Answering a question from the Tuatara genome blog and starting a new series, Not Just DNA.
We are entering the age of the genome.
Our genomes tell us about ourselves. Genome sequences show our evolutionary relationships with other species. They reveal the origin and migration of humans. Unwelcome changes to our genomes can bring disability or illness; understanding genetic variation may bring personalised medicine. We can peer at the genetics of a yet-to-be-born child. DNA sequences are evidence for courtrooms and can track the source of an infectious disease outbreak.
But do we need to know more than the DNA sequence of a genome to understand it? It may be a question with a self-evident answer, but it’s important with so much effort being put into genome sequencing.
Plans are well advanced to sequence over a hundred thousand human genomes and the genomes of thousands of different species. Genomics England are set to sequence the genomes of 100,000 Brits over the next five years. (The 1000 genomes project was started in 2008 and published last year.) Personal genome sequencing is to found internationally. Genomes of individuals include an Australian aborigine, from various tribes in Africa, the southern tip of India and different Asian groups among many others including the Neanderthal genome. In New Zealand, we have a pilot project for the use of genomics in medical diagnosis. Organised efforts are working through a long list of species whose genomes are being sequenced: the Genome 10K project aims to sequence 10,000 vertebrates, roughly one for every vertebrate genus; the i5K initiative is to do the same for 5,000 insects and arthropods.
There are many more projects like this – and this is just the beginning. It’s much more that the human genome sequence and a few things that happened afterwards.
Knowing our genome
Our genomes are central to who we are and are often described as a blueprint for us.
A better description would be that our genomes code for a collection of parts that our biology can choose from to use to build us.
As our bodies grow, it’s the choice of what parts to use, when, and the interaction of those parts that make us.
Those interactions include interacting with the genome itself.
How do these bits used together to make us?
Does the DNA sequence by itself code for all of this?
Not just for our genomes, but also the genomes of the thousands of different species being sequenced.
“What about epigenetic markers? How important are these when considering if all the genomic information has been captured?”
The wider question is what makes a genome ‘work’?