Why Do Humans Have So Few Genes?

Answer 1

How many were you expecting?

The initial results of the Human Genome Project used a strict set of criteria to count genes. The definition of gene is getting more and more complicated as we continue to discover how life works. There are genes that can generate thousands of different proteins depending on how they are processed (such as alternative splicing and RNA editing) so a single chunk of DNA can lead different proteins in different cells at different times. There are genes for non-coding RNA where the RNA is the functional end product (such as miRNA, piRNA). The total number of genes in humans is still about 30,000 which is about the same for a mouse and not that much more than a fruit fly. (By the way, the diploid chromosome number for mouse is 40, or 19 pairs of autosomes and one pair of sex chromosomes but mice actually have 100 million more total DNA bases than humans).

The difference in complexity between species seems to be determined by how the genes are processed. If you count the major splice variants there are about 100,000 proteins in the human proteome. Count post-translational modifications and then the number of different proteins is over a million.

Answer 2

I think that the term "few" is quite relative. Current predictions from sequencing projects have "estimated" the total number of genes in humans to be around 30,000 as others have already answered. However, this is only the beginning. The majority of variation comes from everything after the "static" nature of a specific gene. Alternative splicing of primary RNA molecules produced from a single gene can lead to as many as 50 to 100 different mRNAs and proteins. RNA editing can change the sequence, and the biologic behavior, of specific translated gene products. Post-translational modifications, including glycosylation, prenylation, phosphorylation, acetylation, methylation, etc. all can and do change the behavior of a given protein. Recent estimates of the total numbers of variations in proteins produced in a cell range from 200,000 to over 1,000,000. Not bad starting from only a "few" genes. And never mind the "downstream" effects that these modified proteins can cause both within the cell in which they are produced as well as on other cells where they might also act.

Answer 3

Humans have 30,000 genes according to the Human Genome Project and it is the interaction between these genes and expression as proteins which is responsible for the variability amongst humans. As of now even these 30, 000 genes seem so vast and have not been studied completely.

Answer 4

Human does have near 400.000 gene , the reason of the short DNA or the No# of chromosomes is only 23 pair,(mouse 40 pair) due to the shortage of Nonsense intrones in the genome

Answer 5

i'm no longer likely to wager. with the help of ways, evolution has no longer something to do with the soul and God. Evolution comes from inheritable characteristics by ability of organic selection. That being stated, neither is conceived in straightforward words made up. "technology Geek: The human recommendations advanced to be counted on God and a soul. decrease primates likely do no longer have those beliefs, how is evolution the incorrect time period the following?" -you No madam you're incorrect. Like I and technology Geek have stated, God and soul isn't inherited. speedy get at the same time for you. -all and distinctive isn't born with faith, the conception in a soul, Math, writing, analyzing, technology, and time. All of those are realized. this can be best besides the undeniable fact that. -The human recommendations advanced, and throughout it the conception of God and soul replaced into created. It cant be stated that the recommendations advanced to be counted on God because the recommendations won't be able to evolve with recommendations, in straightforward words organic selection.

Answer 6

Our replication cycle is orders of magnitude longer than that of microscopic creatures. They have much more opportunity for gene replication errors.

Answer 7

few??
some humans (my daughter for instance) have dozens and dozens of jeans

not just blue but other colors too, and different kinds of cut and sizes, you wouldn't believe what her closet ...

oops...., oh sorry, ... the question was about "genes", my bad

Answer 8

Yeah i only have a few, I could use about 2 or 3 more, preferably Levi's.

Answer 9

because we have 23 pairs of chromosomes, the number doesn't really determine the complicity of the organism lettuce has over 193 pairs of chromosomes.

Answer 10

FEW GENES!?!?

Oh, my.