
* Severity of the condition depends on the number of gene repetition.
* patients with FXS experience some combination of symptoms that affect their mental, physical, social, and sensory characteristics. Females with FXS often experience milder symptoms than males.

(http://www.wellness.com/reference/conditions/fragile-x-syndrome-fxs/symptoms-and-causes)

GUILTY GENE
* One in 250 females and 1 in 500 males carries the FMRl gene in a pre-mutation state.
* Located on the long arm of chromosome X, in the q 27.3 region.

CHARACTERISTICS OF FRAGILE X SYNDROME
* FXS has different effects on males and females. Males tend to be more affected than females.
* Intellectual disabilities. ranging from mild to severe. Low IQ score (40-75 for males). Female’s intellectual abilities is considered mild to moderate ,to a relatively normal mental development .
* Physical characteristics:
* elongated face or jaw
* larger ears,
* short stature
* Physical characteristics are usually normal for infants and young children.
* They become noticeable around the 11th year, and become clearly distinct during puberty.
* http://www.wellness.com/reference/conditions/fragile-x-syndrome-fxs/symptoms-and-causes

CHARACTERISTICS OF FRAGILE X SYNDROME
* Social and emotional disabilities:
* Anxiety which leads to avoidance behavior and health issues (heart palpitations, faintness, blushing, and profuse sweating)
* Attention deficit
* Anger issues
* Aggressive behaviors (males)
* Language development: Males and females have different language development
* Difficulty understanding social cues, body language, tone of voice, or facial expressions

CHARACTERISTICS OF AUTISM
* Autism is a behavioral diagnosis with no bio-marker.
* Impaired social interaction
* Impaired communication
* Restricted interests
* Repetitive behaviors

PREVALENCE OF FXS IN AUTISM
* FXS can cause a child to have to have Autism or ASD. However not all children with FXS have Autism
* Between 2% and 16% of all children diagnosed with autism.
* Approximately one-third of all children diagnosed with fragile X syndrome also have some degree of autism.
* Fragile X syndrome is the most common known single gene cause of autism (http://www.fragilex.org/html/autism_and_fragile_x_syndrome.htm)

DIFFERENCES BETWEEN FXS AND AUTISM
FXS differs from autism in that it can be defined in terms of a specific biomarker: an abnormally expanded sequence of CGG repetitions at the fragile X site at Xq27.3. There is, however, a wide range of individual differences in the length of this triplet expansion, the completeness of the resulting DNA methylation, the levels of transcription and translation into FMR1 mRNA and FMRP, and the modulator effects of polymorphisms in the many genes whose products FMRP regulates.

REFERENCES

* Thomas Johnson, Vanessa A. Checklist Assessments Of FMRl Gene Mutation Phenotypes. Journal of Diversity, Vol, 15, No, 3 Fall 2008
* Belmonte, Matthew K & Bourgeron, Thomas. Fragile X Syndrome and Autism at the Intersection of Genetic and Neural Networks. Nature Neuroscience, Vol 9, No 10, October 2006.
* Feinstein, Carl and Reiss Allan L. Autism: The Point of View from Fragile X Studies. Journal of Autism and Developmental Disorders, Vol. 28, No. 5, 1998
* Brodkin,Edward S. Social Behavior Phenotypes in Fragile X Syndrome, Autism, and the Fmr1
Knockout Mouse: Theoretical Comment on McNaughton et al. (2008). Behavioral Neuroscience /American Psychological Association, 2008, Vol. 122, No. 2, 483–489.
* fragilex.org
* http://www.wellness.com/reference/conditions/fragile-x-syndrome-fxs/symptoms-and-causes


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Fragile X Syndrome

Fragile X Syndrome
By: Mary Beth Oliver, Megan Lawrence, Kayla Sink

An inherited disorder caused by a defective gene on the X-chromosome and causing mental retardation, enlarged testes, and facial abnormalities in males and mild or no effects in heterozygous females.

Cause/Origin
* In a normal cell there are 23 pairs of chromosomes.
* The first 22 pairs are the same in both males and females.
* The 23rd pair is what makes a person a boy or girl
* X and Y make a person a male and two X chromosomes make a person a female
* On the X chromosome is a gene that is known as FMR-1, this is where the mutation occurs and causes Fragile X
* The FMR-1 gene is thought to play an important role in the development of the brain
Video:
http://www.youtube.com/watch?v=wGdH1M5lCVY


Prevalence
* affects both males and females from all races and backgrounds
* more men are affected and tend to have more severe traits than the women
* more than 80% of males with Fragile X have an IQ of 75 or below
* women often have less severe impairments than men

Characteristics
* most common characteristics are mental impairments and learning disabilities
* long face and large ears
* problems with sensation, emotion, and behavior
* developmental delay and mental retardation
* speech delay and excessive tiredness
* autism or autistic-like behavior
* delayed motor development

Educational Implications
Calming techniques
* beanbag chair
* watching a video
* music
* have a “safe place” where students can go to on request and calm down

Modified Environments
* sit student near teacher and away from distractions
* be aware of noises
* activity level
* lights and sensory overload for each individual child

Structured plans
* display clear schedule in classroom
* have clear expectations
* picture schedules help visualize transitions

Appropriate cues
* visual cues for sequence of events
* timers
* countdowns

Interactive lessons
* short tasks
* opportunities to move around

Plan a sensory diet
* engage the student in an activity known to be calming such as wearing weighted clothing
* jumping on a trampoline
* brushing

Instructional Implications
* Make note of the activities that cause your student to become over stimulated
* Teach students how to organize their steps for a task and how to ask questions
* Use step by step instructions
* Use the “fill in” or “closure” technique opposed to a direct question.
Ex. Instead of asking “What was your favorite part of the story?” ask “When the boy jumped off of the wall….”

Instructional Implications
* Focus on student’s personal interests as much as possible when teaching.
* Having students or parents fill out an interest inventory can help you find ways to engage students in learning more effectively.
* Allow use of word processing when appropriate.
* Use concrete objects and realistic contexts.
* Pause during verbal presentations to give more process time.
* Give alternative methods for responding

Other Professionals Involved
* The school's social worker or counselor can help students create plans and set goals for maturing their social skills.
* The occupational therapist, physical therapist and speech pathologist may work together to come up with a multi-dimensional plan for students with fragile X.
* Be an advocate for you student and make sure they are receiving the services that they are entitled too.

FYI
* Achievement tests tend to be better measures of students abilities because students with Fragile X tend to perform better than predicted by IQ tests.
* Students with fragile X often have a strong need for closure and perfection.
* Students with fragile X often experience a longer “rest” from learning or plateau, but do not take this as the student’s peak of intelligence. Students with fragile X need this rest time to take in their material and will continue to learn throughout their whole life.
* There is no cure for fragile X, but treatment and intervention strategies are available for the various symptoms of fragile X.


Resources

* http://www.youtube.com/watch?v=wGdH1M5lCVY
* http://www.medicinenet.com/fragile_x_syndrome/article.htm
* http://www.flickr.com/search/?q=fragile+x+syndrome
* http://www.emedicine.com/ped/topic800.htm
* http://geneticsmodules.duhs.duke.edu/Design/images/fragileX.jpg
* http://www.fragilex.org/html/home.shtml
* http://www.nichd.nih.gov/health/topics/fragile_x_syndrome.cfm
* Lesson Planning Guide for Students with Fragile X: http://www.fragilex.org/FXSBinderReprint0804.pdf


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