part of formation of extrachromosomal circular DNA t-circle formation GO:0090656 biological_process tb A telomere maintenance process that results in the formation of a telomeric circle, or t-circle. A t-circle is an extrachromosomal duplex or single-stranded circular DNA molecule composed of t-arrays. T-circles are involved in the control of telomere length via alternative-lengthening of telomeres (ALT) pathway and telomere rapid deletion (TRD). telomeric circle formation 2015-07-02T11:44:23Z telomere maintenance via telomere trimming