Measures of abundance of short telomeres

摘要

A method for amplifying telomeric repetitive sequences and subtelomeric sequences from a chromosome comprising: a) creating a nucleic acid extension product by the steps of: i) hybridizing an extension primer with a telomeric repetitive sequence in a 3 'overhang of DNA double-stranded chromosomal, where: (1) the double-stranded chromosomal DNA has a telomeric region comprising repetitive telomeric sequences and a subtelomeric region comprising subtelomeric sequences; and (2) the extension primer comprises: (A) a 3 'portion that hybridizes to a telomeric repetitive sequence at the 3' overhang under mating conditions, and (B) a 5 'portion that has an anchor sequence that does not hybridizes to a telomeric repetitive sequence in the 3 'overhang under the mating conditions; and ii) performing a time-controlled strand shift extension reaction to extend the extension primer into the subtelomeric region of the double-stranded chromosomal DNA, where the time of the extension reaction is controlled so as to generate an extension product. comprising both telomeric repetitive sequences and subtelomeric sequences only in the case of double-stranded chromosomal DNA having a telomeric region whose length falls within a predetermined range; and b) amplifying by means of a subsequent PCR reaction the sequences of the extension product, thus producing an amplification product of limited length comprising nucleic acids with repetitive telomeric sequences and subtelomeric sequences, where the time of said time-controlled extension reaction is controlled. so as to generate an extension product whose length is within a predetermined range, where the extension reaction time is controlled to 0.1 to 30 minutes, 0.1 to 10 minutes, 0.1 to 5 minutes, 0 , 1 to 4 minutes, 0.1 to 3 minutes, 0.1 to 2 minutes, no more than 0.1 to 1 minute, or 0.1 to 0.5 minutes.