Advanced Cell Biology 2022-23: Coursework 3

Topic: Genome Editing

Aim: To demonstrate an ability to explain scientific research to a non-specialist

audience. This is a key skill for all scientists and helps clarify our thinking about what is

most important about a particular piece of work. Most funding applications for research

require a lay summary, and this is considered an essential part of public engagement

and scientific accountability. Similarly, many jobs in science involve communication of

complex data to non-specialist audiences such as the general public, shareholders, or

politicians.

For a wider context, see also: https://www.nature.com/articles/d41586-020-00580-w

The Task: Write a lay summary of not more than 250 words explaining the research

described in the technical abstract below from a controversial scientific paper about

genome editing in human embryos. Use the example from class to guide you in

structuring the summary. You will be introduced to the scientific concepts described in

the abstract in the Genome Editing lectures on the ACB course.

For this coursework, your target reader is an engaged year 11 school student (~age 16).

This coursework should be submitted in electronic format using Moodle by midnight on

27th January 2023. You must express the summary in your own words - text transcribed

from other sources will be excluded from marking. Please include your student number

at the start of your document.

Correction of a pathogenic gene mutation in human embryos

ABSTRACT

Genome editing has potential for the targeted correction of germline mutations.

Here we describe the correction of the heterozygous MYBPC3 mutation in human

preimplantation embryos with precise CRISPR-Cas9-based targeting accuracy

and high homology-directed repair efficiency by activating an endogenous,

germline-specific DNA repair response. Induced double-strand breaks (DSBs) at

the mutant paternal allele were predominantly repaired using the homologous

wild-type maternal gene instead of a synthetic DNA template. By modulating the

cell cycle stage at which the DSB was induced, we were able to avoid mosaicism

in cleaving embryos and achieve a high yield of homozygous embryos carrying

the wild-type MYBPC3 gene without evidence of off-target mutations. The

efficiency, accuracy and safety of the approach presented suggest that it has

potential to be used for the correction of heritable mutations in human embryos

by complementing preimplantation genetic diagnosis. However, much remains to

be considered before clinical applications, including the reproducibility of the

technique with other heterozygous mutations.

Nature. 2017 Aug 24;548(7668):413-419. https://www.nature.com/articles/nature23305 Further reading

Some of the interpretations in this paper have been questioned by other researchers.

Their views are published as Brief Communications Arising in the same journal:

https://www.nature.com/articles/s41586-018-0380-z

https://www.nature.com/articles/s41586-018-0379-5

The authors of the original study then had the chance to reply:

https://www.nature.com/articles/s41586-018-0381-y

Reading these associated articles will give a broader perspective on the original study.

Plagiarism statement

Digital submission of your answer file is equivalent to your explicit declaration that you

have adhered to our community expectations of academic integrity and that the work

submitted is entirely your own. Answer files will be checked with software designed to

detect plagiarism. Answers comprised mainly of text simply copied directly from learning

materials will reveal little understanding by the student and hence cannot score highly.

Further: markers will be looking for unseemly degrees of similarity in the answers of

multiple students; such answers will attract no marks.

Assessment Criteria

See next page. Grade

(Degree Class)

A+

(1)

D

(1)

A-

(1)

B+

B

B-

(21)

C+

tu

(2ii)

D-

(3)

F

(Fail)

Numerical

Scale

98

95

92

88

85

82

78 75 72

68

65

62

58

55

52

48

45

40

Pass-Fail Boundary

38

30

20

10

Level 6 Assessment Criteria: ACB Coursework 3

O

CRITERIA

Exceptional. All the attributes of an A, plus: A highly sophisticated grasp of the topic,

with sufficient clarity and originality that the submission could be used without

editing for effective communication with non-scientists..

Outstanding. All the positive attributes of an A-, plus: further/deeper outside reading,

marshalled effectively in the submission. Minor defects in synthesis may be

compensated for by originality and clarity of presentation.

Excellent. Clear, complete and logical description of the topic. Appreciation of the wider

context underlying key concepts is evident, some of which may have been gained from

outside reading. Lucid and original communication of the topic is clearly demonstrated.

Very Good. The answer displays a very sound understanding of the main issues and

concepts, is generally well-organised, and the quality of writing and the language used

is overall very good. Lucid and original communication will be evident, but will be less

sophisticated than in a First Class answer. Some errors, minor omissions and/or partial

understanding of some aspects of the topic may be tolerated, so long as these do not

detract from an otherwise sound answer.

Good, but limited. The answer displays a reasonable understanding of the key issues and

concepts relevant to the topic, but may go little further than to reword, with little

evidence of insight or synthesis, information in the source material. Organisation of the

information is adequate for most of the answer. Errors, omissions, poorly expressed

ideas, and/or use of technical language -although none too serious-detract from the

overall quality.

Weak, but passable. The answer demonstrates a partial understanding of at least some

of the topic. Writing quality is adequate for at least part of the answer. However, the

answer is likely to be poorly organised and some of the basic requirements of the

question may not have been met. Errors, omissions, poorly expressed ideas using highly

technical language, and/or partial understanding will be too frequent/serious to merit a

higher grade.

Just passing. The answer must demonstrate a minimal understanding of the topic, but

coverage is only partial and superficial. The topic is covered by only the bare minimum

of required information, primarily in the form of minimal rephrasing of source material.

The minimum mark for a pass is 40%.

Borderline Fail. A serious attempt, but of insufficient quality to pass. A structured answer

is attempted, but it fails to demonstrate an adequate depth of knowledge and

understanding of the topic. This deficiency may be compounded by a disorganised

explanation and/or very poor or very technical language.

Minimum serious attempt. An attempt has been made to engage with the question, and

parts of the answer may have some merit, but there are major errors and/or omissions.

May also apply to an answer that is reasonably competent in parts, but for the most part

does not address the question set.

Clear Fail. A few relevant points show some engagement with the question, but these

are outweighed by severe errors and/or omissions.

An extremely brief answer, probably with only one or two key words or phrases of any

relevance to the subject addressed by the question.

Answer given has no merit, or answer is absent.