Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Supplementary Material for: APOE*E2 Allele Delays Age of Onset in PSEN1 E280A Alzheimer’s Disease JI Vélez1,2,*, F Lopera2,*, D Sepulveda-Falla2,3,*, HR Patel1, AS Johar1, A Chuah4, C Tobón2, D Rivera2, A Villegas2, Y Cai1, K Peng5, R Arkell6, FX Castellanos7, SJ Andrews9, MF Silva Lara1, PK Creagh1, S Easteal9, J de Leon8, ML Wong10, J Licinio10*, CA Mastronardi1,10*& M Arcos-Burgos1,2,*,# 1. Genomics and Predictive Medicine Group, Department of Genome Sciences, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia. 2. Neuroscience Research Group, University of Antioquia, Medellín, Colombia. 3. Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. 4. Genome Discovery Unit, Department of Genome Sciences, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia. 5. Biomolecular Resource Facility, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia. 6. Early Mammalian Development Laboratory, Research School of Biology, The Australian National University, Canberra, ACT, Australia. 7. NYU Child Study Center, NYU Langone Medical Center, New York, NY, US, and Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, US. 8. Mental Health Research Center at Eastern State Hospital, University of Kentucky, Lexington, Kentucky, US. 9. Genome Diversity and Health Group, Department of Genome Sciences, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia. 10. South Australian Health and Medical Research Institute and Department of Psychiatry, School of Medicine, Flinders University, Adelaide, Australia. * These authors contributed equally to this work. # Correspondence to be directed to: Mauricio Arcos-Burgos, M.D., Ph.D. Associate Professor and Group Leader, Genomics and Predictive Medicine Group John Curtin School of Medical Research, The Australian National University, Building 131 Garran Road, Canberra, ACT, Australia. E-mail: Mauricio.Arcos-Burgos@anu.edu.au 1 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Clinical assessment: The modified CERAD evaluation battery As part of our clinical program of AD, patients as well as carriers and non-carriers family members (either from the same geographical region as the E280A pedigree or carrying the PSEN1 E280A mutation) underwent clinical, neurological and neuropsychological assessment at the Group of Neurosciences AD Clinic. Patients were defined as affected by MCI based on Petersen’s criteria, by AD if the DSM-IV criteria were met, 1, 2 and using a Spanish version of the CERAD evaluation battery3 adapted for the cultural and linguistic characteristics specific to this population,4-7 which includes the following measures: (i) Semantic Fluency (Animal Naming): Individuals are requested to name as many animals as they can in 1 min. The dependent variable is the number of unique animals named. (ii) Modified Boston Naming Test: Consists in asking individuals to identify 15 line drawings of increasing complexity (high, medium and low frequency) with a maximum of 10 s for each drawing. One point is awarded for each correct response. The dependent variable is the total number of correct naming. (iii) Mini-mental State Exam (MMSE): A modified version of the MMSE by Folstein (1975)8 was used. The spelling backward subtest was excluded because the spelling ability involved in this task is not a common skill for Spanish-speaking people. Instead, we replaced it with subtraction by threes, which is more appropriate for this population. The total score of this test was 30 points. The dependent variable was the total number of correct points. (iv) Word List Memory (WLM): This test assesses the ability to recall newly learned information. Individuals are presented 10 printed words on a card at the rate of one every 2 s. They are immediately asked to recall as many words as possible from the list. This procedure is repeated in three consecutive trials. The maximum number of correct words is 30 for the three trials. The number of correct words identified serves as the dependent variable. 2 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 (v) Constructional Praxis: Individuals are presented with four line drawings of figures of increasing complexity (circle, rhombus, pentagon and cube), one at a time, and asked to copy them. Maximum time allowed for copying each figure is 2 min. Reproductions are scored according to predetermined criteria and the dependent measure is the total score for the four drawings. (vi) Word List Recall: This test assesses delayed memory by requesting individuals to recall the list of ten words presented in the WLM task. The maximum time allowed for this recall is 90 s. One point is awarded for each word recalled correctly with maximum of 10 points if all the words are recalled. (vii) Word List Recognition. This test consists of recognition of the 10 words from the WLM task, presented in a list of 20 words (including 10 additional distractor words). A forced-choice paradigm is used so that subjects must respond with YES to the words they consider correct (i.e., in the list of words previously read), and NO to the words that were not on that list. One point is awarded for each word correctly recognized. To adjust by chance, the subject’s score is calculated as the total number of correct answers minus 10; if the result is less than 0, a score of 0 is given. (viii) Line-Drawing Recall. Individuals are asked to recall the drawings they copied previously and draw them from free recall on a blank sheet of paper. This tests serves to assess visual memory. 3 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 b 70 AOO (years) a 60 50 40 35 45 50 55 60 AOO (years) 65 70 Female Male Gender d 70 70 AOO (years) AOO (years) c 40 60 50 40 60 50 40 None Elementary High Tertiary 0 Education 5 10 15 20 Schooling (years) Supplementary Figure 1. (a) Histogram and probability density plots for the ADAOO in 71 patients with PSEN1 E280A AD. Analysis of the ADAOO distribution disclosed the presence of two hidden groups with an average ADAOO of ~45 and ~57 years old, respectively. Box- and violin-plots for the ADAOO by (b) gender and (c) education group. No difference in the average ADAOO was found in either case. (d) ADAOO as a function of the years of education. ADAOO. AD = Alzheimer’s disease; ADAOO = Alzheimer’s disease age of onset. 4 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 b 80 AOO (years) a 70 60 50 40 40 70 80 Female Male Gender d 80 70 80 AOO (years) AOO (years) c 50 60 AOO (years) 60 50 70 60 50 40 40 Elementary High 0 Tertiary 5 10 15 20 Schooling (years) Education Supplementary Figure 2. (a) Histogram and probability density plots for the ADAOO in Results 54 patients with sporadic AD. Analysis of the ADAOO distribution disclosed the presence of two hidden groups with an average ADAOO of ~59 years and ~69 years, respectively. Box- and violin-plots for the ADAOO by (b) gender and (c) education group. No difference in the average ADAOO was found in either case. (d) ADAOO as a function of the years of education. Observe that individuals with < 3 years of education in the sample seem to have an earlier ADAOO. AD = Alzheimer’s disease; ADAOO = Alzheimer’s disease age of onset. 5 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Supplementary Figure 3. (a) Partition of phenotypic variance in the multi-locus LMEM for each forward inclusion (steps 1 to 10) and backward elimination (10 steps after the dotted line). The yellow vertical line marks the selected model based on the highest multiple posterior probability of association (mPPA). (b) Manhattan plot for the CEFVs included for analysis. Markers with –log10(P)>5.08 were significant after FDR correction. The red horizontal line corresponds to the Bonferroni threshold of – log10(P)=6.89. (c) Beanplots for the ADAOO in variants with PFDR<0.05 (see Table 1). Pink, blue and dotted horizontal lines correspond, respectively, to the within genotype average ADAOO, the individuals’ ADAOO and the global average ADAOO in our 71 patients with PSEN1 E280A Alzheimer’s disease. ADAOO: Alzheimer’s disease age of onset. CEFVs: common exonic functional variants. LMEM: linear mixed-effects model. 6 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Rare Functional Exonic Variants Modifying ADAOO Supplementary Table 1. Results for the association analysis of rare variants using (a) regression- and (b) permutation-based KBAC. (c) Top 20 genes associated genes from the SKAT-O9 analysis of rare variants. (a) Chr 5 11 10 Start 31,799,031 108,093,559 98,741,041 Stop 32,111,038 108,239,826 98,745,585 Gene PDZD2 ATM C10orf12 m 7 4 3 G 8 5 4 T 3.395 2.423 1.817 P 1.80x10-2 2.40x10-2 5.00x10-2 (b) Chr 5 11 17 Start 31,799,031 108,093,559 71,330,523 Stop 32,111,038 108,239,826 71,640,227 Gene PDZD2 ATM SDK2 m 7 4 3 G 8 5 4 T 0.200 0.143 0.107 P 1.40x10-2 2.13x10-2 5.29x10-2 Gene m ATM 4 PDZD2 7 RSPH6A 3 ADSSL1 3 ZNF311 3 FNDC7 3 VILL 3 XKR9 3 PLG 3 LMOD3 3 TEX35 3 ZNF646 3 CDC42BPG 3 PACS2 3 INCENP 3 C10orf12 3 SCN10A 3 SDK2 3 ERMARD 3 T 0.004 0.005 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 0.011 P 6.94x10-3 9.15x10-3 1.95x10-2 1.95x10-2 1.96x10-2 1.96x10-2 1.96x10-2 1.97x10-2 1.97x10-2 1.97x10-2 1.97x10-2 1.97x10-2 1.98x10-2 1.98x10-2 1.98x10-2 1.98x10-2 1.98x10-2 1.98x10-2 1.9x10-2 (c) Chr 11 5 19 14 6 1 3 8 6 3 1 16 11 14 11 10 3 17 6 Start 108,093,559 31,799,031 46,298,968 105,190,534 28,962,594 109,255,556 38,035,078 71,581,600 161,123,225 69,156,039 178,482,212 31,085,743 64,591,662 105,767,148 61,891,445 98,741,041 38,738,837 71,330,523 170,151,718 Stop 108,239,826 32,111,038 46,318,605 105,213,647 28,973,037 109,285,367 38,048,676 71,648,177 161,175,085 69,171,746 178,492,635 31,094,833 64,612,041 105,864,484 61,920,635 98,745,585 38,835,501 71,640,227 170,181,680 Chr: Chromosome; m: number of markers; G: number of multi-marker genotypes; T: one-side KBAC test statistic; P: one-sided P-value; KBAC: Kernel-based adaptive cluster; SKAT-O: Optimized Sequence Kernel Association Test. Highlighted genes in (c) were also found using KBAC. 7 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Supplementary Table 2. GO process and disease annotations for the network involving AOO modifier genes. GO Processes and Disease Annotations (P-value) Gene(s) involved PSEN1 APOE* TRIM22 IFI16 RC3H1* DFAN5 GO Process Negative regulation of cell proliferation (3.367x10-7) Cell differentiation (1.4x10-5) Regulation of apoptotic process (2.69x10-5) Positive regulation of apoptotic process (1.57x10-3) Regulation of neuron apoptotic process (2.37x10-4) Regulation of intrinsic apoptotic signalling pathway (2.68x10-4) Intrinsic apoptotic signalling pathway by p53 class mediator (2.96x10-4) Negative regulation of neuron death (5.22x10-3) Positive regulation of IL-1 β production (7.56x10-5) Immune response (2.32x10-4) T cell activation involved in immune response (4.30x10-4) Positive regulation of NIK/NK-kappa B signaling (1.66x10-3) Diseases Alzheimer's disease (3.34x10-5) EOAD (1.68x10-2) Delerium, Dementia, Amnestic, Cognitive disorders (3.13x10-5) Frontotemporal lobar degeneration (4.3x10-4) Frontotemporal lobar dementia (4.3x10-4) Neurodegenerative diseases (5.85x10-4) * Age of onset decelerators. Conventions Apoptotic-related processes Immunological-related processes 0 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Supplementary Table 3. GO process and disease annotations for the network involving AOO modifier genes. Genes involved (by Network Analysis) PSEN1, APOE PSEN1, RC3H1 IFI16, RC3H1 IFI16, PSEN1 IFI16, PSEN1, RC3H1 IFI16, PSEN1 Processes Organic hydroxy compound transport Positive regulation of protein catabolic process Regulation of axonogenesis Positive regulation of proteolysis Regulation of coagulation Positive regulation of protein processing Regulation of synaptic plasticity Positive regulation of cellular catabolic process T cell activation involved in immune response Lymphocyte activation involved in immune response Cell activation involved in immune response Leukocyte activation involved in immune response Negative regulation of B cell proliferation Myeloid leukocyte differentiation Leukocyte differentiation Autophagy Cellular response to starvation Antigen receptor-mediated signaling pathway Immune effector process Positive regulation of intracellular signal transduction Regulation of intracellular signal transduction Negative regulation of response to stimulus Regulation of signal transduction IFI16, PSEN1, RC3H1, TRIM22 PSEN1, RC3H1, TRIM22, DFNA5 PSEN1, RC3H1, APOE, TRIM22, DFNA5 IFI16, AOAH, PSEN1, RC3H1, APOE, FCRL5 PSEN1, RC3H1, APOE, FCRL5, TRIM22, DFNA5 IFI16, AOAH, PSEN1, RC3H1, APOE, FCRL5, TRIM22, Regulation of response to stimulus DFNA5 1 P PFDR 4.40x10-5 4.74x10-5 4.92x10-5 2.08x10-5 2.13x10-5 3.13x10-5 8.48x10-5 9.55x10-5 4.89x10-6 1.84x10-5 6.07x10-5 6.07x10-5 3.63x10-5 4.74x10-5 3.71x10-5 3.70x10-5 5.10x10-5 7.38x10-5 4.33x10-6 3.40x10-5 7.02x10-5 7.37x10-7 1.00x10-4 1.68x10-3 1.68x10-3 1.68x10-3 1.40x10-3 1.40x10-3 1.63x10-3 2.02x10-3 2.07x10-3 6.53x10-4 1.40x10-3 1.83x10-3 1.83x10-3 1.63x10-3 1.68x10-3 1.63x10-3 1.63x10-3 1.69x10-3 1.93x10-3 6.53x10-4 1.63x10-3 1.93x10-3 4.04x10-4 2.07x10-3 2.56x10-6 5.61x10-4 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Calculation of Performance Measures for the ARPA-based predictive models Supplementary Table 4. (a) Possible results when the real and predicted early- and late-onset Alzheimer’s disease (AD) status are compared. Here, a is the number of individuals with early-onset AD (EO) that are correctly classified, b is the number of EO individuals classified as late-onset AD (LO), c corresponds to the number of LO cases classified as EO, and d to the number of LO cases correctly classified. (b) Expressions for calculating the performance measures used to quantitatively compare the CART, Random Forest and TreeNet strategies. (a) Prediction EOAD LOAD a b c d Phenotype EO (AOO < 48) LO (AOO ≥ 48) (b) Measure Sensitivity Specificity Precision Classification rate (CR) AOO: age of onset. Expression a / (a+c) d / (c+d) d / (c+d) (a+d) / (a+b+c+d) 0 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Gender-specific effects of genetic variants modifying ADAOO We performed a 2-based association analysis to assess gender-effects in the nine genetic variants reported to modify ADAOO in our 71 patients with PSEN1 E280A AD. Results of this analysis are presented below. Overall, no specific effects of these genetic variants by gender or education group were found. Supplementary Table 5. Gender-specific effects of genetic variants modifying ADAOO. SNP 2 Gene df P rs7412 APOE 0.014 1 0.906 rs36092215 GPR20 1.055 2 0.590 rs12364019 TRIM22 0.000 1 1.000 rs16838748 FCRL5 0.000 1 1.000 rs12701506 AOAH 1.019 2 0.601 rs2682585 PINLYP 2.002 2 0.367 rs62621173 IFI16 0.291 1 0.590 rs10798302 RC3H1 0.000 1 1.000 rs754554 DFNA5 1.530 2 0.465 2 = Test statistic; df = degrees of freedom; P = P-value. 1 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Number of variants per gene after filtering Number of genes (x 1000) 5 4 3 2 1 0 1 3 5 7 9 11 13 15 17 19 21 23 25 27 30 32 35 38 40 65 83 Number of variants per genes Supplementary Figure 4. Distribution of the number of common functional exonic variants (CEFVs) within genes. On average, ~2.83 CEFVs are located within each gene (standard deviation = 3.23). 2 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Power analysis Oligogenic model for detecting ADAOO modifiers Our power analysis using the pwr10 package in R11 suggests that, for a k=3 group design, 71 individuals would be sufficient to detect 80% true positives and a large effect (defined by the Cohen’s d parameter; d=0.82, Supplementary Figure 4) when m=100,000 variants are tested for association (a value that certainly overcomes the final number of variants used during the LMEM analyses). The selection of such effect is based on our hypothesis that variants of large effect (i.e., mutations) modify ADAOO in individuals with PSEN1 E280A AD (see also the 𝛽̂ coefficients in Table 1 of the manuscript); k is selected based on the maximum number of possible genotypes for a biallelic genetic marker; and m, as mentioned before, to be conservative. (b) 250 0.85 200 150 100 100 0.80 Power 0.75 0.70 50 150 0.85 1.0 0.9 0.80 0.8 0.75 0.7 0.70 0.6 Power 0.65 Cohen's d 0.5 0.600.4 0.65 50 n 2 0 250 (a) 0.4 0.6 0.8 1.0 Cohen's d Supplementary Figure 5. (a) Sample size (n) as a function of the Cohen’s effect size (d) and power. The type I error probability used for calculations is 0.05/100,000. In (b) the red dot corresponds to n=71, power = 80% and a large effect d = 0.82. It is also worth mentioning that d implies that d% of the ADAOO variance is explained by the m independent variables (i.e., ~100,000 genetic variants being tested). Our LMEMs estimates show that the percentage of ADAOO variance explained with only nine CEFVs (see Table 1 of the manuscript) tested for association is > 90% for the n=71 individuals. Under these conditions (d=0.9, n=71, m=40,000), the post hoc power estimate is of 96%, but for nine CEFVs the post hoc power estimate is of 99.9%. 3 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 Testing differences in ADAOO using extreme phenotypes from Genetic Isolate In addition, we have performed a power analysis to assess what the resulting sample size would be when a different split of the groups (in terms of the AOO) is used. As before, we utilized the pwr10 package in R11 to evaluate the power of a sample of n1 individuals with an ADAOO < 48 years and n2 individuals with ADAOO ≥ 48 years, using a two-sample t-test, for a wide range of effect sizes (f). Cohen (1988)12 suggests that values of f=0.2, 0.5, and 0.8 represent small, medium, and large effect sizes, respectively, where f is calculated as 𝜇1 −𝜇2 𝑓=| 𝜎 | (1) In our context, 𝜇1 and 𝜇2 are the population ADAOO for individuals with early- and late-onset AD, respectively, and 𝜎 2 is the common variance. We estimated 𝜇1 and 𝜇2 with the correspondent sample means (i.e., 44.2 and 53.5, respectively) and 𝜎 2 as 𝑆2 𝑆2 1 2 𝜎̂ 2 = 𝑛1 + 𝑛2 (2) In this formula, 𝑆12 and 𝑆22 are the sample estimates of the variance for the group of individuals with early- and late-ADAOO, respectively (i.e., 2.482 and 5.132 as reported in the second paragraph of the “E280A Pedigree” section). Thus, the sample effect size is f=8.936 (which corresponds to an extremely large effect size). The observed power of our study design is >99% when a type I error probability of 5% is used. Now, assuming a separation of eight years, no changes in the variance estimates and a sample size of n=71 individuals, the estimated effect size is f=7.687. The corresponding power would then be > 99%. In order to further study the power of our design under other conditions, we used a type I error probability of 5%, varied the sample sizes as n1 = n2 ={20, 40, 60, 80, 100} and f in the interval (0.1, 3) to cover small, medium, large and extremely large effect sizes (Cohen, 1988). The results are presented in Supplementary Figure 5 below. Overall, our study design has a power of >90% to detect effect sizes f > 0.8, which is a tenth of that actually observed. Hence, the ADAOO can be safely tested using our sample size, and our ad hoc separation of early and late onset. 4 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 100 a 1.0 0.7 80 0.8 0.6 n1 0.6 Power 60 0.4 0.5 0.2 0.4 40 0.0 100 100 80 80 0.3 60 60 n2 40 40 n1 20 20 20 20 40 60 80 100 80 100 80 100 n2 b 100 1.00 80 0.95 0.90 0.85 n1 Power 0.80 60 0.75 0.70 0.65 100 100 0.9 5 40 80 80 60 n1 0.8 0.8 5 0 60 40 40 n2 0.9 0 20 20 20 20 40 60 n2 c 100 1.00 80 0.99 0.98 n1 Power 0.97 60 0.96 0.95 100 100 40 80 80 n1 0.9 0.9 9 8 60 60 40 40 n2 20 20 20 20 40 60 n2 Supplementary Figure 6. Power analysis as a function of n1 and n2, the number of individuals with ADAOO<48 years and ADAOO ≥ 48 years, respectively, for a type I error probability of 5% and effect sizes (a) f = 0.4, (b) f = 0.8 and (c) f =1.2. The red dot corresponds to the power of our study design (n=71, n1=43, n2=28) for the effect size shown. 5 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 a 30 20 10 0 Squared error loss 40 School school APOE APOE IFI16 IFI16 DFAN5 DFNA5 RC3H1 RC3H1 Sexsex PINLYP PINLYP GPR20 GPR20 TRIM22 TRIM22 FCRL5 FCRL5 AOAH AOAH 0 b Iteration 40 30 20 Squared error loss 10 1000 2000 3000 4000 5000 Iteration 0 40 30 20 10 1000 2000 3000 4000 5000 Iteration 20 30 40 50 10 20 30 40 Relative influence school School APOE APOE IFI16 IFI16 DFNA5 DFAN5 Sexsex RC3H1 RC3H1 PINLYP PINLYP GPR20 GPR20 AOAH AOAH TRIM22 TRIM22 FCRL5 FCRL5 0 Squared error loss 0 10 Relative influence School school APOE APOE IFI16 IFI16 DFAN5 DFNA5 Sexsex RC3H1 RC3H1 PINLYP PINLYP GPR20 GPR20 AOAH AOAH TRIM22 TRIM22 FCRL5 FCRL5 0 0 c 0 1000 2000 3000 4000 5000 0 10 20 30 40 Relative influence Supplementary Figure 7. Squared error loss (left) and relative importance (right) for the best fitting generalized boosting regression model (GBRM) when the (a) out-of-bag, (b) test data set and (c) crossvalidation error are used, and the ADAOO is introduced as a continuous variable. Based on the minimum mean squared error, a measure of model fitting, model (b) was selected. The black, red, green and blue lines in the left panel correspond to the training data set, the test data set, the crossvalidation, and the best performing model, respectively. Note that the variable importance plots on the right are similar to those obtained when the ADAOO was introduced as a binary variable. 6 Mutations Modifying the Age of Onset of Dementia Vélez et al. 2015 REFERENCES 1. Petersen RC, Smith GE, Waring SC, Ivnik RJ, Tangalos EG, Kokmen E. Mild cognitive impairment: clinical characterization and outcome. Arch Neurol 1999; 56(3): 303-308. 2. 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