Table 2

 Frequency of the G2019S mutation according to familial aggregation

Proband categoryn (%)Male/femaleOnset (years) (mean (SD))RangeG2019S%
*p<0.002 v the frequency among the 452 sporadic probands (Fisher exact test).
†p<0.025: frequency in familial v sporadic early onset probands.
‡p = 0.05: frequency in familial v sporadic late onset probands.
§p<0.001 v the frequency among the 452 sporadic probands.
NSNo significant difference compared with the frequency among the 452 sporadic probands.
None of the differences between early onset and late onset groups (familial, sporadic, or all) was statistically significant.
PD, Parkinson’s disease.
All probands (early and late onset)629 (100%)369/26052.7 (10.9)23 to 82132.1%
All familial probands (1st, 2nd, 3rd degree affected relatives)177 (28.1%)103/7452.6 (10.9)23 to 8295.1%*
All sporadic probands452 (71.9%)266/18652.7 (11.0)23 to 8040.9%
All early onset probands230 (100%)149/8140.8 (5.6)23 to 4973.0%
Familial early onset68 (29.6%)43/2541.5 (5.5)23 to 4957.4%†
Sporadic early onset162 (70.4%)106/5640.6 (5.7)23 to 4921.2%
All late onset probands399 (100%)220/17959.5 (6.6)50 to 8261.5%
Familial late onset109 (27.3%)60/4959.6 (6.9)50 to 8243.7%‡
Sporadic late onset290 (72.7%)160/13059.4 (6.5)50 to 8020.7%
Probands with “dominant” PD (1st or 2nd degree affected relatives)11468/4650.1 (10.7)23 to 7487.0%§
    Probands with one affected parent6942/2751.0 (9.7)23 to 7168.7%§
    Probands with affected 2nd degree relative only4224/1849.2 (11.7)32 to 7424.8%NS
    Probands with affected siblings and 2nd degree relative32/141.0 (15.6)32 to 590
Probands with affected siblings only4927/2256.9 (10.5)36 to 8212.0%NS
Probands with affected 3rd degree relative only147/758.1 (6.9)57 to 650