Analysis of parkin gene mutations in Han Chinese with sporadic early-onset parkinsonism in southern China / 中华神经科杂志

ABSTRACT

Objective To investigate the spectrum and features of parkin gene mutations in Chinese patients with sporadic early-onset Parkinsonism (EOP) in southern China.Methods All 156 Han Chinese patients with sporadic EOP were screened for mutations in parkin gene using SYBR Green Ⅰ Real-time PGR combined with sequencing of the entire coding region of the gene.Results Nineteen cases carried parkin mutations, including 2 homozygous, 2 compound heterozygous and 15 heterozygous mutations.Seventeen parkin gene rearrangement mutations ( 12 exon deletions and 5 exon duplications) and three small sequence mutations (ⅣS9 + 18C ＞ T,c.202-203delAG and c.813delT) were identified.The c.813delT is a novel mutation.The segment between exon 1 and 7 are mutational hot spot.Cases with parkin mutations showed no difference in initial symptoms, cardinal symptoms and disease severity, compared with cases without parkin mutations.But patients with parkin mutations showed significant earlier onset age ( ( 40.9 ± 6.8 ) years vs (35.5 ± 10.0) years, Z = -2.271, P ＜0.05) and longer disease duration ( (4.4 ±3.6) years vs (7.6 ±4.0) years,Z = - 3.680, P ＜ 0.05 ) than those without parkin mutation.Conclusions The frequency of parkin gene mutation was 12.18% in Han Chinese patients with sporadic EOP.Rearrangement mutation may be the predominant type of mutations.The exon deletion is a main mutation style.The sequence fragment between exon 1 and 7 of the parkin gene are mutational hot spots.There were no significant differences in clinical features between cases with parkin mutation and those without.However, our patient with parkin mutations showed a significantly earlier onset age, longer disease duration and slower progression than those without parkin mutation.