Josephine Chetty was only 19 when she was detected with a block in her heart, in 2008. The Malad resident underwent an angioplasty at Nair hospital four months ago.
A heart block at such a young age is rare and Chetty's case left doctors at PD Hinduja Hospital, Mahim, intrigued. In 2008, the hospital started a study on genetic mutations in patients that lead to low levels of high density lipoprotein (HDL), known as good cholesterol. Low HDL level is a strong independent indicator of possible heart disease.
When doctors studied Chetty's blood samples, they found that her level of good cholesterol was abysmally low. The HDL level in her blood was 19 miligram/decilitre, when the required level should be higher than 40 mg/dL. Her blood sample showed five gene mutations, which doctors suspect had led to low HDL levels.
Three years on, doctors at Hinduja hospital have identified 40 types of gene mutations in Indians who have low levels of good cholesterol. The timely identification of genetic mutations could help preempt possible heart diseases in people who fall in the high-risk category, such as those with a family history of heart ailments, said Dr TF Ashavaid, head of department of laboratory medicine, Hinduja hospital, on the eve of World Heart Day, which falls on Thursday.
While Indians are known to be genetically pre-disposed to heart disease, little research has as yet been done on the subject. Dr Ashavaid, who conducted the study along with her student, Apurva Sawant, who is pursuing a PhD, said theirs is the first study that focuses on the Indian population.
The study, which was completed in March, has not yet been published.
Till now only five mutations of genes had been known to cause low HDL, going by studies conducted in the US and Europe. "The 40 mutations identified by us have not been found in populations in other countries. We need to conduct further studies to confirm whether all these genetic mutations cause low HDL," said Dr Ashavaid.
"If the genes are responsible for the low levels of HDL in the body, any amount of exercise [advised when a person has low HDL] will not help the patient; he has to be prescribed drugs. The study will help us identify such patients," the doctor said.
Reacting to the findings, Dr BK Goyal, consulting cardiologist at Bombay hospital, said: "It is an established fact that low HDL increases the risk of heart disease. I am not aware of this study, but it may help predict heart disease. However, from experience, I believe that people can win over their genetic inhibitions provided they lead a healthy lifestyle."