Capital Biosciences provides services for detection of Alternative Lengthening of Telomeres (ALT), estimation of telomere length and telomerase activity.
CBI has successfully applied qPCR to the detection of ALT activity (CC-ALT qPCR) by measuring both telomere content and telomere C-Circle DNA that is specific for ALT. The sensitivity of our qPCR-ALT assay is >25 times higher than standard radioisotope dot blot hybridization methods. We also offer research-use kits and control reagents for the C-Circle DNA assay.
Telomeres are ends of chromosomes in mammalian cells. They represent stretches of TTAGGG repeats and are maintained during normal cell proliferation. Telomere maintenance mechanisms (TMM) counteract the innate telomere loss accompanying linear chromosome replication by synthesizing new telomeric DNA from either an RNA template using telomerase or a DNA template using Alternative Lengthening of Telomeres (ALT). The ALT mechanism involves recombination-dependent DNA replication using either the same telomere or another telomere, or possibly extrachromosomal telomeric DNA as the copy template. The ALT mechanism generates sudden, large increases in telomere length, consistent with either a long linear telomeric template or a rolling mechanism, such as rolling circle amplification. DNA recombination proteins known to be required for the ALT mechanism also have other essential roles, so telomere length maintenance by ALT may result from dysregulation of normal DNA repair and replication processes.