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Question 3 Short Answered Questions – (20%) Below is a pyrog…

Question 3 Short Answered Questions – (20%) Below is a pyrogram generated from analysis of DNA methylation of the NFATC1 gene promoter by pyrosequencing. Four CpG sites are indicated by grey bars. 3a) What is the DNA sequence? (2 marks) 3b) Is the region methylated or unmethylated in this sample? (2 marks) 3c) Explain how the incorporation of a nucleotide during pyrosequencing is used by an enzyme cascade to produce light. (3 marks) 3d) Explain why DNA is treated with sodium bisulfite for analysis of DNA methylation. (3 marks) — ESSAY QUESTION – (80%) Explain how DNA methylation and histone modifications regulate gene expression. In your answer, discuss how epigenetic modifications can enable monoallelic gene expression.

Question 2 Short Answered Questions – (20%) Below is the out…

Question 2 Short Answered Questions – (20%) Below is the output from analysis of the dystrophin (DMD) gene in a patient sample by multiplex ligation-dependent probe amplification (MLPA).   2a) What genetic abnormality has been identified in the patient sample? (2 marks) 2b) Why do MLPA probes contain a ‘stuffer’ sequence? (2 marks) 2c) The patient has no family history of muscular dystrophy. A blood sample from the patient’s mother was analysed and did not reveal any abnormality within the DMD gene. Explain the origins of the disease in the patient. (3 marks) 2d) A sample from a second patient revealed no insertions or deletions by MPLA. Explain why a diagnosis of Duchenne muscular dystrophy could not be excluded, and how diagnostic testing would proceed. (3 marks) — ESSAY QUESTION – 80% Explain the pathogenesis of the Duchenne and Becker muscular dystrophies. In your answer, critically evaluate exon skipping as a novel therapeutic approach for treating patients.

Question 1 Short Answered Questions – (20%) Below is an imag…

Question 1 Short Answered Questions – (20%) Below is an image from G-banding analysis of a sample from a leukaemia patient. Abnormalities have been indicated by arrows.                             1a) Using ISCN nomenclature, what is the karyotype of this individual? (2 marks) — Below is an image generated by fluorescence in situ hybridisation (FISH) for Patient A, who is a newborn child displaying low birth weight, microcephaly, poor lung function, and a weak cry. The probes map to the q arm of chr12 (green) and the p arm of chr18 (red).                         1b) What genetic abnormality is present in Patient A, and what diagnosis would be made? (2 marks) — Below is an image generated by fluorescence in situ hybridisation (FISH). The probes map to 22q11.2 (red) and a control probe mapping to 22q13.3 (green).   1c) What genetic abnormality is present in the individual? (2 marks) 1d) The affected region is approximately 3 mb in size. Explain why FISH was used rather than G-banding for this patient. (4 marks) — ESSAY QUESTION – (80%) Critically evaluate G-banding, fluorescence in situ hybridisation (FISH) and CGH arrays for the detection of cytogenetic abnormalities. For each technique, explain how specific disorders could be diagnosed.

There are FIVE questions from which you are required to answ…

There are FIVE questions from which you are required to answer only THREE; any additional answers will not be marked. All questions are comprised of an essay (80%) and short answered questions (20%), totalling 100% overall per question. Please refer to the steps below: Five text boxes are below this text box, one box for each question you can answer, each contains an essay question and short answered questions. Below the five question text boxes are 3 answer boxes where you will be answering the questions you wish to answer. Remember, you only need to answer THREE of the five available questions, which is why you have just 3 answer boxes. Within each answer box, please outline at the start which question/section you are answering to, and please label which part of the question you are answering, for example: ‘ I have chosen to answer all parts of Question 1: 1a) 1b) … Essay-  My answer to the Essay Question is: ‘