Molecular Diagnostics Services, Inc.
A Contract Research Organization

In Vitro/In Vivo DNA Damage and Repair


Primary DNA damage represents possible premutational events that can be detected, either directly or indirectly, by a number of techniques using mammalian cells in culture or using rodent tissue. The unscheduled DNA synthesis (UDS) assay measures the ability of a test article to induce DNA lesions by measuring the increase in DNA repair.

Autoradiography permits the visualization of DNA repair in cultured rodent hepatocytes. Sister chromatid exchanges (SCEs) represent the exchange, requiring breakage and reunion, of DNA replication products at apparently homologous loci of sister chromatids. Differential staining techniques allow visualization and rapid identification of the exchanges in cultured mammalian cells, as well as in rodent bone marrow or spermatogonial cells.

The COMET assay, also known as single cell gel electrophoresis (SCG), is a microgel DNA electrophoresis technique that detects DNA damage and repair in individual cells. The COMET assay is conducted in both in vitro and in vivo systems and is increasingly being used in genotoxic testing.
| Home | About Us | Services | Newsletter | Careers | Forms | Contact | Search | Site Map |
©2007 Molecular Diagnostic Services, Inc.