Owing to insufficient reliable olfactory data in the QSBB series, we were unable to make comparisons; however, to detect anosmia in only 51% of patients with mutations in LRRK2 is unexpectedly low when olfactory dysfunction is reported in 80–100% of patients with idiopathic PD.8, 24. This evidence concerns the gene LRRK2 and Kallmann syndrome.