Patent ID: 6789022
Filing Date: 2004-09-07
Classification: C12Q

Abstract:
A method for detecting and quantifying clustered damages in DNA, the method comprising:a) providing a sample containing DNA to be assayed for clustered damages; b) contacting a first aliquot of the DNA to be tested for clustered damages with one or more lesion-specific cleaving reagents under conditions appropriate for cleavage of the DNA to produce single-strand nicks in the DNA at sites of damage lesions; c) quantitatively determining the number average molecular length (Ln) of double stranded DNA in the lesion-specific cleaving reagent-treated first aliquot; d) quantitatively determining the number average molecular length (Ln) of double stranded DNA in a second aliquot of the DNA to be tested for clustered damages, the second aliquot being untreated by lesion-specific cleaving reagents; e) calculating the frequency of clustered damages (&PHgr;c) in the DNA to be assayed for clustered damages using the following equation: &PHgr;c=1/Ln(+enzyme)âˆ’1/Ln(âˆ’enzyme) wherein Ln(+enzyme) is the number average molecular length of double stranded DNA determined for the lesion-specific leaving reagent-treated DNA determined in step c), and Ln(âˆ’untreated DNA in step d).