#ExistInterpData>Background Information for: Juvenile Polyposis Syndrome (BMPR1A) Sequencing and Deletion/Duplication:
Characteristics: Multiple juvenile (hamartomatous) polyps in the stomach, small intestine, colon, and rectum. Risk for colon cancer is 20 percent by age 35 and 70 percent by age 60.
Incidence: 1 in 16,000 to 100,000 individuals.
Inheritance: Autosomal dominant.
Penetrance: Greater than 90 percent for polyp development.
Cause: Pathogenic BMPR1A and SMAD4 mutations.
Clinical Sensitivity: Approximately 24 percent.
Methodology: Bidirectional sequencing of the entire BMPR1A coding region and intron-exon boundaries. Multiplex ligation-dependent probe amplification (MLPA) to detect large BMPR1A coding region deletions and duplications. BMPR1A exons 6 and 7 are not tested by MLPA.
Analytical Sensitivity & Specificity for Sequencing and MLPA: 99 percent.
Limitations: Rare diagnostic errors can occur due to primer or probe site mutations. Regulatory region mutations and deep intronic mutations will not be detected. Large deletions/duplications of exons 6 and 7 will not be detected. The breakpoints of large deletions/duplications will not be determined. Mutations in genes other than BMPR1A are not evaluated.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.
See Compliance Statement C: www.aruplab.com/CS
||BMPR1A (Juvenile Polyposis Syndrome (BMPR1A) Sequencing and Deletion/Duplication)