BRCA1 and hypoparathyroidism-retardation-dysmorphism syndrome: Recently, in a WES/WGS study of 11 chordoma patients, Gröschel et al. demonstrated that SBS3, a mutational signature associated with homologous recombination deficiency (HRD) and BRCA1/2 germline mutations, was significantly enriched in advanced chordoma samples, thus implicating the poly(ADP-ribose) polymerase (PARP) inhibitor as a promising therapeutic option34.