New gene variations linked to cholesterol levels
Tue, 9th Dec 2008
It’s becoming increasingly clear that our genes play a big role in our health. In some cases, people carry major gene faults that can significantly increase their risk of certain diseases, such as cancer. But now we’re starting to focus on subtle genetic variations that can increase or decrease risk of various illnesses.
Now an international research team has found 11 new regions of genetic variation that are linked to levels of cholesterol and triglycerides – both of which are important in heart and cardiovascular disease. Added to previous research, this means that we now know about 30 such gene variations. And although major faults in some of the genes can lead to serious metabolic problems, and diseases such as type 2 diabetes, it’s likely that less serious faults could act to subtly increase a person’s risk of heart disease.
To start with, the researchers looked at the results of 7 studies that had screened across the whole genome for genes linked to cholesterol and triglyceride levels. Then the researchers looked at DNA samples from over 20,000 people, and found 30 gene sites. This included 19 that had been spotted before, but 11 new ones too. Although some of these new genes have previously been linked to cholesterol problems, or diabetes, many of them are enigmatic, and it’s not clear how they’re working. So lots more work to do.
This will also be important when finding new drugs. The more we understand about the genetic faults and variations that underpin diseases, the more likely we are to be able to design more targeted, effective treatments. For example, statin drugs work by blocking the actions of a gene called HMGCR – one of the 30 gene variations I mentioned earlier. We’ve all heard about the effectiveness of statins for treating cardiovascular problems, and the researchers are hopeful that some of these new genes will also be good targets.
The researchers think that these 30 genes account for about a fifth of the genetic contribution to cholesterol and triglyceride levels, so there’s many more genes out there that we don’t yet know about. These could be tracked down by doing large studies in a broader range of ethnic backgrounds. And it’s also going to be important to sequence these 30 genes in great detail, to pinpoint the exact differences that are responsible. This could lead to screening tests to find people at high risk – for example those who have a lot of heart disease in the family – who could be offered preventative treatment.