Carney complex is a rare cardiocutaneous syndrome with an autosomal-dominant inheritance pattern. Apart from its cutaneous manifestations of multiple blue naevi and lentigines, it can involve multiple other organ systems, particularly the heart, where myxoma tumours commonly develop and can potentially lead to serious complications such as cerebrovascular accidents and myocardial infarction. Recently, a specific mutation in the gene encoding the R1-alpha regulatory subunit of cyclic adenosine monophosphate-dependent protein kinase A (PRKAR1alpha) has been discovered and found to be associated with a high risk of developing cardiac myxomas. We report the case of a Carney-complex family member who displayed no observable clinical or cardiac features of the disease but who was found to be positive for the PRKAR1alpha gene mutation on genetic testing. Further evaluation of this patient subsequently led to the discovery of a 3-cm atrial myxoma that had previously been undetected on cardiac assessment. This case highlights the potential benefits of using genetic screening for this disease.