APOE ε4 carrier status modifies plasma p-tau181 concentrations in cognitively healthy super-seniors.

INTRODUCTION: This study investigates the effect of apolipoprotein E (APOE) genotype on neurology plasma biomarkers in cognitively healthy Super-Seniors. METHODS: Three hundred seventy plasma specimens from Super-Senior participants ≥ 85 years old, who have never been diagnosed with dementia, cancer, diabetes, cardiovascular, or major pulmonary disease, were analyzed on the Quanterix Simoa HD-X analyzer using commercial Neurology 4-plex E and phosphorylated tau (p-tau)181 assays. RESULTS: Eighty (22%) participants were APOE ε4 carriers and 290 (73%) were non-carriers. No significant differences were found between APOE ε4 carriers and non-carriers regarding age, sex, or Mini-Mental State Examination scores. In APOE ε4 carriers, plasma amyloid beta 42/40 was lower and p-tau181 and glial fibrillary acidic protein were higher compared to non-APOE ε4 carriers. After adjusting for demographic variables, p-tau181 was the only biomarker to remain significantly associated with APOE ε4 carrier status. DISCUSSION: APOE ε4 genotype modifies plasma p-tau181 concentration in seniors resilient to age-related clinical disease, suggesting that some Super-Seniors may have Alzheimer's disease pathology without progressing to cognitive decline. HIGHLIGHTS: Healthy seniors enable identification of associations that may be masked by disease. Plasma phosphorylated tau (p-tau)181 concentrations associate with apolipoprotein E (APOE) ε4 carriership in healthy seniors. APOE should be accounted for when interpreting p-tau181, regardless of disease.

Costs and Effects of School-Based Licensed Practical Nurses on Elementary Student Attendance and Chronic Absenteeism.

Despite increasing reliance on licensed practical nurses (LPNs) to provide health services in schools, we do not know whether this is a cost-effective prevention strategy against student absenteeism. Therefore, we evaluated the costs and effectiveness of an LPN-based school nursing program for improving attendance and chronic absenteeism at a large, urban school district in the southeastern USA. We first identified a matched set of 46 elementary schools (23 nurse, 23 no-nurse) by using an optimal multilevel matching algorithm based on student- and school-level characteristics. We then conducted a cost-effectiveness analysis on the matched set, using the ingredients method to estimate societal costs and multilevel regression to estimate effects. The results indicated that despite substantial incremental costs of $68,228 per school, the presence of a full-time LPN was associated with at best negligible improvements, and at worst slight disimprovements, in attendance and chronic absenteeism. We recommend a careful review of the theory of change for LPN-based school nursing programs to clarify the specific inputs and activities that are expected to lead to improved student outcomes. Education agencies should develop explicit assignment, training, monitoring, and auditing plans to ensure LPNs are equitably distributed and that their activities are aligned with the theory of change. Education agencies should also explore whether expanded Medicaid billing can reduce their share of the nursing cost burden.

Families and Schools Together (FAST) for improving outcomes for children and their families.

BACKGROUND: Parents and carers have a major influence on children's learning and development from birth, through the school years, and into adulthood. Parental contributions to education include providing a secure environment in which to learn, providing intellectual stimulation, transmitting social norms and values, shaping the child's resilience through fostering literacy and problem-solving, and encouraging personal and social aspiration. Increasingly, providers of formalised education are recognising the primary role of parents, carers, and the wider family, as well as peers and the environment, in shaping children's education, health, and life experiences. OBJECTIVES: To assess the effectiveness of the Families and Schools Together (FAST) programme in improving outcomes among children and their families. SEARCH METHODS: Between October 2018 and December 2018, we searched CENTRAL, MEDLINE, Embase, PsycINFO, 11 additional databases, and three trial registers. We handsearched the reference lists of included studies and relevant reports and reviews, contacted the programme developer and independent researchers, and searched relevant websites to identify other eligible studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs examining the effects of FAST, relative to waiting list, usual or alternative services, or no intervention, on outcomes for children (aged from birth to completion of compulsory education) and their families. DATA COLLECTION AND ANALYSIS: At least two review authors independently evaluated the records retrieved from the search for relevance. One review author (JV) extracted data from eligible studies with a second independent review author (AF, DK, or SL). Review authors consulted with one another to resolve disagreements. We used a fixed-effect model for meta-analysis. We presented results as standardised mean differences (SMDs) because all outcomes were continuously scaled, and we accompanied these with 95% confidence intervals (CIs). We used the GRADE approach to assess the certainty of evidence for each outcome. MAIN RESULTS: We identified 10 completed RCTs, most of which were relatively recent (2007 or later) and were conducted with at least some involvement from the intervention developer or the FAST organisation. Nine of the 10 trials were from the USA; the other was from the UK. Children were young (five to nine years old; mean age approximately six years), and therefore, whilst not so named in the reports, evaluations consisted of what is sometimes referred to as 'Kids FAST' and sometimes 'Elementary Level FAST'). Among the USA-based studies, at least 62% of participants were members of a racial/ethnic minority group (most commonly, African American or Latino). FAST was usually delivered in schools after the school day. Trials lasted about eight weeks and usually examined the effects of FAST relative to no additional intervention. Most studies were funded by agencies in the US federal government. We judged the certainty of evidence in the included studies to be moderate or low for the main review outcomes. Failure to include all families in outcome analyses (attrition) and possible bias in recruitment of families into the trials were the main limitations in the evidence.We included over 9000 children and their families in at least one meta-analysis. The follow results relate to meta-analyses of data at long-term follow-up.Primary outcomesFour studies (approximately 6276 children) assessed child school performance at long-term follow-up. The effect size was very small, and the CI did not include effects that, if real, suggest possibly important positive or negative effects if viewed from an individual perspective (SMD -0.02, 95% CI -0.11 to 0.08). We assessed the certainty of evidence for this outcome as moderate. No studies assessed child adverse events, parental substance use, or parental stress.Secondary outcomesParent reports of child internalising behaviour (SMD -0.03, 95% CI -0.11 to 0.17; 4 RCTs, approximately 908 children; low-certainty evidence) and family relationships (SMD 0.08, 95% CI -0.03 to 0.19; 4 RCTs, approximately 2569 children; moderate-certainty evidence) also yielded CIs that did not include effects that, if real, suggest possibly important positive or negative effects.The CI for parent reports of child externalising behaviour, however, did include effects that, if real, were possibly large enough to be important (SMD -0.19, 95% CI -0.32 to -0.05; 4 RCTs, approximately 754 children; low-certainty evidence). AUTHORS' CONCLUSIONS: Given these results, it is hard to support the assertion that assignment to FAST is associated with important positive outcomes for children and their parents.

Structure and Reactivity of Al-O(H)-Al Moieties in Siloxide Frameworks: Solution and Gas-Phase Model Studies.

Even though aluminas and aluminosilicates have found widespread application, a consistent molecular understanding of their surface heterogeneity and the behavior of defects resulting from hydroxylation/dehydroxylation remains unclear. Here, we study the well-defined molecular model compound, [Al3 (µ2 -OH)3 (THF)3 (PhSi(OSiPh2 O)3 )2 ], 1, to gain insight into the acid-base reactivity of cyclic trinuclear Al3 (µ2 -OH)3 moieties at the atomic level. We find that, like zeolites, they are sufficiently acidic to catalyze the isomerization of olefins. DFT and gas phase vibrational spectroscopy on solvent-free and deprotonated 1 show that the six-membered ring structure of its Al3 (µ2 -OH)3 core is unstable with respect to deprotonation of one of its hydroxy groups and rearranges into two edge-sharing four-membered rings. This renders AlIV -O(H)-AlIV units strong acid sites, and all results together suggest that their acidity is similar to that of zeolitic SiIV -O(H)-AlIV groups.

Precipitating polyelectrolyte-surfactant systems by admixing a nonionic surfactant - a case of cononsurfactancy.

The formation of water insoluble polyelectrolyte/surfactant complexes (PESCs) upon mixing two homogeneous polycation/anionic surfactant and polycation/nonionic surfactant solutions is reported here. This phase separation is unexpected and differs markedly from the commonly observed enhanced solubility of colloidal systems in mixed surfactant systems. The study was performed on mixtures of the cationic biopolysaccharide chitosan (poly d-glucosamine) and mixed micelles composed of an ethoxylated fatty alcohol and its carboxylic acid terminated equivalent. The thermodynamics of mixing was probed via isothermal titration calorimetry (ITC), while the structural characterisation was conducted by means of light and neutron scattering (SANS). The results show that the substitution of a weakly anionic surfactant with its nonionic equivalent has profound effects on the interactions at very different length scales. The dilution of the ionic headgroups allows for a more efficient interaction between micelles and polymer chains, and results in an elongation of the mixed micelles which reduces the bending cost of the semi-rigid chitosan and introduces an additional attractive potential of entropic origin. In this work, as a result of a comprehensive thermodynamic and structural analysis, we demonstrate how the subtle interplay of different forces leads to such an unexpected behaviour, where the addition of a nonionic surfactant causes the phase separation of electrostatic complexes.

Burden of Common Complex Disease Variants in the Exomes of Two Healthy Centenarian Brothers.

BACKGROUND: It is not understood whether long-term good health is promoted by the absence of disease risk variants, the presence of protective variants, or both. We characterized the exomes of two exceptionally healthy centenarian brothers aged 106 and 109 years who had never been diagnosed with cancer, cardiovascular disease, diabetes, Alzheimer's disease, or major pulmonary disease. OBJECTIVE: The aim of this study was to gain insight into whether exceptional health and longevity are a result of carrying fewer disease-associated variants than typical individuals. METHODS: We compared the number of disease-associated alleles, and the proportion of alleles predicted to be functionally damaging, between the centenarian brothers and published population data. Mitochondrial sequence reads were extracted from the exome data in order to analyze mitochondrial variants. RESULTS: The brothers carry a similar number of common disease-associated variants and predicted damaging variants compared to reference groups. They did not carry any high-penetrance clinically actionable variants. They carry mitochondrial haplogroup T, and one brother has a single heteroplasmic variant. CONCLUSION: Although our small sample size does not allow for definitive conclusions, a healthy aging and longevity phenotype is not necessarily due to a decreased burden of common disease-associated variants. Instead, it may be rare 'positive' variants that play a role in this desirable phenotype.

GWAS of follicular lymphoma reveals allelic heterogeneity at 6p21.32 and suggests shared genetic susceptibility with diffuse large B-cell lymphoma.

Non-Hodgkin lymphoma (NHL) represents a diverse group of hematological malignancies, of which follicular lymphoma (FL) is a prevalent subtype. A previous genome-wide association study has established a marker, rs10484561 in the human leukocyte antigen (HLA) class II region on 6p21.32 associated with increased FL risk. Here, in a three-stage genome-wide association study, starting with a genome-wide scan of 379 FL cases and 791 controls followed by validation in 1,049 cases and 5,790 controls, we identified a second independent FL-associated locus on 6p21.32, rs2647012 (OR(combined)  = 0.64, P(combined)  = 2 × 10(-21)) located 962 bp away from rs10484561 (r(2)<0.1 in controls). After mutual adjustment, the associations at the two SNPs remained genome-wide significant (rs2647012:OR(adjusted)  = 0.70, P(adjusted)  =  4 × 10(-12); rs10484561:OR(adjusted)  = 1.64, P(adjusted)  = 5 × 10(-15)). Haplotype and coalescence analyses indicated that rs2647012 arose on an evolutionarily distinct haplotype from that of rs10484561 and tags a novel allele with an opposite (protective) effect on FL risk. Moreover, in a follow-up analysis of the top 6 FL-associated SNPs in 4,449 cases of other NHL subtypes, rs10484561 was associated with risk of diffuse large B-cell lymphoma (OR(combined)  = 1.36, P(combined)  =  1.4 × 10(-7)). Our results reveal the presence of allelic heterogeneity within the HLA class II region influencing FL susceptibility and indicate a possible shared genetic etiology with diffuse large B-cell lymphoma. These findings suggest that the HLA class II region plays a complex yet important role in NHL.

Material circumstances, health care access, and self-reported health: A latent class analysis.

Latent class analysis was used to explore intersections of material circumstances and health care access among 308 adults, and associations between classes with health outcomes. Good fit was found for a four-class model: Resource Stable (Class 1, 62.43%), Unbalanced Meals with Health Care (Class 2, 16.91%), Resource Insecurity with Delayed Health Care (Class 3, 14.75%), and Resource Stability without Access to Health Care (Class 4, 5.91%). Class 1 reported greater well-being and self-rated health than Class 2 and 3. Class 1 reported lower BMI than Class 2. Findings document intersections among economic marginalization indicators with varying health outcomes among classes.

Gene and pathway based burden analyses in familial lymphoid cancer cases: Rare variants in immune pathway genes.

Genome-wide association studies have revealed common genetic variants with small effect sizes associated with diverse lymphoid cancers. Family studies have uncovered rare variants with high effect sizes. However, these variants explain only a portion of the heritability of these cancers. Some of the missing heritability may be attributable to rare variants with small effect sizes. We aim to identify rare germline variants associated with familial lymphoid cancers using exome sequencing. One case per family was selected from 39 lymphoid cancer families based on early onset of disease or rarity of subtype. Control data was from Non-Finnish Europeans in gnomAD exomes (N = 56,885) or ExAC (N = 33,370). Gene and pathway-based burden tests for rare variants were performed using TRAPD. Five putatively pathogenic germline variants were found in four genes: INTU, PEX7, EHHADH, and ASXL1. Pathway-based association tests identified the innate and adaptive immune systems, peroxisomal pathway and olfactory receptor pathway as associated with lymphoid cancers in familial cases. Our results suggest that rare inherited defects in the genes involved in immune system and peroxisomal pathway may predispose individuals to lymphoid cancers.

Restorative Practices: Using local evidence on costs and student outcomes to inform school district decisions about behavioral interventions.

School disciplinary practices affect student academic and life outcomes. Many schools have recently shifted towards the prevention of behavioral disorders rather than the punishment of such disorders, but disciplinary actions are still disproportionately meted out to Black students. We took advantage of a natural experiment in a large school district to investigate the costs and effects of a school-wide intervention based on the principles of restorative justice on suspensions, referrals, and three school climate constructs. The study involved 14 elementary and middle schools, each of which was already implementing Positive Behavioral Interventions and Supports (PBIS). Six of the schools integrated Restorative Practices into their PBIS framework during the first year of the study, whereas the other eight served as comparison schools and implemented the program the following year. We tested a difference-in-difference regression model for each of our five outcomes of interest after 1 year of implementation using Quasi-Poisson models for referrals and suspensions. We found no statistically significant effects on four of the outcomes, either for the overall sample or by racial subgroup. We found negative effects on student-reported personal safety. An additional analysis 1 year later showed that Black students in schools implementing Restorative Practices for 2 years experienced a greater reduction in suspensions than Black students in schools implementing the program for only 1 year. We used the ingredients method to estimate start-up costs and ongoing costs for the first full year of implementation. Our reference case analysis results using a societal perspective, national average prices, and a 3% discount rate were $57,450 per school and $139 per student for the first year of Restorative Practices implementation. These estimates included training costs from the prior year and were incremental to the costs of PBIS, which served as the business-as-usual condition. We compared these costs to those of a number of other behavioral interventions and concluded that Restorative Practices are relatively low cost but may need to be implemented for several years with greater fidelity in order to produce the desired improvements in behavior events and school climate.

Diffuse large B-cell lymphoma: reduced CD20 expression is associated with an inferior survival.

CD19 and CD20 are B cell-specific antigens whose expression is heterogeneous when analyzed by flow cytometry (FCM). We determined the association between CD20 expression and clinical outcome in patients with diffuse large B-cell lymphoma (DLBCL). The mean fluorescence intensity of CD20 and CD19 was determined by FCM, and the cytoplasmic expression of CD20 was determined by immunohistochemistry (IHC) on 272 diagnostic DLBCL samples. Exon 5 of the MS4A1 gene coding for the extracellular component of the CD20 antigen was sequenced in 15 samples. A total of 43 of 272 (16%) samples had reduced CD20 expression by FCM; of these, 35 (13%) had bright CD19 expression. The latter had a markedly inferior survival when treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or rituximab-CHOP (R-CHOP; median survival of 1.2 and 3.0 years vs not reached for the others, P < .001 and P = .001), independent of the International Prognostic Index. A total of 41 of 43 samples with reduced CD20 expression by FCM had strong staining for CD20 by IHC. There were no mutations in exon 5 of the MS4A1 gene to explain the discrepancy between FCM and IHC. CD20 and CD19 expression by FCM should be determined on all biopsies of patients with DLBCL because reduced CD20 expression cannot be reliably detected by IHC.

Mindfulness, self-reported health, and cortisol: A latent profile analysis.

This study utilized a latent profile analysis approach to examine the relationship between mindfulness profiles and self-reported mental and physical health, as well as salivary cortisol levels in a sample of 85 undergraduate students. Consistent with theory, the Judgmentally Observing (high monitoring, low acceptance) reported poorer mental health and exhibited flatter diurnal cortisol slopes than the Unobservant Accepting (low monitoring, high acceptance) and Average Mindfulness profiles. No differences in self-reported physical health, cortisol response to awakening, or diurnal mean cortisol were observed among the profiles. Future directions are discussed.

Interaction between organochlorines and the AHR gene, and risk of non-Hodgkin lymphoma.

BACKGROUND: Plasma organochlorines have been implicated to increase the risk of non-Hodgkin lymphoma (NHL), and interaction with the aryl hydrocarbon receptor gene (AHR) may modify this risk. METHODS: In this case-control study conducted in British Columbia, Canada, five single nucleotide polymorphisms (SNPs) of AHR were genotyped in 422 NHL cases and 459 controls to measure the association between individual SNPs, haplotypes, and risk of NHL. Pre-chemotherapy organochlorine levels were measured and gene-environment interaction analysis was performed. RESULTS: The IVS1 + 4640G/A SNP was significantly associated with NHL risk, with an odds ratio of 1.32 (95% CI = 1.05-1.65) for G/A or A/A genotypes compared to the G/G genotype. Interactions were observed with PCB 118, a known inducer of AHR, and chlordane-related analytes oxychlordane and trans-nonachlor, although no interactions were statistically significant after controlling for multiple comparisons. The observed interactions were consistent across NHL subtypes. CONCLUSION: Results suggest that the AHR gene may play a role in determining the risk of NHL with exposure to organochlorines, and highlight the importance of understanding gene-environment interactions.

Allele-Specific Transcript Abundance: A Pilot Study in Healthy Centenarians.

The genetic basis of healthy aging and longevity remains largely unexplained. One hypothesis as to why long-lived individuals do not appear to have a lower number of common-complex disease variants, is that despite carrying risk variants, they express disease-linked alleles at a lower level than the wild-type alleles. Allele-specific abundance (ASA) is the different transcript abundance of the two haplotypes of a diploid individual. We sequenced the transcriptomes of four healthy centenarians and four mid-life controls. CIBERSORT was used to estimate blood cell fractions: neutrophils were the most abundant source of RNA, followed by CD8+ T cells, resting NK cells, and monocytes. ASA variants were more common in noncoding than coding regions. Centenarians and controls had a comparable distribution of ASA variants by predicted effect, and we did not observe an overall bias in expression toward major or minor alleles. Immune pathways were most highly represented among the gene set that showed ASA. Although we found evidence of ASA in disease-associated genes and transcription factors, we did not observe any differences in the pattern of expression between centenarians and controls in this small pilot study.

Genetic variation in the NBS1, MRE11, RAD50 and BLM genes and susceptibility to non-Hodgkin lymphoma.

BACKGROUND: Translocations are hallmarks of non-Hodgkin lymphoma (NHL) genomes. Because lymphoid cell development processes require the creation and repair of double stranded breaks, it is not surprising that disruption of this type of DNA repair can cause cancer. The members of the MRE11-RAD50-NBS1 (MRN) complex and BLM have central roles in maintenance of DNA integrity. Severe mutations in any of these genes cause genetic disorders, some of which are characterized by increased risk of lymphoma. METHODS: We surveyed the genetic variation in these genes in constitutional DNA of NHL patients by means of gene re-sequencing, then conducted genetic association tests for susceptibility to NHL in a population-based collection of 797 NHL cases and 793 controls. RESULTS: 114 SNPs were discovered in our sequenced samples, 61% of which were novel and not previously reported in dbSNP. Although four variants, two in RAD50 and two in NBS1, showed association results suggestive of an effect on NHL, they were not significant after correction for multiple tests. CONCLUSION: These results suggest an influence of RAD50 and NBS1 on susceptibility to diffuse large B-cell lymphoma and marginal zone lymphoma. Larger association and functional studies could confirm such a role.

CD20 mutations involving the rituximab epitope are rare in diffuse large B-cell lymphomas and are not a significant cause of R-CHOP failure.

Rituximab binds an epitope on the CD20 antigen, encompassed in exon 5 of the MS4A1 gene. We sequenced this region and correlated the presence of mutations with CD20 protein expression and response to R-CHOP in patients with diffuse large B-cell lymphoma: 264 diagnostic biopsies and 15 biopsies taken at the time of relapse were successfully sequenced. CD20 mutations involving the rituximab epitope were detected in only 1/264 (0.4%) and 1/15 (6%) of the biopsies taken at diagnosis and relapse, respectively. No polymorphic sequence variants were detected in this region. Three patients had malignant cells that were CD20 protein-positive at diagnosis but CD20-negative at relapse. Thus, CD20 mutations involving the rituximab epitope are rare in both de novo and relapsed diffuse large B-cell lymphoma, and do not represent a significant cause of R-CHOP resistance. CD20 protein-negative relapses occur after R-CHOP therapy but their clinical relevance is unknown.

Initial association of NR2E1 with bipolar disorder and identification of candidate mutations in bipolar disorder, schizophrenia, and aggression through resequencing.

Nuclear receptor 2E1 gene (NR2E1) resides within a 6q21-22 locus for bipolar disorder and schizophrenia. Mice deleted for Nr2e1 show altered neurogenesis, cortical and limbic abnormalities, aggression, hyperexcitability, and cognitive impairment. NR2E1 is therefore a positional and functional candidate for involvement in mental illness. We performed association analyses in 394 patients with bipolar disorder, 396 with schizophrenia, and 479 controls using six common markers and haplotypes. We also performed a comprehensive mutation screen of NR2E1, resequencing its entire coding region, complete 5' and 3' untranslated regions, consensus splice-sites, and evolutionarily conserved regions in 126 humans with bipolar disorder, schizophrenia, or aggressive disorders. NR2E1 was associated with bipolar disorder I and II [odds ratio (OR = 0.77, P = 0.013), bipolar disorder I (OR = 0.77, P = 0.015), bipolar disorder in females (OR = 0.72, P = 0.009), and with age at onset < or = 25 years (OR = 0.67, P = 0.006)], all of which remained significant after correcting for multiple comparisons. We identified eight novel candidate mutations that were absent in 325 controls; four of these were predicted to alter known neural transcription factor binding sites. Analyses of NR2E1 mRNA in human brain revealed forebrain-specific transcription. The data presented support the hypothesis that genetic variation at NR2E1 may be associated with susceptibility to brain-behavior disorders.

The Super-Seniors Study: Phenotypic characterization of a healthy 85+ population.

BACKGROUND: To understand why some people live to advanced age in good health and others do not, it is important to study not only disease, but also long-term good health. The Super-Seniors Study aims to identify factors associated with healthy aging. METHODS: 480 healthy oldest-old 'Super-Seniors' aged 85 to 105 years and never diagnosed with cancer, cardiovascular disease, diabetes, dementia, or major pulmonary disease, were compared to 545 mid-life controls aged 41-54, who represent a group that is unselected for survival from late-life diseases. Health and lifestyle information, personal and family medical history, and blood samples were collected from all participants. Super-Seniors also underwent four geriatric tests. RESULTS: Super-Seniors showed high cognitive (Mini-Mental State Exam mean = 28.3) and functional capacity (Instrumental Activities of Daily Living Scale mean = 21.4), as well as high physical function (Timed Up and Go mean = 12.3 seconds) and low levels of depression (Geriatric Depression Scale mean = 1.5). Super-Seniors were less likely to be current smokers than controls, but the frequency of drinking alcohol was the same in both groups. Super-Seniors were more likely to have 4 or more offspring; controls were more likely to have no children. Female Super-Seniors had a mean age of last fertility 1.9 years older than controls, and were 2.3 times more likely to have had a child at ≥ 40 years. The parents of Super-Seniors had mean ages of deaths of 79.3 years for mothers, and 74.5 years for fathers, each exceeding the life expectancy for their era by a decade. CONCLUSIONS: Super-Seniors are cognitively and physically high functioning individuals who have evaded major age-related chronic diseases into old age, representing the approximately top 1% for healthspan. The familiality of long lifespan of the parents of Super-Seniors supports the hypothesis that heritable factors contribute to this desirable phenotype.

Genetic variation in H2AFX contributes to risk of non-Hodgkin lymphoma.

Non-Hodgkin lymphoma (NHL) comprises a group of lymphoid tumors that have in common somatic translocations. H2AFX encodes a key histone involved in the detection of the DNA double-stranded breaks that can lead to translocations. H2afx is a dosage-dependent gene that protects against B-cell lymphomas in mice, making its human orthologue an ideal candidate gene for susceptibility to lymphoma. We did a population-based genetic association study of H2AFX variants in 487 NHL cases and 531 controls. Complete resequencing of the human H2AFX gene in 95 NHL cases was done to establish the spectrum of variation in affected individuals; this was followed by both direct and indirect tests for association at the level of individual single nucleotide polymorphisms (SNP) and as haplotypes. Homozygosity for the AA genotype of a SNP 417 bp upstream of the translational start of H2AFX is strongly associated [odds ratio (OR), 0.54; P = 0.001] with protection from NHL. We find a strong association of this SNP with the follicular lymphoma subtype of NHL (AA genotype: OR, 0.40; P = 0.004) and with mantle cell lymphoma (AA genotype: OR, 0.20; P = 0.01) that remains significant after adjustment for the false discovery rate, but not with diffuse large B-cell lymphoma. These data support the hypothesis that genetic variation in the H2AFX gene influences genetic susceptibility or resistance to some subtypes of NHL by contributing to the maintenance of genome stability.