The genetic underpinnings of myeloid neoplasms are becoming increasingly well understood. The accessibility to sequencing technology, in particular next-generation sequencing (NGS), has highlighted the importance of gene mutations in myelodysplastic syndromes (MDS) in conjunction with traditional cytogenetics. With the relatively recent influx of molecular information to complement known cytogenetic abnormalities, the diagnosis, classification, and prognosis of MDS and acute myeloid leukemia (AML) have been increasingly refined, which has also led to therapeutic advancements. It has been shown that TP53 mutations have a significant impact in cases of MDS, as well as AML, and have led to TP53-defined myeloid disease. TP53 mutations are also now incorporated into prognostic scoring systems, as patients have been shown to have aggressive disease and poor outcomes. With the increased understanding of the importance of TP53 disruption in myeloid neoplasia, it is likely that the critical role of TP53 will continue to be highlighted by an individual's disease classification and personalized therapeutic management.