Thread: DNA and genes

Are genes made of DNA or is it the other way round? I often get confused about this.
Is it that a chromosome is comprised of many DNA molecules and those ones which are located on the locus are the genes? I've heard that a gene is the 'long length of DNA'- What does this mean?

Thanks

Gene is a conceptual definition that often has as one of its components, a particular stretch of DNA.

Also, one chromosome is one long DNA molecule. Locus and gene have similar meanings, because they both define a specific area of the DNA molecule, as spurious said; but a gene codes for a protein, and a locus can be a protein-coding gene or a non-coding area of DNA.

Originally Posted by paralith

Also, one chromosome is one long DNA molecule. Locus and gene have similar meanings, because they both define a specific area of the DNA molecule, as spurious said; but a gene codes for a protein, and a locus can be a protein-coding gene or a non-coding area of DNA.

I always thought of a locus as a specific location on a chromosome, and a gene as a stretch which contains a protein-coding region as well as it's immediate regulatory sequences.

Originally Posted by i_feel_tiredsleepy

Originally Posted by paralith

Also, one chromosome is one long DNA molecule. Locus and gene have similar meanings, because they both define a specific area of the DNA molecule, as spurious said; but a gene codes for a protein, and a locus can be a protein-coding gene or a non-coding area of DNA.

I always thought of a locus as a specific location on a chromosome, and a gene as a stretch which contains a protein-coding region as well as it's immediate regulatory sequences.

...yes, but I don't see how that's different from what I said. 0_o You could say a gene is a type of locus.

Originally Posted by paralith

Originally Posted by i_feel_tiredsleepy

Originally Posted by paralith

Also, one chromosome is one long DNA molecule. Locus and gene have similar meanings, because they both define a specific area of the DNA molecule, as spurious said; but a gene codes for a protein, and a locus can be a protein-coding gene or a non-coding area of DNA.

I always thought of a locus as a specific location on a chromosome, and a gene as a stretch which contains a protein-coding region as well as it's immediate regulatory sequences.

...yes, but I don't see how that's different from what I said. 0_o You could say a gene is a type of locus.

It wasn't different, I was just trying to conceptualize it in a clearer way.

And ya genes are loci.

How come people speak of genes for homosexuality then?

Clearly that definition doesn't fit within the classical one just mentioned.

isn't that reporter-shorthand for "i don't know what causes homosexuality, but i've heard that a genetic component features as part of the explanation" ?
they probably couldn't care less what exactly a gene is, apart from the latest buzzword when reporting science

Well, reporters heard it from 'scientists'.

There have been several studies that have identified specific areas on certain chromosomes that display extremely high degrees of linkage with certain cases of male homosexuality. No single gene has been identified (one such identified region on Xq28 is large enough to contain several hundred genes), and even when one or two genes are identified in the future, exactly how and to what degree they contribute to homosexuality is another question entirely. Given that it's a complex behavioral trait there are probably many genes whose products and interactions all in some way contribute.

yes, that is your opinion. That doesn't change the fact that these people see genes differently.

Originally Posted by spuriousmonkey

yes, that is your opinion. That doesn't change the fact that these people see genes differently.

....I know. But you did say that "these people" got their information from scientists and I wanted to defend those scientists position. They're not the ones who twisted the information. The media went crazy after this study came out and proclaimed that "the gay gene" had been found, etc etc, even though that's a completely incorrect interpretation. Apparently the primary author even got a phone call from a man wanting to make sure it wasn't HIS fault that his son was gay, since this supposed gene was located on the X chromosome.

I don't actually think these scientists have a different position on the definition of gene than the reporters who parrot their viewpoints.