in October, 2015, the BBC incorrectly reported the discovery of a new gene which puts women at higher risk of heart disease.
The study in question did not find a new gene. Rather, a switch in one of the building blocks of DNA present in some women is associated with a reduced risk of cardiovascular disease.
The switch occurs in two of the building blocks — guanosine and adenosine — at a single point on chromosome 16, and may be responsible for the protective benefit which has been shown only in women, not men.
The “switch” has a name: rs4888378, and is a variation on the DNA strand, not a separate gene. This switch is called a single nucleotide polymorphism. Here’s how the National Library of Medicine of the NIH describes it:
“All humans share a very high level of similarity in their DNA sequence, particularly within genes, where the sequence of nucleotides contains the instructions for making the proteins that the cell and organism need. However, there are points in the DNA where different people have a different nucleotide, these are called single nucleotide polymorphisms (SNPs, pronounced 'snips')." (1)
Researchers believe this SNP positively affects a gene we all have — BCAR1.
According to Pubmed, "the BCAR1 gene is present in both men and women, and has many 'healthy' functions. It is often reported in the media because certain genetic variations in this gene increase the risk of breast cancer."
Note, BCAR1 is not the same gene as BRCA1.
The following are risk factors for CVD:
- High blood pressure
- Type 2 diabetes
- Smoking
- High cholesterol
- Poor diet
- Lack of physical exercise
- Being overweight or obese
Women in the early stages of CVD often show no symptoms. An ultrasound of the carotid arteries of the neck can reveal a thickening of the artery walls associated with CVD. Women who had adenosine on both strands of the SNP variations had 20 percent slower thickening of the carotid arteries each year .(2)
Whatever your DNA, reduce your risk of heart disease. Quit smoking, exercise, and eat a diet rich in fruits and vegetables. And remember heart attack symptoms in women are often unrelated to chest pain. (3)
Symptoms of heart attack in women are more likely to include:
- Neck, jaw, shoulder, upper back or abdominal discomfort
- Shortness of breath
- Right arm pain
- Nausea or vomiting
- Sweating
- Lightheadedness or dizziness
- Unusual fatigue
If you are experiencing any of these symptoms, contact your doctor immediately.
Sources:
1) Health news glossary. NHS.uk. Retrieved November 22, 2015.
http://www.nhs.uk/news/Pages/Newsglossary.aspx#snp
2) Genetic variation 'reduces risk of heart disease in women’. NCBI.org. Retrieved November 22, 2015.
http://www.ncbi.nlm.nih.gov/pubmedhealth/behindtheheadlines/news/2015-10-22-genetic-variation-reduces-risk-of-heart-disease-in-women
3) Heart disease in women: Understand symptoms and risk factors. WebMd.com. Retrieved November 23, 2015.
http://www.mayoclinic.org/diseases-conditions/heart-disease/in-depth/heart-disease/art-20046167
Reviewed November 23, 2015
by Michele Blacksberg RN
Edited by Jody Smith