Question about Genetics (breast cancer):

I need help with genetics problem. I appreciate detailed descriptions!

Alice has come to you concerned that she might be at risk for breast cancer. Both her mother and her aunt have breast cancer and both have been discovered to be heterozygous for the same mutant allele of BRCA1, a small deletion that removes part of the coding region of the gene. Alice has had no tests, but wants to know what her chances are of developing breast cancer.

a. What test or tests would you recommend that Alice have done?

b. What results would you expect from these tests if Alice has this allele of BRCA1?

c. Explain to Alice (who is not a scientist) the results of the test and why they are convincing.

d. What would you advise Alice about her chances of developing cancer if she has this allele?

answer

watching

116

views

For unlimited access to Homework Help, a Homework+ subscription is required.

You have 0 free answers left.
Get unlimited access to 3.8 million step-by-step answers.

Get unlimited access

Already have an account? Log in

Reid WolffLv2

22 May 2018

Unlock all answers

Get 1 free homework help answer.

Already have an account? Log in

Related questions

The Case: While Elizabeth is reading the morning newspaper, she notices an ad for a free genetic screening for breast cancer at the clinic next week.The ad specifically invites women of Ashkenazi Jewish ancestry to participate.According to the newspaper ad, subjects will be tested to see whether they have mutations in the BRCA1 gene which would predispose them to breast cancer. Elizabeth, age 27, had heard about the discovery of the gene and about the mutation linked to Jewish women. Her paternal grandmother had been diagnosed with breast cancer at age 51 and died two years later, and Elizabeth worried that she may have inherited a variant that would put her at increased risk. She also worried about her mother, age 52 and apparently cancer-free so far, and her 7- year old daughter. Her daughter is not allowed to participate in the screening, but Elizabeth convinces her mother to go with her to get tested. For the screening, a small amount of blood is drawn. DNA is isolated from the blood, and part of the BRCA1 gene is amplified by PCR. Using a Southern Blot method, the digested DNA is run on a gel, transferred to a neutral membrane. Once on the membrane, the samples are hybridized with specific probes corresponding to deleterous mutations known to be linked to increased breast cancer susceptibility, plus probes for wild type regions of BRCA1. The probe will only bind to the DNA if that mutation is present. Control DNA samples, known to have a specific mutation, are included in the run to verify probe . Probe binding is visualized by labels attached to the probe, and will depend on the lab running the analysis. Probes: 185delAG (AG deletion in exon 2) Normal 185 (no mutation at this site) 4184delTCAA (TCAA deletion in exon 11) Normal 4184 5382insC (C insertion in exon 13) Normal 5382 DNA samples: Elizabeth Mother Unrelated woman Control 185delAG Control 4184delTCAA Control 5382insC Control wild type BRCA1 (no mutations) If either Elizabeth or her mother test positive, is a prophylactic double mastectomy appropriate? (2 marks) What other issues does this type of testing raise, and how should these issues be addressed? (2 marks) What does it mean if a result came back as a Variant of Uncertain Clinical Significance? Provide a peer-reviewed journal article as a reference for this question. (1 mark answer, 1 mark reference) Does the lack of any of these mutations mean that the women will not get breast cancer? (2 marks) Who should have access to the test results? (2 marks) Does the daughter have the right to know the results? She is only seven now, but what about when she is 16? (3 marks) Should this type of screening be mandatory? (3 marks)

a. Design a test or tests that you believe would determine which hypothesis is correct.

b. Describe the results you would expect from your tests if first hypothesis is correct, and also what you would expect if the second hypothesis is correct.

c. Briefly explain to the patient (who is not a scientist) why these results would allow you to determine which hypothesis is correct.

a. Design a test or tests that you believe would determine which hypothesis is correct.

b. Describe the results you would expect from your tests if first hypothesis is correct, and also what you would expect if the second hypothesis is correct.

c. Briefly explain to the patient (who is not a scientist) why these results would allow you to determine which hypothesis is correct.

A patient has been referred to you with an altered bone structure in her hands that resembles the abnormalities produces by mutations of the HOXD13 gene. Two hypotheses have been presented for her: (1) She has a mutation in the coding region of the HOXD13 gene that results in an altered protein that has altered function in the cells of the developing limb bud. (2) The patient has a mutation in the regulatory region of the HOXD13 gene that alters the transcription of this gene, but only in the cells in the developing embryonic limb. a. Design a test or tests that you believe would determine which hypothesis is correct. b. Describe the results you would expect from your tests if first hypothesis is correct, and also what you would expect if the second hypothesis is correct. c. Briefly explain to the patient (who is not a scientist) why these results would allow you to determine which hypothesis is correct.