Biochemistry Questions Biochemistry Questions / Discuss the different types of satellite DNA and their importance at centromeres.

Satellite DNA are types of repetitive regions of DNA. There are several types:

Microsatellites are short (1-13bp) repeat regions of DNA, with most repeats being 1-4bp. They consist of fewer than 150 repeats.

Minisatellites are repeats of 14-100 base pairs long, forming a tandem array of 1-5kb.

Satellites 100-500bp repeats, forming longer tandem arrays, and typically found at centromeres.

Alphoid Satellite DNA is found at centromeres, distinguishing it from other forms of satellite DNA. This AT-rich repeat region gives a higher order structure which can be recognised by CENP-A, a DNA binding protein found at centromeres to allow binding by mitotic spindles.