Microchromosome

Microchromosome is a small chromosome. They are less than 20 Mb in size. The chromosomes that are greater than 40 Mb in size are called Macrochromosome. The length of chromosomes is generally measured in bp, kb, Mb, Gb; bp means base pair, 1 bp = 618 or 643 dalton. Daltons is the basic measure of chromosomes. 1 kb = 1,000 bp. 1 Mb = 1,000,000 bp. 1 Gb = 1 billion bp.

About Microchromosome

They are rich in genes and GC content. GC content is Guanine-cytosine content. It is the percentage of nitrogen present in the DNA or RNA. Earlier, the microchromosome was considered insignificant. However, it was later found that hold valuable information and have major role in evolution. The microchromosome are of great help in ordering and identifying chromosomes.

Microchromosome in birds, turtles and humans

• The microchromosome are abundant in birds.
• The microchromosome is used in sex determination of turtles.
• There are no prominent evidences to prove that the microchromosome are found in humans. This is because, chromosome 21 is the smallest chromosome in humans. It is 47 Mb, which means, all the chromosomes in humans are macrochromosomes. However, there are certain facts that relate microchromosome and down syndrome disease in humans.

Microchromosome – Building blocks in vertebrates

In November 2021, it was found that the Microchromosome has bigger role in mammals. Every time a new evolution occurs in mammals, there was a change in the microchromosome. They are the main reason behind the evolution of a new mammal. They are the building blocks in vertebrates. Vertebrates are those organisms with backbone. It was also found that the microchromosome crowd together in the centre of the nucleus exhibiting functional coherence. That is, all the microchromosome in the cell function together.