Conditions & Treatments

Neurofibromatosis Type 1 - Diagnosis

Who should undergo genetic testing for NF1?

If you or your family members meet the following criteria, genetic testing should be considered to confirm the diagnosis of NF1.

Individuals who exhibit features of NF1 and would like to confirm the diagnosis of NF1
Individuals who have family members with a previously identified faulty NF1 gene
Individuals with NF1 who are planning for a family and are interested in assisted reproductive technologies

How is genetic testing done?

Genetic testing is typically a one-time blood test. If a blood sample cannot be taken, other sample sources (e.g., skin or saliva) may be explored.

What are the possible results of genetic testing?

There are 3 types of results you may receive:

Positive	Uncertain - Variant of Uncertain Significance (VUS)	Negative
Faulty gene(s) identified	Uncertain gene change(s) identified, unclear if these change(s) increase risk for tumours and cancers	No faulty gene(s) identified
Increased risk of developing certain tumours and cancers (depends on faulty gene(s) involved)	May be clarified by testing other family members	If you have been clinically diagnosed with NF1, you may still have an increased risk of certain tumours and cancers. Your doctors will personalise a screening and management plan for you accordingly.
Your family (parents, siblings, children and extended relatives) may have inherited the faulty gene(s) and should consider genetic testing to clarify this	May be reclassified over time as ‘positive’ or ‘negative’ when more information is known	Test limitations will be explained in the context of your personal and family history of clinical features

How can your genetic test result help you?

Personalised management
The genetic test result may help to personalise management options based on one’s tumour/cancer risk.

If you have a cancer diagnosis
- Can help guide and personalise treatment options
- Can help understand what other tumours/cancers you are at risk of and how to manage these risks
If you are currently cancer-free
- Can guide relevant screening options to detect tumours and cancer at their earliest, most treatable stage
- Can help individuals with NF1 to consider dedicated reproductive options when planning to have children

A genetic test result can also help one to understand if other family members are at risk of NF1. Family members can then consider their own testing (predictive testing) to clarify carrier status and determine their tumour/cancer risks.