Genomics overview

Genomics is the study of an organism’s genome – its genetic material – and how that information is applied. All living things, from single-celled bacteria, to multi-cellular plants, animals and humans, have a genome – and ours is made up of DNA.


Counselling and consent


  • Has the patient had enough information and time to consider testing and its consequences?
  • Have the conversation and consent form been documented, recorded and stored according to local policy? Always document consultation as a written letter to the patient and sharing correspondence with the GP.
  • Has the patient been provided with:
    • Record of Discussion Form to sign (this is the consent form: one copy for patient, one for notes)
    • Patient information leaflets
    • Contact details of the clinical team
    • GMS test request form (if using phlebotomy services for blood sampling)
  • Has the patient been informed of logistical procedures including:
    • How the test will be conducted
    • When and how to expect results
    • How to access support whilst waiting for results

Results - key points to cover

Negative: No pathogenic variant detected.

  • No onward referral to Clinical Genetics needed unless:
    • There is a significant family history of breast/ovarian/prostate/pancreatic cancers
    • Age at presentation is very young (<30yrs)
    • Personal history of multiple cancers
  • May need emotional support and reassurance
  • Send generic letter with further details.


Positive: A pathogenic variant is detected in one of the seven genes in R208 panel.

  • Add to MDT for further management discussion:
    • Risk reducing surgery
    • Surveillance
    • Chemoprophylaxis management
    • Referral to Urology (men)
    • Gynaecology (women)
  • Onward referral to Clinical Genetics required:
    • They will arrange cascade testing and provide support for ‘To Whom it May Concern’ Letters to relatives.
    • Inform patients that relatives will need to contact their local GPs for a referral to their nearest regional genetics team.
  • Send generic letter with further details + document in patient’s notes/EPR.


Variant of Uncertain Significance (VUS): A variant is detected in one of the seven genes in R208 panel, but there isn’t enough clinical evidence to link it to cancer yet.

  • These variants may be ‘reclassified’ in the future with more clinical data.
  • Onward referral to Clinical Genetics required
  • Send generic letter with further details + document in patient’s notes/EPR.

Frequently asked questions

  • What is ‘Mainstreaming’?

    Mainstreaming Genomic testing means delivering a genetic test for breast cancer patients who meet the standardised criteria set out in the National Genomic Test Directory. This is a simple blood test that can be ordered by the Breast Cancer Team instead of being outsourced/referred onto an external clinical genetics team.

    The test looks for a ‘Germline’ change in the patient’s DNA sample that might be a contributing factor to their cancer diagnosis.

    The results of the test are ‘actioned’ by the breast team, which include referring the patient to clinical genetics if it is necessary (see ‘How do I and when do I need to refer to Genetics Services?’ FAQ below).

  • Why do we need ‘Mainstreaming’?

    Testing within the breast cancer team speeds up results, reduces the number of healthcare professionals the patient has to interact with and hospital appointments they have to navigate during a stressful time. It ensures the patient can access relevant treatment in a timely manner based on their results.

    The patient will be offered counselling and consent for this blood test in the days after their diagnosis (vs seeing genetics in many places this is a waiting list of more than 3 months).

  • What is the difference between a Germline and a Somatic Change?

    Germline mutations are inherited genetic changes that are present in the DNA of every cell in the body, including sperm and egg cells. These mutations can be passed down from generation to generation and can increase the risk of developing certain diseases, including cancer.

    Somatic mutations, on the other hand, are genetic changes that occur in non germline cells during a person's lifetime. These mutations are not present in every cell of the body and cannot be passed down to offspring. Somatic mutations can occur due to a variety of factors, including exposure to environmental toxins, aging, and errors that occur during DNA replication.

  • How will the results of a positive test affect treatment?

    Results of a positive test will affect treatments in the following ways:

    - Targeted therapies: Established biomarker of PARPi responsiveness, denosumab. Indicative of sensitivity to DNA-damaging chemotherapies, including anthracyclines. Informs use of platinum-based chemotherapy in a neo adjuvant setting.

    - Surgeries: Informs risk-reducing surgery: mastectomies or Bilateral Salpingoophorectomies

    - Surveillance: MRI, Mammogram (NHS Breast Screening Programme Guidelines)

    - Chemoprophylaxis: Tamoxifen, Raloxifene

  • How do I and when do I need to refer to Genetics Services?

    A patient should be referred to Genetics Services when:

    - When patient has a positively identified pathogenic variant

    - When a patient has a variant of uncertain significance (VUS)

    - When a patient has a significant family history

    - When you are not sure.

    Refer to local clinical genetics team, usually using a standardised form via email that will be accessible via your nearest Genomics Laboratory Hub website.

  • How do I calculate a patient’s risk?

    Consider using validated tools recommended and developed by genetics services such as:

    - CanRisk

    - QGenome

    - Manchester Score

  • How do I counsel a patient?

    Please read the genomics toolkit r208 conversation and consent guide to find out more.

Resources and reading list





Webinars and lectures








Reading List

  • Calzone, K. A., Kirk, M., Tonkin, E., Badzek , L., Benjamin, C., & Middleton, A. (2018). The global landscape of nursing and genomics. Journal of Nursing Scholarship, 50(3), 249 256
  • Coulson J. (2022). ‘Understanding the role of genomics in nursing practice.’ Nursing standard (Royal College of Nursing (Great Britain), 10.7748/ns.2022.e12053. Advance online publication.
  • Cuthill, V. (2023), ‘Demystifying Genomics in Cancer Care’, Macmillan Cancer Support. Available at: Demystifying genomics in cancer care | Macmillan Cancer Support
  • Hanson, H., Kulkarni, A., Loong, L., Kavanaugh, G. et al. (2022) ‘UK consensus recommendations of cancer risk for women with germline pathogenic variants in cancer predisposition genes: RAD51C, RAD51D, BRIP1 and PALB2.’ Journal of Medical Genetics, BMJ. 0: 1 13. doi:
  • Launer , J. (2021) ’Effective Clinical Conversations: The Art of Curiosity’ Postgrad Med J, 97, pp 339 340. DOI: Effective clinical conversations: the art of curiosity (
  • NHS England, (2022) ‘Accelerating genomic medicine in the NHS’, NHS England. Available at: NHS England » Accelerating genomic medicine in the NHS
  • Patch, C. & Middleton, A. (2018) ‘Genetic counselling in the era of genomic medicine’, British Medical Bulletin, 126(1), 27 36. DOI:
  • Pichini , A & Bishop, M. (2022) ‘A nationally agreed cross professional competency framework to facilitate genomic testing’ Genetics in Medicine. 24(8), 1743 1752. DOI:
  • Roberts, E., Howell, S., Evans, G. (2023) ‘Polygenic risk scores and breast cancer risk prediction.’ The Breast, 67, 71-77 DOI:
  • Yang, Xin et al. “Cancer Risks Associated With Germline PALB2 Pathogenic Variants: An International Study of 524 Families.” Journal of clinical oncology: official journal of the American Society of Clinical Oncology vol. 38,7 (2020): 674 685. doi:10.1200/JCO.19.01907