Clinical Laboratory - Molecular Diagnostics

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Molecular Diagnostics

Screening, Diagnosing, and Monitoring of Infectious, Genetic and Oncologic Diseases

Molecular diagnostics rely on detection of genetic material. These can include:

  • Genetic DNA or RNA sequences, typically with polymerase chain reaction (PCR).

  • Fluorescence in situ hybridization (FISH) may detect small regions of a chromosome, or abnormalities in a chromosome such as deletions or translocations.

Genetic sequences with DNA are highly specific for infectious agents, and can help in diagnosis and identification of microbial infections. PCR may be particularly helpful when infectious agents cannot be cultured (such as Pneumocystis) or are difficult to culture (Legionella).

Molecular diagnostics may be applied in oncology, to determine genetic sequences diagnostic of a particular malignant neoplasm. However, one should be aware that most cancers tend to be sporadic, even those that tend to run within families. Increased age remains one of the most well-known risk factors for the development of cancer.

Molecular diagnostics may detect genetic polymorphisms with DNA sequences that may indicate what drug therapies may be most effective or whether drugs may be metabolized at different rates in patients.

Molecular testing can be expensive - in the hundreds to potentially thousands of dollars. Therefore, consideration of the indications for testing is paramount before ordering these tests.

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