GENE PREDICTION AND COUNTING

It has been found out by using the sequencing technique that although the higher mammals are more complex, the number of genes do not increase likewise. The human beings (-30,000 genes) have only 1/3 rd more genes then the worms (-18,000). This phenomenon is still a paradox to scientists and is called C-value paradox. The C-value paradox indicates that despite the increasing complexity in higher mammals the numbers of genes do not increase likewise.
In human genome only less than 5% of the total sequence, codes, rest are either regulatory in nature such as the splice sites, intron and enhancers or they are simply called Junk DNA.

 

Table showing the genome size and gene predictions between several different organisms

Genome size in base pairs	Organism	No. of chromosomes	The number of predicted genes	Part of the genome that encodes for protein
500,000	Bacteria, E.Coli	1	5000	90%
14,000,000	Yeast, S. cerevisiae	12	6000	70%
100,000,000	Worm, C. elegans	6	18,000	27%
300,000,000	Fruit Fly, D. melanogaster	4	14,000	20%
125,000,000	Weed, A. thaliana	5	25,500	20%
3,000,000,000	Human, H.sapiens	23	30,000	<5%