Offering healthy people genetic screening could provide clinically important information in over 15 percent of cases.
Researchers from the USA, Canada and Singapore offered proactive screening to adult participants through local primary and specialist healthcare facilities. The samples were screened for variants known or believed to be pathogenic in 147 different genes associated with a range of medical conditions including cancers and cardiovascular disease.
The researchers wrote that their data 'provide a foundation for further studies to assess the role of genetic screening, as part of regular medical care, in reducing morbidity and mortality from actionable genetic disorders and to determine its clinical utility and cost-effectiveness.'
The variants being screened for were all monogenic, actionable variants. An actionable gene is one with consequences that healthcare professionals understand and can act upon. In many cases, knowing that a person has such a variant can help reduce the risk of being affected or the severity of disease through proactive screening, lifestyle changes or medication.
Almost 10,500 accepted the test, of whom 1619 (15.5 percent) had at least one gene variant conferring increased risk. Of these, 138 people (1.3 percent of the whole group) had two or more such variants.
Variants associated with cancers were found in 807 participants: genes linked to colorectal cancer were most common, followed by breast and ovarian cancers and melanoma. Six hundred and eight people had variants in genes associated with cardiovascular disease, including heart problems such as arrhythmias and cardiomyopathies, familial hypercholesterolaemia and hereditary thrombophilia.
Forty-nine participants had variants that put them at risk of serious conditions including hereditary cancers, cardiovascular disorders, or malignant hyperthermia susceptibility. The findings were published in BMC Medicine.
Currently, genetic testing for healthy people is generally limited to the blood spot test for newborns and looking for specific conditions in people where there is a known family history.