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--z2394943 10:57, 20 October 2011 (EST)

Online Assessment


1. Identify the origin of In Vitro Fertilization and the 2010 nobel prize winner associated with this technique.

In 1978, Louise Brown, the first IVF baby was born. In Vitro Fertilisation (IVF) aids couples who may have trouble conceiving or are considered infertile. IVF involves the extraction of both the oocyte (female egg) and spermatozoa (male sperm) with fertilisation occurring outside the human body in a glass dish. Once fertilisation has occurred the zygote is then implanted back in to the female uterus. The idea of human IVF started in the mid 20th century by Robert G. Edwards who had studied fertilisation for many years and in 2010 Edwards was awarded the nobel prize in physiology or medicine. [1]

2. Identify a recent paper on fertilisation and describe its key findings.

McAvey B Zapantis, A, Jindal SK, Lieman HJ, Polotsky AJ. (2011 ) How many eggs are needed to produce an assisted reproductive technology baby: is more always better? Fertility Sterility. 96(2):332-5. [2] This paper looked at the optimum number of oocytes that could be used in IVF to give the highest chance of live birth. They found 6-9 oocytes was advantageous in comparison to 5 or less oocytes, as well as, 10 or more oocytes. Thus suggesting more is not always better. This may aid future IVF patients not having to receive multiple treatments.

3. Identify 2 congenital anomalies.

Congenital Anomalies are considered to be defects and/or disorders present at birth, such as Achondroplasia & Polydactyly.

--Mark Hill 00:43, 30 July 2011 (EST) Good the citation should be PMID:21718991 or I will show in lab how to generate a reference list.


1. Identify the ZP protein that spermatozoa binds and how is this changed (altered) after fertilisation.

There are four Zona Pellucida (ZP) proteins within a human ZP1, ZP2, ZP3, ZP4. Before fertilization can occur the spermatozoa must undergo capacitation within the female uterus, in which the glycoprotein coat is detached from the spermatozoa's arcosomal surface. The zona pellucida surrounding the oocyte contains a glycoprotein ZP3, which acts as a receptor for the acrosome of the spermatozoa. Many spermatozoa release the contents of the acrosome, which lyse and degraded the zona pellucida thus exposing the surface of the oocyte to spermatozoa allowing it to bind to ZP2. The remaining zona pellucida undergoes a cortical reaction in which it increases the intracellular calcium levels causing depolarisation. This process allows the zona pellucida to become impermeable to other spermatozoa preventing polyspermy. ZP3 does undergo some changes after the cortical reaction it loses 1. its sperm binding ability 2. the capacity to promote the release of the spermatozoa's acrosome. [1] Occuring next would be the membrane fusion of the oocyte and spermatozoa.

2. Identify a review and a research article related to your group topic. (Paste on both group discussion page with signature and on your own page)

  • Review article PMID:11834588 This review looks at many different aspects of DMD and highlights how the lack of the gene dystrophin effects the brain, which may result in cognitive difficulties.
  • Research article PMID:20139167 This research article explores how branching of skeletal muscle causes weakness in the cyclic nature of regeneration and degredation in DMD.


  1. <pubmed>10341000</pubmed>


1. What is the maternal dietary requirement for late neural development?

Iodine is a maternal dietary requirement for neural development with studies showing that it is a key source in providing thyroid associated hormones (T4) to the embryo before the thyroid of the foetus can take over. [1] If pregnant women become iodine deficient the foetus can suffer from hypothyroidism, goitres and abnormalities can arise, such as endemic cretinism. [2]

2. Upload a picture relating to your group project

Oxidative Stress Response in Friedreich Ataxia.jpg

  • Oxidative Stress Response in Friedreich Ataxia
Differentially expressed RefSeq genes in human trisomy 21

--Mark Hill 15:30, 14 August 2011 (EST) This part is fine. I will be giving a tutorial in next week's lab to fix the referencing.


  1. <pubmed>7750195</pubmed>
  2. <pubmed>7984194</pubmed>


1. The allantois, identified in the placental cord, is continuous with what anatomical structure?

The allantois in early embryonic life is an out-pouching of the hind gut and enters the connecting stalk. In later development the allantois becomes continuous with the developing superior urinary bladder and runs into the umbilicus. Though it is not a functional structure, the remnant can be seen in adults as the urachus, which extends from the apex of the bladder to the umbilicus creating the median umbilical ligament under the median periumbilical fold.

2. Identify the 3 vascular shunts, and their location, in the embryonic circulation.

  • Foramen Ovale: blood passes between the right to left atria
  • Ductus Arteriosus: blood passes between the pulmonary trunk to the aorta
  • Ductus Venosus: blood passes between umbilical vein to the inferior vena cava.

3. Identify the Group project sub-section that you will be researching.

Introduction (history, epidemiology, age, gender, race) & Neuropathology --z3294943 09:50, 24 August 2011 (EST)


1. Which side (L/R) is most common for diaphragmatic hernia and why?

Congenital diaphragmatic hernia's (CDH) occur more commonly on the left side, approximately 90% of the time, more specifaclly at the foramen of Bochdalek. The posterolateral defect is due to incomplete fusion or abnormal formation of the pleuroperitoneal membranes. Reason as to why the left side is more commonly susceptible to CDH may be due to the fact that the right pleuroperitoneal membranes fuse much earlier then the left. --z3294943 17:00, 29 August 2011 (EST)


1. What week of development do the palatal shelves fuse?

Palatogenesis occurs in two stages, primary and secondary palate development. During primary palatal development the embryonic palatal shelves are formed from mesenchyme of the medial nasal prominences and it continues to form the midline of the anterior maxilla. Secondary palatal fusion occurs in week 9 of a human embryonic development forming the hard and soft palates, which separate the nasal and oral cavities.

2. What animal model helped elucidate the neural crest origin and migration of cells?

The chicken embryo provided visible migration of neural crest cells due to a Dil-label. The chick-quail chimera also provided great insight into the origin of neural crest cells. Nicole Le Douarin discovered that if a segment of neural tube and neural crest cells of a quail are implanted into a chick (at the the same embryonic stage) it is easy to observe the origin and migration of the neural crest cells.

3. What abnormality results from neural crest not migrating into the cardiac outflow tract?

Neural crest cells contribute to the cardiac outflow tract, namely the aorta and pulmonary trunk, and are very important for cardiogenesis. If migration of these cells does not occur truncation and malformation of the aorticopulmonary septum can eventuate. This will lead to an aorticopulmonary septal defect in which there is communication between the aorta and pulmonary trunk via small aortic window. Furthermore, Tetralogy of Fallot is believed to arise from abnormal and/or absent cardiac neural crest migration. --z3294943 17:20, 11 September 2011 (EST)


1. Are satellite cells (a) necessary for muscle hypertrophy and (b) generally involved in hypertrophy?

a) It has been shown that satellite cells are not necessary for muscle hypertrophy.

b) However, satellite cells will proliferate and differentiate during hypertrophy.

2. Why does chronic low frequency stimulation cause a fast to slow fibre type shift?

Impulse activity is a determinant of fast and slow muscle fibre types. When chronic low frequency stimulation (CLFS) occurs on the nerves of fast muscle it can cause a phenotypical shift of the fast fibre type to a slow fibre type. [1] As slow type fibres generally make up the bulk of postural muscles, such as the erector spinae, they are receive low frequency stimulation to remain "switched on". So when fast muscle fibre type receive CLFS there a transition in the contractile properties of the muscle, namely myosin heavy chains, as well as the histochemical properties from a fast to a slow phenotype. [2]

3. Peer Review Trisomy 21

The overview: Good use of headings, structure seems to be a little mixed. Maybe start with board heading the subdheadings to beak up the writing and make it easy to understand. Illustration and text ratio was nice not to heavy on either. No student drawing. Would have been nice to add a genetics heading rather then just linking to different pages. This looks strange at the top.. maybe rethink position. Trisomy Karyotypes could have been added here.

  • some words are not included in glossary eg AMH acronyms must be explained
  • some pictures seem to be muddle eg the picture of Down himself would have fit nicely in the intro..
  • many aspects of the page are not cited. This would give you page more credibility.


  • the first sentence is a little to word, as introduction should be punchy and to the point. Maybe try and re-word

Down syndrome or trisomy 21 is caused by nondisjunction of chromosome 21 in a parent who is chromosomally normal and is one of the most common chromosomal abnormalities in liveborn children.

Maybe.. The most common chromosomal abnormality occurring in live births is Down syndrome, otherwise known as Trisomy 21. This syndrome is caused by the nondisjustion of the 21st chromosome, in which there is the partial or whole presence of an extra chromosome.

  • The history of Down syndrome would be a nice extra such as when the chromosome was identified.

Also rewording of the sentence Down Syndrome is the historic name used for this condition identified by Down, J.L.H. in a 1866 paper where he described the "phenotypic features that includes mental retardation and characteristic facies".

Such as, In 1866 John Langdon Down identified and described some of his patients who he said to have "phenotypic features that includes mental retardation and characteristic facies". Due to his historic findings this syndrome now bares Downs’ name. Reference?

Recent Findings • In recent findings it might be nice to summaries the paper rather then quote directly from it. Some thing are difficult to understand and I don’t quite get the gist of what is actually being done. • I like the link to PubMed- great thinking. Associated Congenital Abnormalities • good use of bullet point maybe have been nice to illustrate abnormalities with pictures.

Heart Defects I like the of percentages but where were these numbers generated from? No reference?? Good use of links here.

Limb Defects could have had major head “defects” then use subheading to differentiate limb and heart. )

  • The use of references such accompany statistics.

American College of Obstetricians and Gynecologists Recommendations • interesting choice, would have been nice to see in own words not just copy and pasted. Prevalence • May fit in nicer near the intro, as readers are generally very interested in this part. • Good to see the use of references Down's syndrome Screening • Maybe nice to re word.. Screening Strategies for Down’s Syndrome. • Great use of table and stats. • Sentence There are several additional suggested screening stratagies currently at various stages of development. These techniques should be seen as at the research stage only until data, a clinical concensus and a recommendation has been made. Consider rewording as it is a little hard to read Spelling errors 1. Strategies 2. Consensus

  • Detection using Tandem Single Nucleotide Polymorphisms image. Consider resizing as it is very large.

Trisomy 21 Growth Charts

  • describing in own words would be ice rather then copy and paste.


  1. <pubmed>1295870</pubmed>
  2. <pubmed>12500901</pubmed>

--z3294943 20:20, 16 September 2011 (EST)


Peer Review

Group 1

  • Good overall structure with headings and subheadings, it breaks up the text and makes it easy to follow.
  • Very interesting topic with a lot of good relevant information.
  • Pictures and tables are great. Just make sure your pictures are referenced properly eg. karyotype picture. also it might make the page look cleaner if the pictures are either all on the left or all on the right. this also may avoid the headings being shifted.
  • Maternal Serum Sampling, very nicely drawn, could you maybe label the picture as to what everything is so the reader can identify the structures easily.
  • Might be nice to add in a history timeline.
  • maybe you could use sub headings in the aetiology section.
  • Clinical manifestations had good use of subheading and collated information. I like the simplicity of dot points... could you maybe add a picture here to break up the text and keep the reader engaged.
  • Make sure your references aren't doubled.

Group 2

  • Structure- headings, subheadings and tables make this a very readable page with a nice flow.
  • It may be nice to have the colours of the tables continuous throughout the page. eg only yellow.
  • Ensure all your pictures are correctly referenced, it would be a shame if Mark deleted them, as they add a lot to your page and aid in read ability.
  • not to text heavy which is good!
  • Intro well written an gives a good scope to the syndrome.
  • Dianostic Tests: I like this section and that the images accompany the text.
  • Tetralogy of fallot as on example of the congenital heart defects that can occur in DiGeorge syndrome: Very interesting example, great pictures!! very well drawn. maybe you could put the pictures vertically down the page.
  • Current and Future Research section it might be nice to add subheadings of what the research is.
  • Good use of citing/ referencing it gives your page authority/ believability, just beware of the doubling in your reference list.
  • It might nice to collate all the genetic info into one section.

Group 3

  • Good over all structure with the use of headings and sub headings. A very interesting syndrome and the page is easy to read.
  • I think the intro could be condensed a little, as it should get straight to the point.
  • I enjoyed reading the history section and good use of table and summary of history.
  • I like figure 1, very nice that it was done by a student!
  • figure 4 Maternal Non-Disjunction.. Is this a student drawn pic or did you use it from somewhere.. a little unclear.
  • I was nice to see sign and symptoms tabulated, which made this section very easy to read and understand. good use of picture here. Could you find anymore relating to the signs and symptoms?
  • I liked the addition of a movie link.
  • The sub heading of diagnosis were very appropriate.
  • Other Similar Defects- very interesting to add this in..
  • Interesting current research: nice that it has been summarised.
  • Make sure your reference list hasn't doubled up.
  • Just for clarity it might be nice to use the same colour table throughout the page.
  • It was good to see some of your pictures correctly labelled.

Group 4

  • Nice structure of headings and subheadings, it breaks up the text and makes it a readable page. Extremely interesting topic!
  • I found the history very interesting and enjoyed the quote from Huntington.
  • maybe bold the dates in the timeline, just to make the page easy to follow. Or maybe a table could be appropriate.
  • I liked the structure of the epidemiology section and the tabulated prevalences! good work!
  • Molecular Mechanisms & Pathogenesis: unsure as to why some sentences were bolded.
  • Differential Diagnosis: very interesting I liked that you added this in.
  • Treatments table very succinct easy to understand and follow! Great!
  • Good to see that most of your references were grouped. only a few that were doubled.
  • Maybe have a continuos colour scheme for the page and type of table used.
  • Good use of tables and I like that you explained what they were about.
  • Make sure all acronyms and scientific language is in the glossary
  • good student illustrations
  • overall great ratio of text and pictures!

Group 5

  • Great structure with headings and subheadings, very easy to follow and read.
  • Nice succinct intro. good over view of the disease. - Maybe you could dot point phenotypic abnormalities
  • Some areas a little text heavy, additional pictures would fix this problem. for example some more pictures in signs and symptoms.
  • Good simple history, well researched. easy to follow.
  • Maybe Screening/Population testing could be its own heading.
  • Great section on development of disease! I like the format very interesting relevant information! well done!
  • Treatment section well put together but a little text heavy- try condensing info or bullet points.
  • Make sure all the pictures are referenced properly.
  • Nice to see your references grouped.
  • NIce student drawn picture.
  • Make sure all your acronyms/ scientific lingo is in the glossary.
  • I liked that you has a continuous colour scheme for your tables. It makes your page look very neat.
  • The bottom of the page is a little text heavy.

Group 6

  • Nice overall structure and good use of headings and subheading. It gives the page a nice flow.
  • INtroduction is nice and straight to the point and gives the reader a good overview of your topic.
  • I like the historical section with interesting subheadings used, maybe you could add a timeline just to simplify the info.
  • Signs and symptoms nicely arranged. could you add some more pictures here?
  • Pathophysiology and Abnormalities section need to have the references accompanying the information. Just so the read can identify where all the info is from.
  • The diagnostic tests table would be nice with some colour and when the images are it will look complete. It's a little text heavy for a table maybe try bullet points. also the referencing system has changed in this table? and a little unsure of the reference at the bottom of the section?
  • Treatment/Management section is nicely arranged.. could you add another picture here just to compensate for the amount of text. the table really brightens up the page!
  • Future directions section is nicely summarised and I like the tone of voice used here. just make sure the referencing is correct as it is a little confusing and interrupts the flow of the section.
  • Maybe the use of similar tables and colour scheme will increase the continuity of the page.
  • Make sure your references are not doubled in the list.
  • Ensure all of your pictures are correctly referenced.
  • Make sure all acronyms and scientific wording is in the glossary.

Group 7

  • Good use of headings, maybe you could add sub headings into beak up the text and make the page easy to follow.
  • Intro section- maybe you could dot point the clinical features to make it easier to read.
  • Some of your intro and history dates dont correlate but this might be a typing mistake? 1956 and 1965??
  • Nice use of time line.
  • The epidemiology looks a little bare. Is there anymore info that could be added.
  • In the aetiology table make sure all your stats are referenced.
  • UBE3A Ubiquitylation Pathway picture is extremely large, maybe you could resize this.
  • I like the addition of animal models. With an amazing picture!
  • Sings and symptoms section is very well put together structurally- good use of subheadings, pictures and tables.
  • Are there anymore complication you could add for AS?
  • Maybe you could tabulate your diagnosis section. I like the flow chart!
  • Could have a common heading Related syndromes and differential diagnosis then use subheadings to split them up.
  • Genetic Counselling unsure of what this section is and what the table relates to?
  • I like that you colour scheme/tables are continuous through out the page.
  • Just make sure you reference list isn't doubled for some references.
  • make sure all acronyms are added to the glossary.
  • Nice student illustrations.

Group 9

  • The structure and use of headings and subheadings is good but i think you need to rethink the order of your headings eg epidemiology should be closer to the beginning.
  • Intro informative. maybe you could bullet point the phenotypic characteristics, just make it easier to read. could you add a picture in this section?
  • Nice history, could you maybe put your timeline into a table.
  • good use of the table in genetics and aetiology and nice to see the accompanying picture referenced.
  • I feel treatment should be its own heading and not a subheading.
  • Phenotype of Williams Syndrome- a nice easy to read section breaking up the text. Could you add anymore pictures here?
  • Genitourinary Conditions is very text heavy could you add in some pictures here or tabulate some of the information, just to keep the page flowing nicely.
  • The endocrine section should be renamed, as it does not really explain to the reader what your going to talk about.
  • Other Associated Medical Conditions- is a nice section good use of the table.
  • Cognitive, Behavioural and Neurological Phenotype section is very text heavy it needs to be broken up either by pictures or a table. but it seems like a lot of effort has been put into the research in this section.
  • Im not sure whether this section is necessary for our assessment Specialised Facilities and Supportive Associations??
  • Current research and developments should be above the preceding section and a summary of the information would be nice instead of dot points.

Group 10

  • The structure and use of headings and subheadings is good.
  • Good info very informative and it gives a good overview to DMD.
  • HIstory has a lot of text could you use a timeline here?
  • i think a picture of the pathogenesis would improve this section.
  • Has your group look at the CNS and cognitive function of DMD boys its a controversial area as many people have different attitudes towards this but Dr Stewart Head a UNSW lecture actually studies DMD and is very informative in the area and recently published a article in the journal Brain.
  • The CNS is highly affected by the lack of dystrophin as well as GABA receptors. I think this area is very import to consider as it highly affects the boys at school.
  • Could you add some pictures to your page or break it up with the use of more tables as it a lot of text in comparison to pictures and tables.
  • Make sure your reference list is not doubled.
  • Ensure all your pictures are referenced properly.
  • Student image is present.

Group 11

  • Interesting topic with good use of pictures, you guys have a great topic with a lot of interesting areas to discuss.
  • The headings could be reorganised for example diagnosis could come after explaining in detail what cleft lips are and how they are formed embryonically.
  • The introduction should introduce the main topics that you will be discussing but only briefly like what cleft palate is.. the information in the intro would fit nicely in epidemiology. (maybe you could add this section in).
  • History section is very interesting I liked the extra research.
  • The time line takes up a lot of room maybe condense it into a table format.
  • Development?? is this a section??
  • maybe put the type of cleft lip/palate into a table with a pictures corresponding to the specific type.
  • Make sure all acronyms are in the glossary.
  • It would be nice if the colours of the tables were continuous throughout the page.
  • Neuroembryology and functional anatomy of craniofacial clefts section is very well written and enjoyable to read.
  • Treatment & Problems associated with Cleft Palate sections have no referencing. It would strengthen and give your page some authority if you cited where your information was from.
  • A little summary for your future and current research would make this section a bit more interesting rather then just using dot points.
  • Make sure your references aren't doubled.
  • Ensure your pictures are referenced correctly.
  • Furlow Z-plasty technique picture is positioned so that it interrupts the flow of reading maybe rethink the position of this picture.
  • Variations of Cleft Lip or Palate picture is great and I think it could be more of a "key " picture on your page maybe centralise it?.
  • No student drawing.
  • Gallery seems a little irrelevant.
  • More needs to be added into glossary eg. Otitis media

--z3294943 15:28, 24 September 2011 (EST)

LAB 10

1. Besides fetal alcohol syndrome, identify another environmental teratogen that can lead to hearing loss.

There are many environmental teratogens that can cause congenital hearing loss such examples include viruses Rubella [1] and Cytomegalovirus. [2]

2. Identify 3 factors that contribute to poor neonatal drainage of the middle ear. The factors contributing to middle ear infections in the neonate revolve around the auditory tube and include:

  1. The angle of the neonate auditory tube lies more horizontal on a 10 degree angle and the adult auditory tube is more diagonal and lies on a 45 degree angle, which aids in drainage of this middle ear.
  2. The musculature involved with the middle ear in the neonate includes only one muscle- tensor palati where as the adult has two muscles involved tensor palati and levator palati.
  3. The size of auditory tube also changes considerably the neonatal tube is very narrow and short, in comparison to the adult tube which is longer and wide.

3. Identify 1 genetic abnormality that affects hearing development and link to the OMIM record.

PENDRED SYNDROME (PDS) Is an autosomal recessive disorder involving thyroid enlargement as well as abnormal cochlea development and sensorineural hearing loss.



  1. <pubmed>20151880</pubmed>
  2. <pubmed>21648339</pubmed>

--z3294943 19:48, 6 October 2011 (EST)

LAB 11

1. Name the components that give rise to the interatrial septum and the passages that connect the right and left atria.

The interatrial septum begins dividing the atria in week 4/5 of embryonic development. Firstly, the septum primum arises from the roof of the myocardium making its way down toward the endocardial cushion. A communication is left between septum primum and the endocardial cushion, known as the foramen primum. Immediately to the right of the septum primum a second septum arises from the myocardium known as septum secundum, which is strong and muscular and grows over foramen primum. Apoptosis of septum primum leaves a second communication in the atria known as the foramen secundum. Septum secundum also leaves a communication, foramen ovale, between the left and right atria, which acts as shunt for blood.

2. Identify the cardiac defects that arise through abnormal development of the outflow tract.

  • Transposition of the great vessels
  • Ventricular septal defect and aorticopulmonary septal defect
  • Stenosis of the aortic valve with can lead to hypertrophy of the left ventricle
  • Double outlet of the right ventricle

--z3294943 1:12 14th October 2011 (EST)

LAB 12

1. Give examples of 3 systems that continue to develop.

  • Respiratory System
  • Musculoskeletal System
  • Neural development postnatally

2. Identify the abnormalities detected by the Guthrie Test and link to one abnormality listed in OMIM.

The Guthrie test is able to identify specific abnormalities via a simple blood test, such abnormalities include:

  • Cystic Fibrosis (CF) (OMIM CYSTIC FIBROSIS)
  • Phenylketonuria (PKU)
  • Hypothyroidism
  • Galatosaemia
  • Homocystinuria
  • Congenital Adrenal Hyperplasia
  • Toxoplasmosis

--z3294943 3:15 20 October 2011 (EST)

Project stuff

Date Significance
1863 Friedreich describes the clinical presentation of patients and publishes his findings. [1]
1882 Brousse et al suggests that many diseases have been mistaken for FRDA, such as Charcot-Marie-Tooth disease or syphilis, which called for further investigation and classification techniques for FRDA [2]
1907 A study by Mott et al gave the first detailed description of the dentate nucleus and the role it plays in FRDA pathology. [3]
1976 The Québec Collaborative Group proposed a systematic way of classifying and diagnosing FRDA, such as the absence of tendon reflexes. [4]
1980 FRDA patients were found to have iron-positive granules deposited within cardiomyocytes, as well as, skeletal muscle fibres. [5]
1988 The chromosomal locus for Friedreich’s ataxia was mapped to chromosome 9q13. [6] [1]
1989 Wallis et al developed the first prenatal diagnostic test for FRDA via DNA markers. [7]
1990 Two closer DNA markers were establish by Hanauer et al improving prenatal test to almost 99%. [8]
1995 Monros et al refined prenatal testing in regards to new recombination techniques available with an accuracy close to 100%. [9]
1996 Frataxin, the mutated gene responsible for FRDA, was discovered by Campuzano et al, which allowed for molecular testing and full clinical classification of the disease. [10] [6]
1997 Rötig et al reported on the defective activity of the iron-sulphur clusters in FRDA patients, in relation to mitochondrial respiratory complexes I, II and III via a yeast homologue. They also discovered the protein aconitase to also be deficient with in patients, thus suggesting that iron accumulation is a key component in FRDA pathogenesis. [11]
Whilst researching the GAA trinucleotide repeat expansion Cossée et al uncovered that nearly 17% of expansions consisted of repeats longer than 16 GAA. [12]
2002 Mühlenhoff et al demonstrated, via a yeast frataxin homologue (YFH1), that the decreased maturation of iron-sulphur proteins and accumulation of mitochondrial iron are critical factors in oxidative stress in FRDA. [13]
Current Research is looking into treatments for FRDA and Idebnone, which may reverse the redox reaction associated with FRDA looks very promising. [14]


It has been noted that FRDA has a range of prevalence’s in accordance to the country of interest. Caucasian populations have a higher prevalence of FRDA with approximate carrier frequencies varying between 1:50 to 1:100. [3] This includes Australia, the United States of America and similar European countries, which have the aforementioned prevalence of 1 in 50,000. [15]

Studies performed in Italy revealed an extremely high birth incidence of FRDA with the disease affecting 4.9 in every 50,000 live births. [16]

Some Southern and Central American countries, such as Cuba, have a much lower prevalence of FRDA approximately 1 in 2,200,00 in addition to lower carrier frequencies of 1:745. [17] FRDA also has a high prevalence in North Africa, the Middle East and India.

Furthermore, Asian, sub-Saharan African and Amerindian populations have a much lower prevalence or the FDRA genetic mutation is non existent. [3] [2] [16]

Spinal Cord Schematic

This schematic diagram of the human spinal cord highlights the major areas affected by the pathogenesis of FRDA. The dorsal root ganglion and dorsal roots undergo excessive demyelination and are considered the primary neurodegenerative lesions of FRDA. Furthermore, note the dorsal nuclei of Clarke, spinocerebellar tracts and corticospinal tract, which endure secondary lesions in FRDA.

"Beginning six months after publication, I (z3294943) grant the public the non-exclusive right to copy, distribute, or display the Work under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported license, as described at and"

Internal Link

Neural - Cerebellum Development

  1. 1.0 1.1 <pubmed>15090560</pubmed>
  2. 2.0 2.1 <pubmed>10633128</pubmed>
  3. 3.0 3.1 3.2 <pubmed>21315377</pubmed>
  4. <pubmed>20156111 </pubmed>
  5. <pubmed>6452194</pubmed>
  6. 6.0 6.1 <pubmed>10607838</pubmed>
  7. <pubmed>2574535</pubmed>
  8. <pubmed>1970404</pubmed>
  9. <pubmed>7659688</pubmed>
  10. <pubmed>19283344</pubmed>
  11. <pubmed>9326946</pubmed>
  12. <pubmed>9207112</pubmed>
  13. <pubmed>12165564</pubmed>
  14. <pubmed>19283347</pubmed>
  15. <pubmed>20374234</pubmed>
  16. 16.0 16.1 <pubmed>14767759</pubmed>
  17. <pubmed>20569261</pubmed>