Table 1.
Characteristics of Families With LOAD Included in the Genomewide Scan
| Family-Based Analyses |
Case-Control Analyses |
||
|---|---|---|---|
| Individuals or Families (n=1902 Individuals or 328 Families) | Patientsa (n=328) | Controls (n=236) | |
| Alzheimer disease, No. (%)b or No. | |||
| Broad definitionc | 776 (40.8) | 320 | NA |
| Narrow definitiond | 665 (34.9) | 319 | NA |
| Unaffected | 873 (45.9) | NA | 237 |
| Unknown | 253 (13.3) | NA | NA |
| Mean (SD) age at onset, ye | 73.9 (7.5) | 73.3 (7.1) | 78.1 (9.1) |
| Mean (SD) No. of patients per family | 2.4 (0.68) | NA | NA |
| Affected persons per family, No. (%)f | |||
| ≥5 | 6 (1.8) | NA | NA |
| 4 | 16 (4.9) | NA | NA |
| 3 | 69 (21) | NA | NA |
| 2 | 237 (72.3) | NA | NA |
| Women, No. (%) | 1183 (62.2)b | 203 (61.9) | 138 (58.5) |
| APOE allele frequency, % | |||
| ε4 | 30.9 | 43.1 | 9.5 |
| ε3 | 65.5 | 53.7 | 80.7 |
| ε2 | 3.5 | 3.2 | 9.8 |
Abbreviations: APOE, apolipoprotein E gene; LOAD, late-onset Alzheimer disease; NA, not applicable.
a
One patient from each family was chosen as the case for the case-control analysis. In most instances, this was the proband.
b
Based on a total of 1902 individuals.
c
Includes possible, probable, and definite LOAD.
d
For linkage analyses including the narrow definition of affected (ie, probable and definite LOAD), individuals with possible LOAD were reclassified as unknown.
e
For the case-control data set, age at the last evaluation is presented.
f
Based on a total of 328 families.