Medical genes and genomics
The task is designed to challenge you to apply basic concepts in genetics, and to make use of appropriate sources. Some of you will find that the recommended books contain useful material.
Other useful resources are; the Genetics section of MedlinePlus, which provides links to PubMed and Online Mendelian Inheritance in Man (OMIM). GeneCards is useful as is the Ensembl genome browser and the NCBI resources in general. However, some of this assignment requires the use of deduction and the answer(s) will not always be found by looking in textbooks or on the web.
Give a Uniform Resource Locator (URL) to the most relevant page for this condition in the Ensembl database.
Give information on the population frequency.
State the locus/loci of the major causative genetic change(s).
Give details of the precise cytogenetic or molecular abnormality, i.e. the nature of the genetic mutation(s) or anomaly(ies)
Give details of the inheritance pattern(s).
Note: If the condition that you have chosen to write about has multiple genetic causes / loci / modes of inheritance, please choose the most common one or two of each to describe.
Give an explanation for the mechanistic basis of the disorder (150 words maximum).
Note: It is recommended that you begin with the molecular biology, progress to the biochemistry and then to the physiology.
Give a brief account of symptoms, treatments and prognosis (150 words maximum).
NOTE: give your answer as one block of text of no more than 600 words, with bullet points a) – g). Your work must be fully referenced in the Harvard style and give a reference list at the end (this list and in-text citations are not included in the word count).
Produce a pedigree diagram to convey the information shown in italics below. Follow the conventions explained to you in teaching sessions and supplied as part of the learning material. Save your diagram as a picture file and upload it into the answer field in the blackboard test.
You may use the ‘Proband’ application to produce your pedigree, hand-draw it., or use any other suitable means. You may use any software or system that suits you, but keep the process simple to produce a neat, correct pedigree, swiftly. Take or save a picture of your work to upload.
David and Ali were married for 50 years, they retired to Spain, and spent 10 happy years there before Ali died following a bout of pneumonia. David died not long after, peacefully in his sleep. They had three daughters, the eldest married young and had one boy child who died in the 1980’s from HIV. He had contracted the virus from contaminated blood products used to treat his Haemophilia.
David and Ali’s second daughter, Mai-Moona had a son when she was 17 years old but would never reveal the identity of the father. She married some years later but divorced after only 10 months. She did not have any more children.
Mai-Moona’s son Jack is married and father to healthy identical twins. David and Ali’s youngest daughter never married her partner,
together they have three children, a boy, then a girl, then a boy. Their daughter, Amber is married to Craig.
Amber and Craig have two boys, Amber is pregnant with a girl at the moment. Their oldest child suffers from Haemophilia A, their second child has just been diagnosed with Prader-Willi syndrome.
3) Ali, from the ‘story’ in Q2 carried the haemophilia mutation. What was the percentage chance of it passing to Amber and Craig’s first-born child? Please give your answer as a PERCENTAGE TO ONE DECIMAL PLACE
4) Give and explain your working for the answer to question 3 AND discuss the chances of Amber and Craig’s unborn girl showing the Haemophilia phenotype (250 words MAXIMUM, please reference your answer)
5) MCQ: Which of the pedigree diagrams above is most likely to show a family with Haemophilia A?
6) MCQ: Which of the Pedigree diagrams above is most likely to show a family with Gaucher Disease
7) MCQ: Which of the Pedigree diagrams above is most likely to show a family with Galactosemia
8) MCQ: Which of the Pedigree Diagrams above is most likely to show a family with Hereditary haemorrhagic telangiectasia
9) MCQ: Which of the Pedigree Diagrams above is most likely to show a family with Becker muscular dystrophy
10) MCQ: What is the most likely inheritance pattern shown in Image D above?
11) Please explain your reasoning for the answers that you gave to questions 5-10. 250 words maximum.
