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MARFAN SYNDROME:
DIRECT MUTATION DETECTION
Marfan disease is a result of defects in the connective
protein fibrillin. This disorder results in individuals that can be very tall
and thin, have pectus excavatum (depression under the sternum in chest), and
develop cataracts and/or dislocated retinas. Defects in the aorta (mitral valve
prolapse, aortic dilation, and aortic aneurysm) can be life threatening -
especially for pregnant women. In the United States, it is estimated that 1 in
10,000 are at risk for developing Marfan disease. However, the risk may be much
higher because many cases remain undiagnosed due to variable expression.
Most Marfan disease is inherited in an autosomal dominant pattern as the result of a
defective fibrillin gene located on chromosome 15. However, a large proportion
of cases appear spontaneous and variable expression can obscure the inheritance
patterns. Therefore, direct testing for the mutations is often the only way to
confirm the disease in many patients. Detection of mutations by sequencing of
the fibrillin gene ranges from 35% to 85% depending on family history.
REASONS FOR REFERRAL:
- Individuals with potential Marfan disease who want to assess the need for
regular echocardiograms, and assess the risk of high stress physical activity
such as competitive sports or pregnancy.
- Individuals with potential Marfan disease who wish to undergo prenatal or
preconception testing.
- Individuals who are tall and have eye or heart problems.
- Individuals with Marfan-like symptoms but no family history.
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TESTING METHODOLOGY:
- The choice of testing strategy involves many factors. A
discussion with the laboratory is recommended before sending a specimen.
SPECIMEN REQUIREMENTS:
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Live fibroblasts- either cultured or as a
skin biopsy.
Due to the sensitivity of the specimen, it is highly recommended that the cells
be cultured by a facility as close to the collection site as possible. However if desired, the skin biopsy may be sent
directly, and the culture will be grown at our facility. Please note that an
additional cost will be incurred; add CPT code
88233 for this service.
TURNAROUND TIMES:
Complete gene analysis (DNA): 6 - 8 weeks
Complete gene analysis (RNA): 6 - 8 weeks
Neonatal Marfan DNA Analysis (exons 24-32): 3 weeks
CPT CODES:
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