IDH1 and glioma: In a study by Krutz et al., the patients with high-grade gliomas were stratified as High-HRD (>5% LOH or >3% LOH) and Low-HRD (<5% LOH or <3% LOH), and used the Kaplan–Meier method to assess OS and PFS, with a weak association between LOH score and IDH status (p = 0.09) [27].