Final answer:
Satellite DNA consists of highly repetitive sequences in the eukaryotic genome, often found in heterochromatic regions such as centromeres and telomeres.
Step-by-step explanation:
Understanding Satellite DNA
Satellite DNA refers to repetitive sequences found in the DNA of eukaryotic organisms.
These sequences do not code for proteins and often consist of short sequences repeated thousands of times in tandem.
They were first demonstrated experimentally through cesium chloride (CsCl) density gradient centrifugation which separates molecules based on their density.
The fragmented DNA separates into a main band and a minor band of different density, with satellite DNA forming a distinct minor band due to its different base pair composition.
Satellite DNA is often found in the heterochromatin regions of chromosomes, such as centromeres and telomeres.
However, because of its highly repetitive nature, satellite DNA is not useful for establishing evolutionary relationships between species.
This is because it undergoes mutation at a rate different from that of coding sequences, making it less reliable for comparisons across species.
Sequencing satellite DNA can be challenging due to its repetitive nature.
The presence of many identical or near-identical repeats within the sequence makes it difficult to correctly assemble the DNA sequence using conventional sequencing technologies.
The Sanger method of DNA sequencing and other sequencing technologies rely on unique sequences to align and assemble DNA fragments, which is problematic when dealing with highly repetitive sequences such as satellite DNA.