Genome Surprise

Catskul writes "Along with the news that the polished and (more nearly) complete human genome being published Monday, comes a surprising observation about the genome: We have substantially fewer genes than expected; between 27,000 and 40,000 as compared to an original estimate of 140,000." Update: 04/14 01:22 GMT by T : For everyone who can't look at a Z, headline updated with an S in "surprise."

Comments

I thought so.

[Capt'n Hector]

We are simple creatures, no doubt. But the number of genomes does not point to our complexity. Rather, these genomes could be incredibly complex, controlling all sorts of things. They could intermingle, with no clear linear relationship between a single function and a single genome. It would have been easier to decode had there been more, because now it is clear that these genomes are more complex than originally thought.

Re:I thought so.

[glwtta]

Frankly, I would have more faith in your scientific reasoning if you knew the difference between a gene and a genome.

Re:I thought so.

[Spy Hunter]

Yeah, I was astonished at the stupid claims being made in the article based on this percieved lack of genes.

The small number of genes is significant [because it means] we're not hard-wired

It means no such thing! It could just mean that fewer genes are necessary to hard-wire us. Nobody really knows how much effect particular genes have on us, so saying that 140,000 would be enough but 40,000 isn't enough is just spewing hot air.

The low number of genes means humans have as few as 300 more genes than a mouse and only twice the genes of the fruit fly. "A lot of people will find that philosophically disturbing," says theoretical biologist Jean-Michel Claverie

I don't see why they should. More genes == more superiority? Who made up that rule? How about "better genes == more superiority"?

The low number of genes [means] that there is no genetic basis for race.

Totally not true. Of course race has a genetic basis. It is inherited, after all. Black people have black children. It just means that the number of genes necessary to determine race is smaller than we thought.

...how have we become so much more complex than other creatures, whilst having relatively few extra genes.

I don't think it's any mystery. We're NOT "so much more complex!" The only part of us that is more complex is our brains. And animals have brains too, some of which are quite sophisticated by any measure of complexity.

Looks like people are having a field day speculating about what this low number could mean. I think it just means that we were wrong before, and we still don't have a clue about how big an effect single genes can really have on an organism.

Re:I thought so.

[skywire]

Of course race has a genetic basis. It is inherited, after all. Black people have black children.

If you were talking about skin colour, then this would make sense. But you are speaking about 'race', which is a word that is used to refer to a fuzzy concept that has no clear scientific definition. You might as well have said "Of course phlogiston flows. Things do change temperature, after all."

Re:I thought so.

[gilroy]

Blockquoth the poster:

I don't see why they should. More genes == more superiority? Who made up that rule? How about "better genes == more superiority"?

What the heck does "better genes" mean? For that matter, what does "more superiority"? Despite what everyone seems to want, evolution is not a moralistic process! There is no "superior" or "inferior". At best, there is "more fit" and "less fit" -- and even that is strongly location-dependent and time-evolving. In terms of survival fitness, it can be argued that, say, bacteria -- or insects -- way outperform humans. Sure, they don't build cathedrals or rocket ships, but what the heck does evolution care?

Re:I thought so.

[danudwary]

The brightest minds of biology did, over 10 years ago... and so the central dogma of biology ("one gene => one protein => one function") was taught to a generation of students.

Sorry. The "Central Dogma" is DNA->RNA->protein. Still true. Only the ignorant have misinterpreted it that way.

(It's also been added to. For example we now know that occasionally RNA->DNA and once in a great while DNA->protein.)

Re:I thought so.

[Rutulian]

The brightest minds of biology did, over 10 years ago... and so the central dogma of biology ("one gene => one protein => one function") was taught to a generation of students.

Actually that is not the central dogma of biology. The central dogma is DNA -> RNA -> Polypeptide (Ref: Russell, Genetics, 1998). The one-gene one-enzyme hypothesis was proposed a long time ago, and yes it did earn a Nobel Prize, but it has since been altered to the one-gene one-polypeptide hypothesis. Gene expression has proved to be much more complicated than anyone initially thought.

Re:I thought so.

[gene_tailor]

>Just because an idea is imprecise does not mean it does not exist

It may exist in sociology, but not in genetics. Race is not a genetically valid concept. It is true that there are genetic differences between groups, but genetic studies have found that the amount of variation WITHIN each group is larger than that AMONG various groups. Attempts to predict race/ethnicity etc. from genetic sequence have all failed. The few differences among our genes that produce physically visible traits are tiny compared to the number of possible variations visible at the molecular level.

The less one makes declarative statements...

[eidechse]

"What we've got now is what we'll have for all eternity"

Perhaps in the future we'll get to see this next to:

"Everything that can be invented has been invented." -Charles H. Duell

"640k should be enough for anybody." - Bill Gates

I grant that this particular case may seem less "philosophical" than the cases in the quotations above but a "stick a fork in it...it's done" mindset is not only arrogant but detrimental to science as well.

Re:Political correctness again loses against reali

[drooling-dog]

So, if a child is born to an interracial couple, the child's race is...?

The point is that the genetic differences behind our racial distinctions are really quite miniscule. The closer you look at them, the harder it is to divide humans into well-defined categories. It is you, I'm afraid, who are holding to a politically-motivated viewpoint that is divorced from reality.

The proteins are where the fun is at

[Jman314]

Not to undermine the significance at mapping the genes, but they're the first step. The next is proteins, the building blocks of life described in DNA. They do everything, so naturaly they are being studied closely by biologists and drug companies.

So what if there is fewer genes than expected? It means that the means of describing protiens is not linear. Protiens can fold four different ways, offering many different structural combinations.

The highest level biological system we understand completely is a species of yeast. For a human, the interactions that make the system work are almost unimagineably complex, because there are so many variables. We're just beginning to model them accurately.

Complexity of life is more than just genes.

Re:Just for comparison's sake...

[dspeyer]

Not to argue with your basic idea there, but how does culture determine the similarities then? The fact that most native Africans have dark skin, most Northern Europeans are relatively fair skinned, and most Asians are notably shorter than Native Americans? There has to be some genes doing something. Or some other mechanism we have yet to discover.

Dark-skinned is not a race. "Black" is a race -- and very few black people have actual black skin (much less black teeth!). Races are cultural constructs that may include genetic/physical characteristics in their definitions. Some physical characteristics are often considered (e.g. skin color) and some (earlobe attatchment, blood type) are generally ignored. Furthermore:

• USA custom dictates that an individual with one great-great-grandfather from Nigeria and the rest from England is black, completely irrespective of any alleles the individual may actually express or carry.
• USA custom acknowledges "Hispanic" as a race, even though it carries no genetic correlation. It is roughly defined as an individual who's native language is an American dialect of Spanish, or the decendant of such a person to the fourth generation. Except Jamacans, who might be black. And including Haitians and Brazilians, or something like that.
• Mexican custom dictates that an individual with one nigerian parent and one Castillian is black, mulatto, or white depending on the individual's net income. (Disclaimer: I haven't been to Mexico -- this is the finding of some random ethnographer.)

What's probably most significant, though, is that the races which do correspond to genetic traits make no sense as biological characterizations. They don't match actual genetic difference groups at all. This is what is meant by the statement that races are purely cultural.

"genetic" does not mean "hard-wired"

[roffe]

It's been a popular misconception in the popular media for a long time that traits that are learned are malleable, whereas traits that are innate or genetic are not. This is not the case. The malleability of a trait depends on how it is implemented in the body, not on whether it is inborn or learned.

The simplistic view of the importance of genetic contribution probably stems from the way genetics is taught in school. Your eye color is genetically determined and eye color does not change. However, the reason why eye color does not change is not that it is inherited by genetic inheritance, but because eyes are constructed the way they are.

This is one of the reasons why psychologists worry much less about heritability of traits than they used to. The malleability of any given trait remains an empirical question. Your genes don't know how heritable they are.

For an interesting discussion of heritability and malleability, read Plomin et al's Behavioural Genetics - or the brief version here.

Re:Just for comparison's sake...

[gobbo]

Aw hell, there go my mod points.

Race is not much more than a way of classifying people based on appearance. It might also hint at a shared cultural background, but not always. But it is still potentially useful.

Well, for sociology nerds, it's important to remember that 'race' as a concept doesn't really exist outside of a discourse of oppressive relationships, since its historical origins as a concept were so bound up in the overdetermining of slavery as a 'natural' practice.

Not that anyone who uses the term is being oppressive. You are right to some degree, that the term is often used as a way of pointing at appearance linked to geographic heritage. But that nasty history is carried along with the word and the way the institutions of the world deal with it. Yes, words like that always have complex meanings.

Anyone who examines the quagmire that is Race Politics in N.A. (which influences the discourse of race throughout the world) has to admit that oppression, repression, taboo, and resistance are not yet dissociated from the concept of race.

As the poet said, "race is a myth, but racism isn't."