Genome Question

[Iosens]

Hi

 

new to the forum

 

one thing that I always wonder about is the exact definition of "Genome".

 

What is the "Human Genome". If you sequence a woman from Norway she will not have the same genes as a Aborigine man in Australia.

 

What parts count as the "Human genome" - or the genome of a bacteria- , when mutations are all over the place?

 

Thanks for enlightening me!

[CharonY]

The genome is defined as the complete set of all the genetic information withing a given cell. This includes the chromosome as well as extrachromsomal structures such as e.g. plasmids. Extending the use to the species level (i.e. human genome) is generally only used to contrast it with a different species. Usually higher-level features are discussed rather than differences on the base-pair level.

 

Note that the woman from Norway will have the same genes as an Australian Aborigiene. There are going to be allele variants, however. The same could be said, when sequencing and comparing two Norwegians.

 

Again, the genome can be used on several levels, down to the exact base composition (e.g. when reporting the genome of a particular cell strain) but also in a more abstract sense. Context is important to figure out whether the genetic composition of individuals or groups are being discussed.

Edited October 24, 2012 by CharonY

[Iosens]

Thanks

 

are you saying that the genome only looks at the presence of "genes", like the gene for a hair color, rather that the differences of a black haired person compared to a blond person?

[CharonY]

No, genome refers to all the genetic information, not only to genes. It also includes intergenic regions (with or without regulatory functions) as well as potential open reading frames or genes with unknown functions, etc.

 

What you refer to are differences on the sub-gene level, i.e. allele differences. Alleles are varieties of the same gene, not different ones.