TAFAZZIN and cardiomyopathy: TAZ gene sequencing can be targeted selectively to those with an abnormal cardiolipin ratio test or performed in all candidate patients where cardiolipin testing is not available. It is increasingly being offered as one of the genes sequenced simultaneously in sequencing panels for investigation of cardiomyopathy. It also has an important place in the investigation of patients/families where appropriate samples for biochemical testing are not available from suspected index patients.