Understanding, Diagnosing, and Using Genetic Testing for Basal Cell Nevus Syndrome 2

Expert Reviewed By: ⁠Dr. Brandon Colby MD

Basal Cell Nevus Syndrome 2 (BCNS2) is a rare genetic disorder characterized by the development of multiple basal cell carcinomas, skin abnormalities, and other health issues. Early detection and diagnosis are crucial in managing this condition, and genetic testing plays a significant role in achieving this. This article aims to provide an in-depth understanding of BCNS2, its diagnosis, and the benefits of genetic testing for individuals and families affected by this disorder.

What is Basal Cell Nevus Syndrome 2?

BCNS2, also known as Gorlin Syndrome or nevoid basal cell carcinoma syndrome, is a hereditary condition that increases a person’s risk of developing various benign and malignant tumors, particularly basal cell carcinomas (BCCs). These are a type of skin cancer that arises from the basal cells in the outermost layer of the skin. In addition to BCCs, individuals with BCNS2 may also develop other skin abnormalities, such as palmar and plantar pits, and skeletal anomalies like bifid ribs and jaw cysts.

BCNS2 is caused by mutations in the PTCH1 gene, which is responsible for producing a protein that helps regulate cell growth and division. When this gene is mutated, the protein’s function is disrupted, leading to uncontrolled cell growth and the formation of tumors.

Diagnosing Basal Cell Nevus Syndrome 2

Diagnosing BCNS2 can be challenging due to the wide range of symptoms and their varying severity. A thorough physical examination, medical history review, and imaging studies (such as X-rays or MRI) can help identify the characteristic features of the syndrome. However, a definitive diagnosis can only be made through genetic testing.

Genetic Testing for BCNS2

Genetic testing is a powerful tool that can help confirm the diagnosis of BCNS2 and provide valuable information for affected individuals and their families. There are several types of genetic tests available for BCNS2, including:

• Mutation analysis: This test involves sequencing the PTCH1 gene to identify the specific mutation causing the disorder. It is the most accurate and reliable method for diagnosing BCNS2.
• Deletion/duplication analysis: This test is used to detect large deletions or duplications in the PTCH1 gene that may not be identified by mutation analysis.
• Linkage analysis: This test is used when the specific mutation causing BCNS2 in a family is unknown. It involves analyzing the inheritance patterns of genetic markers near the PTCH1 gene to determine if an individual is at risk of developing the disorder.

Genetic testing for BCNS2 can be performed on a blood or saliva sample, and the results are usually available within a few weeks. It is important to note that genetic testing has some limitations, and a negative result does not always mean that a person is not affected by BCNS2. In such cases, further testing or clinical evaluation may be necessary.

Benefits of Genetic Testing for BCNS2

There are several advantages to undergoing genetic testing for BCNS2, including:

• Confirmation of diagnosis: A positive genetic test result can provide a definitive diagnosis, helping to guide appropriate treatment and management strategies.
• Early detection and intervention: Identifying the presence of BCNS2 early in life can help affected individuals and their families take preventive measures to reduce the risk of developing BCCs and other complications.
• Family planning: Genetic testing can help couples who are carriers of BCNS2 make informed decisions about family planning and prenatal testing options.
• Psychosocial support: A confirmed diagnosis can provide relief and clarity for affected individuals and their families, allowing them to access appropriate support services and connect with others who share their experiences.

In conclusion, genetic testing is a valuable tool in the diagnosis and management of Basal Cell Nevus Syndrome 2. By understanding the genetic basis of this disorder, affected individuals and their families can make informed decisions about their health and well-being, and take appropriate steps to reduce the risk of complications.

About The Expert Reviewer

Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of  and the author of ⁠⁠Outsmart Your Genes.

Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (⁠⁠ACMG), an Associate of the American College of Preventive Medicine (⁠⁠ACPM), and a member of the National Society of Genetic Counselors (⁠NSGC)