Mutations in MutS/L components can lead to hereditary nonpolyposis colorectal cancer (HNPCC). A characteristic feature of HNPCC is microsatellite instability, in which the lengths (numbers of repeats) of microsatellite sequences change rapidly in the tumor cells due to the loss of the mismatch repair system to correct replication slippage in these sequences.

TLS Online TPP Program

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#Unit 3. Fundamental Processes

 Telomeric sequences can be written in the general form Cn(A/T)m, where n >1 and m is 1 to 4.

TLS Online TPP Program

#Id: 658

#Unit 3. Fundamental Processes

TTAGGG repeats with size of 3–20-kb are telomeres of human chromosomes.

TLS Online TPP Program

#Id: 659

#Unit 3. Fundamental Processes

Telomeric sequence is the extension of the G-T–rich strand, which for 14 to 16 bases is usually a single strand.

TLS Online TPP Program

#Id: 660

#Unit 3. Fundamental Processes

G-tail is probably generated because there is a specific limited degradation of the C-A–rich strand.

TLS Online TPP Program

#Id: 661

#Unit 3. Fundamental Processes

Drosophila telomeres are an exception, consisting of terminal arrays of retrotransposons.

TLS Online TPP Program

#Id: 662

#Unit 3. Fundamental Processes

Telomeres cluster on the nuclear envelope just prior to homologous chromosome synapsis during meiosis.