1p36 deletion syndrome is one of the most common congenital genetic disorders present in nearly 1 in 5,000 births. 1p36 deletion syndrome can include the deletion of positive regulatory domain containing 16 (PRDM16), a transcription corregulator whose absence is strongly correlated in rodents and humans with cardiomyopathies.Without treatment cardiomyopathy leads to heart failure, however there is a stark difference between phenotypic outcomes when it comes to female and male patients: female patients experience earlier onset of and more aggressive cardiomyopathies with reduced survival rates. Our lab hypothesizes that the deletion of PRDM16 produces down-stream sex-specific patterns of replication stress and DNA damage during cardiac development that may significantly contribute to differences in cardiac function, and metabolic maturation leading to the phenotypic differences in cardiomyopathy. Our lab isolated and cultured neonatal rat ventricular cardiomyocytes and human myocytes to investigate PRDM16's role in cardiac development. To both of these cell strains, we observed sex segregated loss and gain of function with SiRNA and adenovirus. We will use western blots to analyze our collected cells with replication stress and DNA damage antibodies. We expect to see sex-specific patterns of replication stress and DNA damage in both the rat and human strains. The exploration of sex-differentiated cardiac maturation is imperative to understanding PRDM16's role in cardiac development and to develop precise therapeutics tailored to individual patients with 1p36 deletion syndrome.