Striatal dopamine transporter binding in Parkinson's disease associated with the LRRK2 Gly2019Ser mutation

We measured striatal dopamine transporter binding using [ ¹²³I]ioflupane and SPECT in patients with Parkinson's disease associated with the LRRK2 (PARK8) Gly2019Ser gene mutation (LRRK2-PD) and in gene-negative patients with idiopathic Parkinson's disease (IPD) of comparable disease duration and severity. The LRRK2-PD group consisted of a total of 10 patients (3 sporadic) with mean age 62 ± 14 years, disease duration 9 ± 3 years, and UPDRS III motor score 21.60 ± 6.65. The control IPD group consisted of 15 patients with mean age 59 ± 9 years, disease duration 9 ± 5 years, and UPDRS III motor score 23.80 ± 8.69. [ ¹²³I]ioflupane-specific uptake ratios were calculated for caudate nucleus and putamen using the occipital cortex as reference region. We found no differences between the LRRK2-PD group and IPD in all items studied. In particular, putamen and caudate uptake values as well as side asymmetry indexes and putamen/caudate ratios all revealed comparable between-group values. We conclude that in these patients carrying the LRRK2 Gly2019Ser mutation, the neurodegenerative process results in a pattern of nigrostriatal do-paminergic dysfunction similar to that observed in IPD.