Table 4. Comparative meta-analysis of the associations of the selected compound genotypes with Alzheimer’s disease (AD) Aβ42 and tau biomarkers.

Biomarker	Source	Genotype	N	Beta	SE	P value	Direction
Aβ42	CSF	111+222	178	-0.054	0.062	3.77E-01	−−????
Aβ42	CSF	1XY+2XY	242	-0.091	0.060	1.32E-01	−−????
Aβ42	CSF	100+200	56	Reference
Aβ42	Plasma	111+222	1462	0.619	0.569	2.77E-01	−?++++
Aβ42	Plasma	1XY+2XY	1821	0.509	0.553	3.57E-01	−?++++
Aβ42	Plasma	100+200	396	Reference
Tau	CSF	111+222	189	0.066	0.057	2.46E-01	++????
Tau	CSF	1XY+2XY	253	0.060	0.054	2.70E-01	++????
Tau	CSF	100+200	56	Reference
Tau	Plasma	111+222	1033	0.033	0.021	1.25E-01	+?+++?
Tau	Plasma	1XY+2XY	1280	0.047	0.021	2.27E-02	+?+++?
Tau	Plasma	100+200	289	Reference

Column “Genotype” shows compound genotypes encoded by triples of numbers and X and Y letters; these notations are detailed in Table 3 footnote. Column “Direction” shows sign of the effect beta in individual studies in the same order as in Table 3. A gamma general linear model with a log link function was used for all biomarkers except Aβ42 measured in plasma. SE denotes standard error. CSF denotes cerebrospinal fluid. More details with individual-study estimates are given Supplementary Table 6.