Name of the Procedure:

MSH6 (mutS homolog 6 [E. coli]) Gene Analysis; Known Familial Variants

Summary

MSH6 gene analysis is a genetic test used to identify specific known mutations in the MSH6 gene that can be inherited within families. These mutations are linked to an increased risk of certain cancers, particularly those associated with Lynch syndrome, also known as hereditary non-polyposis colorectal cancer (HNPCC).

Purpose

The procedure aims to confirm the presence of known familial variants in the MSH6 gene, which helps in diagnosing Lynch syndrome. Identifying these genetic mutations allows for personalized cancer risk management and early detection strategies.

Indications

• Family history of Lynch syndrome or hereditary non-polyposis colorectal cancer.
• Individuals from families with a known MSH6 mutation.
• Patients with early-onset or multiple types of cancer associated with Lynch syndrome, such as colorectal or endometrial cancer.

Preparation

• Genetic counseling is recommended prior to testing to discuss potential outcomes and implications.
• No specific dietary or medication restrictions are generally required before the test.
• A blood sample is typically obtained; in some cases, a saliva sample may be used.

Procedure Description

1. A healthcare professional collects a blood or saliva sample from the patient.
2. The sample is sent to a specialized laboratory where DNA is extracted.
3. The laboratory performs a genetic analysis to detect known familial variants in the MSH6 gene.
4. Results are analyzed and interpreted by a geneticist, who then shares the findings with the patient's healthcare provider.

Duration

The sample collection takes about 15-30 minutes. The genetic analysis process can take several weeks, typically between 2-6 weeks, to complete and return results.

Setting

The sample collection is performed in a healthcare provider's office, outpatient clinic, or hospital. The actual genetic analysis is conducted in a specialized laboratory.

Personnel

• Genetic Counselor
• Phlebotomist or nurse for sample collection
• Geneticist for analysis and interpretation

Risks and Complications

• Minor discomfort or bruising at the blood collection site.
• Emotional implications related to the test results, which should be managed through genetic counseling.
• No significant medical risks are associated with the genetic testing itself.

Benefits

• Early identification of Lynch syndrome risk allows for personalized surveillance and preventive measures.
• Enables family members to also be tested and take precautionary steps if they carry the familial variant.
• Improved cancer risk management and screening protocols.

Recovery

• No physical recovery is needed as the procedure is non-invasive.

• Psychological support may be beneficial in understanding and coping with the test results.

  Alternatives

• Comprehensive genetic testing that examines the entire MSH6 gene for any mutations, not just known familial variants.
• Screening for other related genes associated with Lynch syndrome, such as MLH1, MSH2, PMS2, and EPCAM.

Patient Experience

• The patient may experience slight discomfort during blood collection.
• Results are shared with the patient through a follow-up consultation with their healthcare provider or genetic counselor, where further steps and preventive measures are discussed.
• Emotional reactions are common and are addressed with the help of a genetic counselor.