Fragile X Syndrome (FXS) is caused by a mutation on the X chromosome involving expansion of the CGG repeat in the FMR1 gene. This leads to hypermethylation and reduced production of the Fragile X Mental Retardation Protein (FMRP). Lack of FMRP results in excessive mGluR signaling and protein synthesis at synapses. FXS is characterized by intellectual disability, autism-like behaviors, and various physical features. Testing involves genetic tests like PCR and Southern blot. Treatment focuses on mGluR antagonists to reduce excessive signaling, with several drugs in clinical trials showing promise based on preclinical findings in animal models of FXS.
FRAGILE X SYNDROME ( FXS ) an inherited cause of mental retardation.shhhoaib
-FXS is a genetic syndrome that is the most widespread single-gene cause of autism and inherited cause of mental retardation.
- It is associated with the expansion of the CGG trinucleotide repeat affecting the Fragile X mental retardation 1 (FMR1) gene on the X chromosome.
- Resulting in a failure to express the fragile X mental retardation protein (FMRP).
-FMRP is required for normal neural development.
-Absence of FMRP leads to abnormalities in brain development and function.
FRAGILE X SYNDROME ( FXS ) an inherited cause of mental retardation.shhhoaib
-FXS is a genetic syndrome that is the most widespread single-gene cause of autism and inherited cause of mental retardation.
- It is associated with the expansion of the CGG trinucleotide repeat affecting the Fragile X mental retardation 1 (FMR1) gene on the X chromosome.
- Resulting in a failure to express the fragile X mental retardation protein (FMRP).
-FMRP is required for normal neural development.
-Absence of FMRP leads to abnormalities in brain development and function.
Fragile X syndrome causes mild to severe intellectual disability. It affects both males and females, but females usually have milder symptoms.
Symptoms include delays in talking, anxiety and hyperactive behaviour. Some people have seizures. Physical features might include large ears, a long face, a prominent jaw and forehead and flat feet.
Therapy can be used to treat learning disabilities. Medication may be used to treat anxiety and mood disorders.
Fragile X associated primary ovarian insufficiency
Fragile X associated decreased ovarian reserve
Fragile X syndrome and reproduction
evidence based
Dr.Anu.M - Mch Resident - Department of Reproductive Medicine and Surgery
Part 4 of "Science & Sexuality." What exactly is a female? a male? an intersex person? Some kinds of intersex people are chromosomal variants. What can we learn about sexual identity and sexual orientation from sex chromosomal variants? Who is Milton Diamond? John Money?
20150918 C.Izzi - 22q11.2 Microdeletion Syndrome: Understanding the Emerging...Roberto Scarafia
22q11.2 Microdeletion Syndrome:
Understanding the Emerging
Importance of this Syndrome
Dr.ssa Claudia Izzi
Centro di Diagnosi Prenatale
Dipartimento Ostetrico-Ginecologico
Azienda Spedali Civili di Brescia
Prader-Willi syndrome (PWS) is a multisystemic complex genetic disorder.
PWS is relatively common with an estimated prevalence worldwide in the range of 1 in 10,000 to 30,000 individuals
Prader-Willi syndrome is due to absence of paternally expressed imprinted genes at 15q11.2-q13.
PWS was first described by Prader et al. in 1956 and it is the first recognized disorder related to genomic imprinting in humans.
PWS affects males and females with equal frequency and affects all races and ethnicities
Inborn errors of metabolism- focusing on its predominant adult onset forms, neurological perspective, clinical & biochemical approach to diagnosis, and neuroimaging findings.
Fragile X syndrome causes mild to severe intellectual disability. It affects both males and females, but females usually have milder symptoms.
Symptoms include delays in talking, anxiety and hyperactive behaviour. Some people have seizures. Physical features might include large ears, a long face, a prominent jaw and forehead and flat feet.
Therapy can be used to treat learning disabilities. Medication may be used to treat anxiety and mood disorders.
Fragile X associated primary ovarian insufficiency
Fragile X associated decreased ovarian reserve
Fragile X syndrome and reproduction
evidence based
Dr.Anu.M - Mch Resident - Department of Reproductive Medicine and Surgery
Part 4 of "Science & Sexuality." What exactly is a female? a male? an intersex person? Some kinds of intersex people are chromosomal variants. What can we learn about sexual identity and sexual orientation from sex chromosomal variants? Who is Milton Diamond? John Money?
20150918 C.Izzi - 22q11.2 Microdeletion Syndrome: Understanding the Emerging...Roberto Scarafia
22q11.2 Microdeletion Syndrome:
Understanding the Emerging
Importance of this Syndrome
Dr.ssa Claudia Izzi
Centro di Diagnosi Prenatale
Dipartimento Ostetrico-Ginecologico
Azienda Spedali Civili di Brescia
Prader-Willi syndrome (PWS) is a multisystemic complex genetic disorder.
PWS is relatively common with an estimated prevalence worldwide in the range of 1 in 10,000 to 30,000 individuals
Prader-Willi syndrome is due to absence of paternally expressed imprinted genes at 15q11.2-q13.
PWS was first described by Prader et al. in 1956 and it is the first recognized disorder related to genomic imprinting in humans.
PWS affects males and females with equal frequency and affects all races and ethnicities
Inborn errors of metabolism- focusing on its predominant adult onset forms, neurological perspective, clinical & biochemical approach to diagnosis, and neuroimaging findings.
Whole Exome Sequencing at Stanford UniversityGolden Helix
Dr. Reza Sailani is a Research Fellow in the Genetics department at Stanford University. To provide an overview of his research, Sailani explains the following two recent studies he has conducted:
Association of AHSG with alopecia and mental retardation (APMR) syndrome: Alopecia with mental retardation syndrome (APMR) is a very rare autosomal recessive condition that is associated with total or partial absence of hair from the scalp and other parts of the body as well as variable intellectual disability. Here we present whole-exome sequencing results of a large consanguineous family segregating APMR syndrome with seven affected family members. Our study revealed a novel predicted pathogenic, homozygous missense mutation in the AHSG gene.
WISP3 mutation associated with Pseudorheumatoid Dysplasia: Progressive pseudorheumatoid dysplasia (PPD) is a skeletal dysplasia characterized by predominant involvement of articular cartilage with progressive joint stiffness. Here we report genetic characterization of a consanguineous family segregating an uncharacterized form of skeletal dysplasia. Whole exome sequencing in four affected siblings and parents resulted in identification of a loss of function homozygous mutation in the WISP3 gene leading to diagnosis of PPD in the affected individuals. The identified variant is rare and predicted to cause premature termination of the WISP3 protein.
Supporting Genomics in the Practice of Medicine by Heidi RehmKnome_Inc
View the webinar at http://www.knome.com/webinar-supporting-genomics-practice-medicine. In this presentation, Dr. Heidi Rehm, Chief Laboratory Director of the Laboratory for Molecular Medicine at Partners Healthcare and one of the Principal Investigators on ClinGen, elucidates the challenges of genomics in medicine and outlined the path to integrating large scale sequencing into clinical practice.
Chromosomal Abnormalities in a Male Partner Who was a Candidate for Assisted ...Apollo Hospitals
Cytogenetic analysis was performed according to standard methods on cultured cells obtained from the patient with low sperm quality in respect of morphology and motility. The patients were interviewed about their histories and their reproductive problems, family background, and possible consanguinity.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...GL Anaacs
Contact us if you are interested:
Email / Skype : kefaya1771@gmail.com
Threema: PXHY5PDH
New BATCH Ku !!! MUCH IN DEMAND FAST SALE EVERY BATCH HAPPY GOOD EFFECT BIG BATCH !
Contact me on Threema or skype to start big business!!
Hot-sale products:
NEW HOT EUTYLONE WHITE CRYSTAL!!
5cl-adba precursor (semi finished )
5cl-adba raw materials
ADBB precursor (semi finished )
ADBB raw materials
APVP powder
5fadb/4f-adb
Jwh018 / Jwh210
Eutylone crystal
Protonitazene (hydrochloride) CAS: 119276-01-6
Flubrotizolam CAS: 57801-95-3
Metonitazene CAS: 14680-51-4
Payment terms: Western Union,MoneyGram,Bitcoin or USDT.
Deliver Time: Usually 7-15days
Shipping method: FedEx, TNT, DHL,UPS etc.Our deliveries are 100% safe, fast, reliable and discreet.
Samples will be sent for your evaluation!If you are interested in, please contact me, let's talk details.
We specializes in exporting high quality Research chemical, medical intermediate, Pharmaceutical chemicals and so on. Products are exported to USA, Canada, France, Korea, Japan,Russia, Southeast Asia and other countries.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
3. FXS: X-Linked LD
(Lubs et al, 2012)
LD: 2–3% of the population in the
industrialized world (Male to female ratio: 1.3 : 1)
X-Linked LD: 5%–10% of LD in males.
FXS: 50% of X-linked LD. (Rousseau et al.,
1995).
160 X-Linked LD disorders: 102 genes, 81
syndromal & 35 non-syndromal; 78 mapped.
<400 LD autosomal genes have been
identified.
Fragile X syndrome (FXS): most described.
Multiple FXSs: FXS-A, FXS-E & FXS-F
4. FXSs:
>120 known fragile sites in the
human genome > 6 sites on X
chromosome > 3 linked to LD (Lukusa
& Fryns, 2008).
FXS-A = FSX = Martin-Bell
syndrome:
◦ Band Xq27.3. > CGG repeats
expansion > Gene (FMR1 & FMR4)
> Protein (FMRP) > classical FXS
FXS-E = FRAXE: (Gécz 2000)
◦ Band Xq27 > CCG repeats
expansion > Gene (FMR2 & FMR3)
(synonym AFF2) > Protein (???) >
non-syndromic X-linked LD
FXS-F = FRAXF:
◦ Band Xq28 > CGG repeats
expansion > Gene (???) > Protein
(???) > no clear phenotype has
been established.
6. FXS: History: 1
1938: Lionel Penrose first observed that more
males than females in the population have LD
(1.25:1) > X linked.
1943: Martin and Bell: described a described
a family with 11 members with X-linked LD
(fragile x symptoms) although they did not
know the cause > Martin-Bell Syndrome.
1953: Watson & Crick > DNA structure.
1969: Herbert Lubs: the first one to see the
"marker X chromosome" in LD patients.
1970: Frederick Hecht: coined the term
"fragile site“ > FXS.
1977: Grant Sutherland > Folate Deficient
Medium 199 >specific FXS test
JP Martin
H Lubs
7. FXS: History: 2
1991: Verkerk: FMR1 gene > FMRP
1991: Kerr et al > “Non‐specific X
Linked Mental Retardation” (XLMR).
1993: Ashley et al > Hyper-methylation
> silencing FMR1 gene
1990s: S Warren & Colleagues >
FMRP is a selective (suppressant)
mRNA-binding protein in dendrites.
1994: Bakker et al > FMR1-KO Mice
model generated.
1998: Murray et al > fragile X-
associated Premature Ovarian
Failure.(also called FXPOI)
S Warren
8. 2001: Hagerman et al > Fragile
X-associated Tremor/Ataxia
Syndrome (FXTAS)
2002: Huber et al > mGluR-LTD
exaggerated in FMR1-KO Mice
2004: Bear et al > mGluR
theory of FXS.
2005: Yan et al > MPEP
improves FXS in animals.
2009: Clinical trials in humans.
FXS: History: 3
Randi
J. Hagerman
13. FXS: The most common inherited LD
(Paluszkiewicz et al, 2011).
10% of undiagnosed male LD cases
3% of undiagnosed female LD cases
The most leading genetic cause of autism
(Paluszkiewicz et al, 2011).
Second most common cause of LD after
Trisomy 21 (Down Syn.) (Rousseau et al., 1995).
FXS related milder problems (e.g.
dyscalculia, dyslexia, social phobia, and
ADHD) may be more common than FXS
related LD (Hagerman et al, 2010)
Fragile X Syndrome: Statistics
Medscape reference 2013
14. Statistics: USA Medscape reference 2013
Male FXS: 1 in 2500-4000.
Male carriers: 1 in 250-800
Female FXS: 1 in 7000-8000.
Female carriers: 1 in 130-250
Females with FXS: less LD and
less physical characteristics.
Males with FXS: more likely to
be sensitive to environmental
factors.
Mortality rate: not affected
16. FXS: Aetiology
Medscape reference 2013
FXS Chromosomes >
constriction of band Xq27.3.
> site of “Fragile X Mental
Retardation-1 Gene” (FMR1)
FMR1 gene > produces
“Fragile X Mental Retardation
Protein (FMRP)
FMRP > a widely expressed
mRNA-binding Translational
Regulator with reportedly
hundreds of potential targets.
18. FXS: FMR1 gene
Medscape reference 2013
In FXS a full mutation
in the FMR1 gene >
◦ Hyper-methylation
of FMR1 gene >
◦ FMRP is not
manufactured:
(^Degree of
methylation >
^degree of severity
of FXS).
Most commonly 29 - 30 repeats
Premutation
Full Mutation
19. FMRP: regulatory protein of
messenger RNA (mRNA) in
neurons and dendrites
Lack of FMRP >
downgraded receptors in
synapses.
> suppression of neuronal
transmission
> slow transmission in the
brain cells
> poor brain development
FXS: FMR1 gene
Medscape reference 2013
20. 55-199 repeats:
PREMUTATION > enhanced
production of FMR1-mRNA (2–
8 times normal levels).
◦ > Primary Ovarian
Insufficiency (40s-50s)
◦ > Fragile X-associated
Tremor/Ataxia Syndrome
(FXTAS). (60s-70s)
200 repeats or more: FULL
MUTATION >
◦ Hyper methylation of the
repeats in the FMR1 region
>
◦ Reduced or absent FMR1-
mRNA >
◦ Decreased or absent
Fragile X Mental Retardation
Protein (FMRP) > FXS.
FXS: Mutations &
Premutation
22. FXS: Mode of Inheritance
Medscape reference 2013
Females with full mutation:
Unaffected – mildly affected (LD, autism
or physical features of FXS). (? X
Inactivation)
50% boys: FXS
50% girls: carriers with full mutation.
Females with premutations:
20-25%: Primary Ovarian Insufficiency.
4-8%: FXTAS
Increased risk of autoimmune disorders
(hypothyroidism & fibromyalgia).
CGG triplets are UNSTABLE > boys and
girls > full mutation or premutations.
23. Males with a full mutation:
Individuals: have full FXS.
Sons: are unaffected > only
get Y chromosome
Daughters: mutations or
premutation to one X
chromosome (sperm:
MOSAICS).
Most closely resembles X-
linked dominance with partial
penetrance (see Dobyns et al
2004).
FXS: Mode of Inheritance
Medscape reference 2013
24. Males with premutations:
Individuals:
◦ Unaffected
◦ Mild FXS (LD, autism or
physical features of FXS).
◦ 40%: FXTAS in old age.
Daughters:
◦ exact premutation (no
MOSAICS).
◦ FXPOI, FXTAS +/- mild FXS.
Sons: unaffected (only get
Y chromosome).
FXS: Mode of Inheritance
Medscape reference 2013
25. - Most patients
(98%) with FXS >
CGG triplet
expansion
- Few patients (2%)
> other
abnormalities e.g.
POINT MUTATION
or DELETION of
the FMR1 gene.
FXS: Mode of Inheritance
Medscape reference 2013
26. FXS: Mosaic Patterns
Mosaic patterns > common in males >
unstable number of repeats over
generations > pattern of inheritance
difficult to predict.
◦ (Allele) Size mosaic:
different sizes of the repeat expansion in
different cells.
Most common form of mosaic males.
◦ Sperm mosaic: different sperms have
different sizes of the repeat expansions.
◦ Methylation mosaic: Incomplete methylation
of a full mutation.
29. Fragile X-associated tremor ataxia
syndrome (FXTAS):
33-46% of men, with permutations, older than 50
years.
4-8% in older women with permutations .
Other signs of
neurodegeneration:
• Brain atrophy,
• Middle cerebellar
peduncle lesions.
• Intranuclear
inclusions
• Peripheral
neuropathy,
• Autonomic
dysfunction
Clinical features
of FXTAS include:
• Cerebellar
ataxia,
• Dementia,
• Anxiety,
Irritability,
Depression,
• Incontinence,
• Impotence,
30. Fragile X-associated
Primary Ovarian Insufficiency :
Reported in 20-25% of women
with permutations;
30-fold increase compared with
the general population.
Women with a diagnosis of
ovarian insufficiency: 2-15% have
a permutation of FXS.
Directly related to the number of
CGG repeats:
◦ Premature ovarian failure
◦ Early menopause
◦ Irregular menses,
◦ Decreased fertility,
◦ Elevated FSH
33. Genetic Tests
Specific Chromosome Disorder:
◦ karyotyping / Chromosome analysis.
Specific genetic disorder:
◦ Diagnosis:
PCR or Southern Blot Analysis.
FISH: labels the gene on the chromosome.
◦ Screening:
Immunocytochemical testing e.g. Willemsen
Antibody Test.
The Rapid PCR-Based Screening test
No specific genetic disorder:
◦ Microarray Comparative Genomic
Hybridization (aCGH) Testing.
34. FXS: Screening Tests
Sabaratnam & Thakker, 2003; Medscape reference 2013
Polymerase Chain Reaction (PCR):
Is the routine screening test used on FXS.
Faster, less expensive & requires a minimal
sample,
Effective for small premutations but not very
sensitive in full mutations.
The Rapid PCR-Based Screening test (Blood
Spot Test ) (Tassone et al, 2008):
Both males and females
55 to 200 CGG repeats & full-mutation ranges.
Rapid detection using even 1% of the DNA from
a single dried blood spot.
Screening large populations.
Costs $5 : $1 per sample.
Flora Tassone
42. In the normal state:
• mGluR activation by glutamate (glu) results in
activation of dendritic translation through the
phospholipase C (PL-C) cascade.
• FMRP levels increase with translational
activation, and FMRP then inhibits translation,
acting as the negative feedback or “brake” on
the translational mechanism.
43. When FMRP is missing in FXS:
• mGluR-mediated translation lacks the negative
feedback balance > excessive:
• Synthesis of specific synaptic proteins,
• Internalization of AMPA receptors,
• Other synaptic changes
• > Excessive long-term depression.
• > persistently weak and immature synapses.
44. • MPEP & other mGluR5 –ve modulator > blocks mGluR-mediated
LTD
• Lithium: blocks inositol phosphate (IP) turnover, and blocking PL-C
mediated signal transduction, also inhibits GSK3β activity > block in
part excessively activated mGluR-mediated translation.
• CX516 or other Ampakines: increases AMPA activity directly &
redistributes AMPA receptors to the synaptic membrane through
activation of BDNF.
45. Fenobam mGluR5 antagonist Open-label, single-dose trial in 12 adults.
AFQ056 mGluR5 antagonist Phase II trials in adults and adolescents and Phase
I trials in children underway
Acamprosate Probable mGluR5 antagonist, Open-label study in 3 adult males.
Phase III trial in children underway
RO4917523 mGluR5 antagonist Phase II trials in adult males underway
STX107 mGluR5 antagonist Phase II trials in adult males in development
Riluzole believed to block presynaptic
glutamate release.
Open-label study in 6 adult males:
Memantine NMDA antagonist Chart review of 6 young adults treated
Minocycline MMP-9 inhibitor Phase II trials in children recently completed.
Lithium GSK3 inhibitor; increases BDNF
production
Open-label study in 15 children and adults:
Arbaclofen GABABR agonist Phase II randomized, placebo-controlled trial in 63
children and adults: Phase III trials in children and
adults underway
CX516 Positive modulation of AMPA
receptors
Randomized, placebo-controlled trials in 49 adults:
OT Neuropeptide involved in pro-
social behaviour
Randomized, placebo-controlled trial in 10 young
adult males:
Donepezil Acetylcholinesterase antagonist Open-label trial in 9 adults. Randomized controlled
trial in young adults underway
46. • In mice (& other animals) with FXS, data supporting the
mGluR theory and drugs that correct mGluR overexpression
are robust, with many studies reporting phenotypic ‘rescue'
and behaviour that is indiscernible from WT).
Drug Trials: Conclusion
Politte et al, 2013
47. In human trials: Not the same
• Results of targeted treatment trials have
been encouraging but not striking.
• Treatment improves behaviours; do not
reverse physical phenotype.
• Trials > increased methodological
difficulties > significant potential for bias
In animals:
• Both reduced and enhanced NMDAR
functioning > ASD in mice.
Why:
• Biological differences.
• More complex model: FXS > diverse
symptoms, LD, ASD, ADHD (??).
FXS Drug Trials: Conclusion
Politte et al, 2013
48. • Most favourable outcomes would be
obtained with early childhood
intervention,
• The choice of target population in
future clinical trials should be
carefully considered.
• Number of CGG repeats
• Extent of methylation
• Associated pathology
• Stage of development
• Still many other potential therapies
are to be discovered
Drug Trials: Conclusion
Politte et al, 2013
51. Screening for FXS:
• Many FXS > late diagnoses > missing
the critical period.
• 50% of parents > another child or
pregnancy before diagnosis.
• Testing for FXS is recommended for
FXS families and high risk groups:
• Features of FXS and LD.
• LD.
• Autism.
• Women with primary ovarian
insufficiency.
• Aging adults with ataxia or tremor
combined with other features of FXTAS.
• Family history consistent with FXS.
52. • New-born screening for
FXS > currently
researched in USA.
• Less-expensive screening
methods have been
developed > Blood Spot
Test (Tassone et al, 2008):
less than $5 / test > full
mutation & premutation.
• If positive > further tests
e.g. PCR or Southern
Blotting.
Screening for FXS:
53. • Risk for FXS > testing of the individual
then family.
• Referral to a geneticist and/or genetic
counselling:
• Identify individuals at risk
• Help with how information is
conveyed to family members.
• review reproductive options for
future pregnancies, including egg
donation, prenatal diagnosis,
adoption, and pre-implantation
genetic diagnosis through polar
body analysis.
• Help to be connected to support
groups.
Genetic Counselling
(Hagerman et al, 2009)
54.
55.
56. Educational Services
(Hagerman et al, 2009)
•Research > educational services,
have been associated with better
behavioural outcomes and fewer
autistic behaviours.
•Hagerman: “I can make an FXS
child able to learn but I can not
teach him”.
•MIND institute > New video
games style educational
programmes.
•Learning skills > information.
57. Current research > IQ, symptoms and
functioning of FXS patients improve
with positive elements in:
• Environment.
• Stress management interventions.
• Sensory processing interventions.
• Behavioural intervention teams /
programmes.
• Psychotherapy or Counselling.
• Speech therapy.
• Cognitive behavioural Therapy.
• Social Skills-Oriented Group
Therapy.
REHABILITATIVE
INTERVENTIONS
(Hagerman et al, 2009)