Satellite DNA and its Characteristics

Satellite DNA consists of very large arrays of tandemly repeating, non-coding DNA. It is the main component of functional centromere and forms the main structural constituent of heterochromatin.

The name 'satellite DNA' refers to how repetitions of a short DNA sequence tend to produce a different frequency of the nucleotides and thus have a different density from bulk DNA, forming a second or 'satellite' band when genomic DNA is separated on a density gradient.

The types of satellite DNA in humans are α (alphoid DNA) located on all chromosomes, β located on most chromosomes, Satellite 1 located on centromeres of chromosomes 1, 9, 13, 14, 15, 21, 22 and Y, and Satellite 2 and Satellite 3 located on most chromosomes.

<p>A repeated pattern can be between 1 base pair long (a mononucleotide repeat) to several thousand base pairs long. Most satellite DNA is localized to the telomeric or the centromeric region of the chromosome.</p> Signup and view all the answers

<p>Microsatellites are thought to have originated by polymerase slippage during DNA replication.</p> Signup and view all the answers