Investigating genetic link with premature heart disease for Peoples of Fiji living in New Zealand

Published: 27 September 2023

Dr Pritika Narayan will investigate a striking pattern of premature heart disease across consecutive generations of selected families with ancestry linked to the Fiji Islands and explore a possible genetic cause, as part of a three-year research project and fellowship awarded by the Heart Foundation.

In New Zealand, preliminary findings suggest a high rate of heart events experienced by Peoples of Fiji – individuals who identify as Fijian, Fijian Indian, or Indian born in Fiji.

The Heart Foundation is funding a world-first study, led by University of Otago researcher Dr Pritika Narayan, that will examine the relationship between genetics, clinical features and outcomes for Peoples of Fiji living in New Zealand who have experienced a life-threatening premature heart event.

Dr Narayan has been awarded a three-year Project Grant and a Research Fellowship to develop a community-led framework for the research in collaboration with the Fijian community in New Zealand. She will then investigate genetic drivers in the most severe and premature cases of heart disease within this group.

"The pattern of inheritance in some families from Fiji is striking, with consecutive generations experiencing a disproportionately high rate of heart attacks and heart disease, and at an earlier age," explains Pritika. "However, the genomes of affected individuals have not been examined to date."

These families have had several generations experiencing earlier onset heart disease – for example, a grandfather having a heart attack in his 60s, his son in his 40s, and his grandson in his 20s.

"The ability to understand genetic drivers of heart disease for ethnic minority groups could have an unprecedented impact," says Pritika. "Not just for affected or at-risk families in New Zealand and Fiji, but for other ethnic communities worldwide."

A co-design community-led study

Pritika is working closely with the community from Fiji across New Zealand who will help co-design the study framework. "The community-led approach is inspiring and I find it energising," shares Pritika.

The first step is developing community-led guiding principles for the research which will ensure the study is culturally informed and keeps research participants and their data safe.

Running community events and talanoa sessions will continue throughout the study. These raise awareness of both the research and heart disease risk, especially in relation to ethnicity.

Potential genetic link

The hereditary pattern of premature heart disease among affected families across several generations points to genetic factors. These genetic factors may have either an independent risk or an additive effect on heart disease risk when combined with factors such as diet or lifestyle.

The second part of the research will look at individuals with the most severe and premature heart disease. This looks for a unique signature in a single gene, which may be inherited across generations of a family. The research will study 40 affected individuals in great detail. An international team with the necessary genetic expertise will be part of this collaboration.

Benefits for ethnic groups

Pritika is elated that with Heart Foundation funding this research can now begin to potentially inform gene-based improvements in screening, diagnosis and treatment strategies for current and future generations of Peoples of Fiji living in New Zealand.

The research focuses on genetic variants linked to premature heart disease in an under-studied group – Peoples of Fiji – but it has the potential to directly impact clinical care and prevention strategies offered to other ethnic minority groups, especially 11 million Melanesian people living in the Pacific and 25% of the global population who are South Asian.

Revealing a genetic basis could lead to novel pathways for drug discovery with global benefits, especially for other indigenous communities. Many medications are currently designed for a European population and may not be optimised for ethnic groups.

"Gene-based targets have the potential to aid early screening within affected families, improve disease stratification and prevention, and enhance equity in the development of genome-based medicine and drug discovery for ethnic minority groups," says Pritika.

Personal impact of premature heart disease

Being born in Fiji and experiencing premature heart-related deaths in her family and community has shaped Pritika's career direction.

When she began researching this, she was shocked to find a lack of genetic heart studies in Peoples of Fiji with the majority of the genetic information about premature heart disease from people with European ancestry.

"I'm immensely grateful to the Heart Foundation for supporting this valuable research for the next three years," says Pritika.