Collect whole blood in a purple top (EDTA) tube.
Refrigerate sample until shipment. Send the sample at room temperature with overnight delivery for receipt Monday through Friday within 24 hours of collection.
Whole blood can be refrigerated until shipment.
Heparinized specimens, severely hemolyzed specimens, frozen, clotted or possibly commingled specimens, blood in non-sterile or leaky containers, mislabeled or inappropriately labeled specimens.
Do not heat, freeze or centrifuge blood before shipment. Refrigerate sample until shipment.
Mon - Fri 9:00am to 4:00pm
Multiple Endocrine Neoplasia type 2 (MEN 2) is an autosomal dominantly inherited cancer disorder classified in to three subtypes: MEN 2A, MEN 2B and familial medullary thyroid carcinoma (FMTC). All three subtypes carry a high risk for development of medullary carcinoma of the thyroid (MTC). The onset of MTC is in early childhood in MEN 2B and early adulthood in MEN 2A.
MEN2A is characterized by medullary thyroid carcinoma, pheochromocytoma, and parathyroid hyperplasia. MEN2B is characterized by bilateral medullary thyroid carcinoma, pheochromocytoma, diffuse ganglioneuromas of the intestinal tract, mucosal neuromas, and skeletal abnormalities. Symptoms of MEN2B are evident within the first decade of life and progresses rapidly.
Approximately 95% of families with MEN 2A have a mutation in exon 10 or 11 of the RET proto-oncogene. Approximately 95% of individuals with the MEN 2B phenotype have a single point mutation in the tyrosine kinase of the RET proto-oncogene at codon 918 in exon 16. Approximately 85% of patients with FMTC have an identifiable mutation in exons 10, 11, 13, 14 or 15 of the RET proto-oncogene.
We offer DNA sequence analysis of exons 10, 11, 13, 14, 15 and 16 of the RET proto-oncogene. The patient’s gene sequence is then compared to a reference sequence. Sequence variants are classified as mutations, variants of unknown significance or benign variants unrelated to disease. Variants of unknown significance may warrant further studies in the patient and other family members. Mutations in other exons, promoters, deep intronic regions and other regulatory regions will not be identified with this assay.
In 95% of MEN2A cases and 85% of familial medullary thyroid carcinoma patients, the mutation involves one of five cysteine residues in the extracellular domain of the RET proto oncogene. In greater than 95% of MEN2B cases, there is a mutation at a single position within the extracellular ligand-binding domain of the RET proto-oncogene. The analytical sensitivity for sequencing is close to 100%.
Known mutation analysis is available to family members for mutations previously identified by sequence analysis.
Test results with interpretation will be mailed and/or faxed to the referring physician following completion of the test. Additional reports will be provided as requested.
The clinical utility of these assays is in confirming a clinical diagnosis of MEN 2A, facilitate pre-symptomatic testing of at risk relatives, confirm the need for clinical surveillance or surgery in patients positive for a mutation, and to facilitate prenatal diagnosis.
Whole blood in EDTA purple top tubes is the preferred sample. High molecular weight genomic DNA, cheek epithelial cells, or other samples containing DNA may be acceptable. Contact the laboratory for specific instructions regarding such samples before sending the sample.
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