Disparities in ambient nitrogen dioxide pollution in the United States.

Average ambient concentrations of nitrogen dioxide (NO2), an important air pollutant, have declined in the United States since the enactment of the Clean Air Act. Despite evidence that NO2 disproportionately affects racial/ethnic minority groups, it remains unclear what drives the exposure disparities and how they have changed over time. Here, we provide evidence by integrating high-resolution (1 km × 1 km) ground-level NO2 estimates, sociodemographic information, and source-specific emission intensity and location for 217,740 block groups across the contiguous United States from 2000 to 2016. We show that racial/ethnic minorities are disproportionately exposed to higher levels of NO2 pollution compared with Whites across the United States and within major metropolitan areas. These inequities persisted over time and have worsened in many cases, despite a significant decrease in the national average NO2 concentration over the 17-y study period. Overall, traffic contributes the largest fraction of NO2 disparity. Contributions of other emission sources to exposure disparities vary by location. Our analyses offer insights into policies aimed at reducing air pollution exposure disparities among races/ethnicities and locations.

Childhood Racism and Cardiometabolic Risk in Latina Mothers Across the First Postpartum Year.

OBJECTIVE: Immigrant Latinas, particularly of Mexican descent, initially achieve healthy perinatal outcomes. Although this advantage wears off across generations in the United States (US), the early life psychosocial mechanisms that may initiate a cascade of biological vulnerabilities remain elusive. The current investigation aimed to understand the extent to which childhood experiences of racism may contribute to elevated levels of C-reactive protein (CRP), an early indicator of cardiometabolic risk, during the first postpartum year. METHODS: Latinas from the Community and Child Health Network ( N = 457) retrospectively reported experiences of childhood racism and childhood country of residence via structured questionnaires. Interviewers collected CRP bloodspots and height and weight measurements for body mass index at 6 months and 1 year postpartum. RESULTS: Latinas who grew up in the US experienced a steeper increase of CRP levels across the first postpartum year ( ß = 0.131, p = .009) and had higher CRP levels 1 year postpartum than Latinas who grew up in Latin America. Based on Bayesian path analyses, Latinas who grew up in the US reported higher levels of childhood racism than Latinas who immigrated after childhood ( ß = 0.27; 95% credible interval = 0.16-0.37). In turn, childhood racism mediated the relationship between country of childhood residence and elevated CRP at 6 months and 1 year postpartum, even after adjusting for sociodemographic and behavioral covariates. After adjusting for body mass index, mediational relationships became nonsignificant. CONCLUSIONS: This study is an important first step toward understanding how childhood racism may contribute to postmigratory health patterns among Latinas, particularly cardiometabolic risk 1 year after childbirth.

Intergenerational Transmission of Ethnoracial Historical Trauma in the United States.

Throughout time, ethnoracial groups have endured a range of traumatic experiences as historically marginalized members of the United States. The consequences of these experiences have been referred to as historical trauma (HT): a collective trauma, inflicted on a group of people who share a specific identity, that has psychological, physical, and social impacts on succeeding generations. In this review, we examine the literature on HT in relation to US ethnoracial groups by defining HT, providing a background for its development, and describing critiques of the concept. We then review the literature on HT in relation to Indigenous Americans, African Americans, and Asian Americans. For each group, we address the nature of HT, the transmission of HT and its impacts, and healing strategies. We conclude with a summary of the benefits, limitations, and complexities of HT research as well as recommendations for future work in this area.

Persuading US White evangelicals to vaccinate for COVID-19: Testing message effectiveness in fall 2020 and spring 2021.

The development of COVID-19 vaccines was an important breakthrough for ending the pandemic. However, people refusing to get vaccinated diminish the level of community protection afforded to others. In the United States, White evangelicals have proven to be a particularly difficult group to convince to get vaccinated. Here we investigate whether this group can be persuaded to get vaccinated. To do this, we leverage data from two survey experiments, one fielded prior to approval of COVID-19 vaccines (study 1) and one fielded after approval (study 2). In both experiments, respondents were randomly assigned to treatment messages to promote COVID-19 vaccination. In study 1, we find that a message that emphasizes community interest and reciprocity with an invocation of embarrassment for choosing not to vaccinate is the most effective at increasing uptake intentions, while values-consistent messaging appears to be ineffective. In contrast, in study 2 we observe that this message is no longer effective and that most messages produce little change in vaccine intent. This inconsistency may be explained by the characteristics of White evangelicals who remain unvaccinated vis à vis those who got vaccinated. These results demonstrate the importance of retesting messages over time, the apparent limitations of values-targeted messaging, and document the need to consider heterogeneity even within well-defined populations. This work also cautions against drawing broad conclusions from studies carried out at a single point in time during the COVID-19 pandemic.

Pandemic precarity: COVID-19 is exposing and exacerbating inequalities in the American heartland.

Crises lay bare the social fault lines of society. In the United States, race, gender, age, and education have affected vulnerability to COVID-19 infection. Yet, consequences likely extend far beyond morbidity and mortality. Temporarily closing the economy sent shock waves through communities, raising the possibility that social inequities, preexisting and current, have weakened economic resiliency and reinforced disadvantage, especially among groups most devastated by the Great Recession. We address pandemic precarity, or risk for material and financial insecurity, in Indiana, where manufacturing loss is high, metro areas ranked among the hardest hit by the Great Recession nationally, and health indicators stand in the bottom quintile. Using longitudinal data (n = 994) from the Person to Person Health Interview Study, fielded in 2019-2020 and again during Indiana's initial stay-at-home order, we provide a representative, probability-based assessment of adverse economic outcomes of the pandemic. Survey-weighted multivariate regressions, controlling for preexisting inequality, find Black adults over 3 times as likely as Whites to report food insecurity, being laid off, or being unemployed. Residents without a college degree are twice as likely to report food insecurity (compared to some college), while those not completing high school (compared to bachelor's degree) are 4 times as likely to do so. Younger adults and women were also more likely to report economic hardships. Together, the results support contentions of a Matthew Effect, where pandemic precarity disproportionately affects historically disadvantaged groups, widening inequality. Strategically deployed relief efforts and longer-term policy reforms are needed to challenge the perennial and unequal impact of disasters.

Associations of Household and Neighborhood Contexts and Hair Cortisol Among Mexican-Origin Adolescents From Low-Income Immigrant Families.

Although neighborhood contexts serve as upstream determinants of health, it remains unclear how these contexts "get under the skin" of Mexican-origin youth, who are disproportionately concentrated in highly disadvantaged yet co-ethnic neighborhoods. The current study examines the associations between household and neighborhood socioeconomic status (SES), neighborhood racial-ethnic and immigrant composition, and hair cortisol concentration (HCC)-a physiological index of chronic stress response-among Mexican-origin adolescents from low-income immigrant families in the United States. A total of 297 (54.20% female; mage = 17.61, SD = 0.93) Mexican-origin adolescents had their hair cortisol collected, and their residential addresses were geocoded and merged with the American Community Survey. Neighborhoods with higher Hispanic-origin and foreign-born residents were associated with higher neighborhood disadvantage, whereas neighborhoods with higher non-Hispanic White and domestic-born residents were associated with higher neighborhood affluence. Mexican-origin adolescents living in neighborhoods with a higher proportion of Hispanic-origin residents showed lower levels of HCC, consistent with the role of the ethnic enclave. In contrast, adolescents living in more affluent neighborhoods showed higher levels of HCC, possibly reflecting a physiological toll. No association was found between household SES and HCC. Our findings underscore the importance of taking sociocultural contexts and person-environment fit into consideration when understanding how neighborhoods influence adolescents' stress physiology.

Associations between gendered racism, racial identity, and nicotine use among Asian American men.

OBJECTIVES: The present study utilized an intersectional framework to examine if two forms of gendered racism, psychological emasculation and messages about Asian American men being undesirable partners, were associated with Asian American men's nicotine use. We also examined the potential mediating roles of two racial identity statuses, racial conformity and racial immersion. METHODS: A sample of 356 Asian American men living in the United States of America (USA) completed a cross-sectional survey via Qualtrics containing measures assessing the aforementioned constructs of interest. The primary analysis examined separate parallel mediation models, situating psychological emasculation and undesirable partner as separate independent variables, racial conformity and racial immersion as parallel mediators, nicotine use as the outcome, and age and employment as covariates. RESULTS: In separate parallel mediation models, the links between psychological emasculation and undesirable partner on one hand, and nicotine use on the other, were completely mediated only by racial conformity, and not significantly mediated by racial immersion. Specifically, greater endorsement of gendered racism was associated with greater conformity with (and internalization of) these gendered racist beliefs, which in turn were associated with greater nicotine use. CONCLUSION: Researchers and practitioners may consider racial conformity as an interventional target to ameliorate Asian American men's nicotine use. Future studies should continue to examine other culturally relevant and/or potentially protective constructs (e.g., on the basis of gender, race, and its intersection) that may mitigate Asian American men's nicotine use.

The Effect of Financial Strain on the Health Outcomes of Older Mexican-Origin Adults: Findings From the Hispanic Established Population for the Epidemiological Study of the Elderly (H-EPESE).

Predictors of health across the life-course do not maintain the same significance in very late life and the role of financial strain in health outcomes of very old adults remain unclear. Data from adults aged 74 + in waves 5 and 7 of the Hispanic Established Population for the Epidemiological Study of the Elderly (n = 772) study was used to evaluate the role of financial strain on the health of older Mexican Americans who have the highest poverty rate of any racial or ethnic group in the United States. We evaluate the association between episodic (one wave) and persistent financial strain (two waves), with follow-up health outcomes (self-rated health, ADL (limitations in activities of daily living)/IADL (limitations in instrumental activities of daily living) disability, and depressive symptoms). Adults with persistent strain were twice as likely to experience depressive symptoms and three times more likely to experience IADL limitations than the unstrained. Our findings highlight the role of stress proliferation and allostatic load processes leading to deteriorated health over time.

Cultural values, parenting, and child adjustment in the United States.

We examined whether cultural values, conformity and parenting behaviours were related to child adjustment in middle childhood in the United States. White, Black and Latino mothers (n = 273), fathers (n = 182) and their children (n = 272) reported on parental individualism and collectivism, conformity values, parental warmth, monitoring, family obligation expectations, and child internalising and externalising behaviours. Mean differences, bivariate correlations and multiple regression analyses were performed on variables of interest. Collectivism in mothers and fathers was associated with family obligation expectations and parental warmth. Fathers with higher conformity values had higher expectations of children's family obligations. Child internalising and externalising behaviours were greater when Latino families subscribed to individualistic values. These results are discussed in the context of cultural values, protective and promotive factors of behaviour, and race/ethnicity in the United States.

Racial and Ethnic Disparities in Peripheral Artery Disease.

Peripheral artery disease is an obstructive, atherosclerotic disease of the lower extremities causing significant morbidity and mortality. Black Americans are disproportionately affected by this disease while they are also less likely to be diagnosed and promptly treated. The consequences of this disparity can be grim as Black Americans bear the burden of lower extremity amputation resulting from severe peripheral artery disease. The risk factors of peripheral artery disease and how they differentially affect certain groups are discussed in addition to a review of pharmacological and nonpharmacological treatment modalities. The purpose of this review is to highlight health care inequities and provide a review and resource of available recommendations for clinical management of all patients with peripheral artery disease.

Comparing associations between personality and loneliness at midlife across three cultural groups.

OBJECTIVE: Loneliness represents a public health threat given its central role in predicting adverse mental and physical health outcomes. Prior research has established four of the Big Five personality traits as consistent cross-sectional predictors of loneliness in largely western, White samples. However, it is not clear if the personality predictors of loneliness vary across cultures. METHOD: The present study estimates associations between the Big Five traits and loneliness across distinct samples of White American, Black American, and Japanese adults (n = 6051 at T1). Confirmatory factor analysis and exploratory structural equation modeling were used to examine measurement invariance properties of the Big Five and loneliness across these groups. The factor structures were then carried forward to estimate associations between personality and loneliness across two assessments waves using structural equation modeling. RESULTS: While Neuroticism was a strong predictor across groups, low Extraversion was more predictive of loneliness in Japan than in the U.S., and low Conscientiousness was only a significant predictor in the U.S. CONCLUSIONS: Previous literature offers a framework for interpreting these findings in that loneliness may be shaped comparatively more through interconnectedness in Japanese culture, while, in the U.S., individual goals and personal romantic expectations are more salient.

Obstetric violence as immigration injustice: A view from the United States and Colombia.

In September 2020, Project South, along with numerous other organizations, released a report detailing abuses in a Georgia Detention Center - including forced hysterectomies. Whatever other factors are at play, one of them is an intrinsic connection between obstetric violence against pregnant migrants and immigration injustice. It is not incidental that these acts - in US detention centers, along the US-Mexico border, in Colombian hospitals and clinics - are being perpetrated on immigrant bodies. And it is not accidental or random which immigrant bodies are vulnerable to these violations. Understanding and confronting obstetric violence directed at pregnant migrants, though, requires reconceptualizing the nature of obstetric violence itself. In particular, we must recognize that obstetric violence against pregnant Latin American migrants in the United States and Colombia is a type of immigration injustice, a means to perpetrate immigration injustice, and a product of immigration injustice. As such, bioethicists need to collaborate with immigration scholars to resist it. After providing some background on the nature of obstetric violence and some ways it is perpetuated against pregnant migrants in the United States and Colombia, I will give a brief overview of how I conceptualize immigration justice. From there, I explain how this type of obstetric violence constitutes a type of immigration injustice, a means to perpetrate immigration injustice, and a product of immigration injustice. My hope is that this analysis motivates bioethicists throughout the Americas to engage with immigration scholars and activists to confront the issue more forcefully.

Epidemiology of HIV in the USA: epidemic burden, inequities, contexts, and responses.

The HIV epidemic in the USA began as a bicoastal epidemic focused in large cities but, over nearly four decades, the epidemiology of HIV has changed. Public health surveillance data can inform an understanding of the evolution of the HIV epidemic in terms of the populations and geographical areas most affected. We analysed publicly available HIV surveillance data and census data to describe: current HIV prevalence and new HIV diagnoses by region, race or ethnicity, and age; trends in HIV diagnoses over time by HIV acquisition risk and age; and the distribution of HIV prevalence by geographical area. We reviewed published literature to explore the reasons for the current distribution of HIV cases and important disparities in HIV prevalence. We identified opportunities to improve public health surveillance systems and uses of data for planning and monitoring public health responses. The current US HIV epidemic is marked by geographical concentration in the US South and profound disparities between regions and by race or ethnicity. Rural areas vary in HIV prevalence; rural areas in the South are more likely to have a high HIV prevalence than rural areas in other US Census regions. Ongoing disparities in HIV in the South are probably driven by the restricted expansion of Medicaid, health-care provider shortages, low health literacy, and HIV stigma. HIV diagnoses overall declined in 2009-18, but HIV diagnoses among individuals aged 25-34 years increased during the same period. HIV diagnoses decreased for all risk groups in 2009-18; among men who have sex with men (MSM), new diagnoses decreased overall and for White MSM, remained stable for Black MSM, and increased for Hispanic or Latino MSM. Surveillance data indicate profound and ongoing disparities in HIV cases, with disproportionate impact among people in the South, racial or ethnic minorities, and MSM.

The opioid crisis and HIV in the USA: deadly synergies.

The opioid epidemic is one of the greatest public health problems that the USA faces. Opioid overdose death rates have increased steadily for more than a decade and doubled in 2013-17, as the highly potent synthetic opioid fentanyl entered the drug supply. Demographics of new HIV diagnoses among people who inject drugs are also changing, with more new HIV diagnoses occurring among White people, young people (aged 13-34 years), and people who reside outside large central metropolitan areas. Racial differences also exist in syringe sharing, which decreased among Black people and Hispanic people but remained unchanged among White people in 2005-15. Recent HIV outbreaks have occurred in rural areas of the USA, as well as among marginalised people in urban areas with robust HIV prevention and treatment services (eg, Seattle, WA). Multiple evidence-based interventions can effectively treat opioid use disorder and prevent HIV acquisition. However, considerable barriers exist precluding delivery of these solutions to many people who inject drugs. If the USA is serious about HIV prevention among this group, stigma must be eliminated, discriminatory policies must change, and comprehensive health care must be accessible to all. Finally, root causes of the opioid epidemic such as hopelessness need to be identified and addressed.

Decreased Racial and Ethnic Disparities in Emergency Department Wait Time in the United States.

BACKGROUND: Previous data over an extended period indicated that Black and Hispanic patients waited significantly longer than their White counterparts to see a qualified practitioner in US emergency departments (EDs). OBJECTIVE: The objective of this study was to assess recent trends and sources of racial and ethnic disparities in patient wait time to see a qualified practitioner in US EDs. DATA SOURCES: Publicly available ED subsample of the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2003-2017. RESEARCH DESIGN: A retrospective cross-sectional analysis of a nationally representative sample of visits to US EDs from 2003 to 2017. Joinpoint statistical analysis and survey-weighted regression were used to assess changes in ED wait time by race/ethnic group over time. PRINCIPAL FINDINGS: For non-Hispanic White patients, median ED wait time increased annually by 1.3 minutes from 2003 through 2008, decreased by 3.0 minutes from 2008 through 2012, and decreased by 1.7 minutes from 2012 to 2017. For non-Hispanic Black patients, median wait time increased annually by 2.0 minutes from 2003 through 2008, decreased by 3.8 minutes from 2008 through 2015, and remained fairly unchanged from 2015 through 2017. For Hispanic patients, the trend in median wait time remained statistically unchanged from 2003 through 2009. It decreased by annually by 4.7 minutes from 2009 to 2012 and by 1.5 minutes from 2012 through 2017. By the end of 2017, median ED wait time decreased to under 20 minutes across all 3 groups. CONCLUSIONS: Over time, ED wait times decreased to under 20 minutes across all racial and ethnic groups between 2003 and 2017. Observed disparities were largely the result of where minority populations accessed care and disappeared over time.

Association Between Social Vulnerability and Rates of HIV Diagnoses Among Black Adults, by Selected Characteristics and Region of Residence - United States, 2018.

During 2018, Black or African American (Black) persons accounted for 43% of all new diagnoses of HIV infection in the United States (1). The annual diagnosis rate (39.2 per 100,000 persons) among Black persons was four times the rate among all other racial/ethnic groups combined, indicating a profound disparity in HIV diagnoses (1,2). Community-level social and structural factors, such as social vulnerability, might help explain the higher rate of HIV diagnoses among Black persons. Social vulnerability refers to the potential negative health effects on communities caused by external stresses (3). CDC used National HIV Surveillance System (NHSS)* and Social Vulnerability Index (SVI)† data to examine the association between diagnosed HIV infections and social vulnerability among Black adults aged ≥18 years. Black adults in communities in the highest quartile of SVI were 1.5 times (rate ratio [RR] = 1.5; 95% CI = 1.4-1.6) as likely to receive a diagnosis of HIV infection as were those in communities in the lowest quartile. Because of a history of racial discrimination and residential segregation, some Black persons in the United States reside in communities with the highest social vulnerability (4,5), and this finding is associated with experiencing increased risk for HIV infection. The development and prioritization of interventions that address social determinants of health (i.e., the conditions in which persons are born, grow, live, work, and age), are critical to address the higher risk for HIV infection among Black adults living in communities with high levels of social vulnerability. Such interventions might help prevent HIV transmission and reduce disparities among Black adults.

Indifference to dissonance in native Amazonians reveals cultural variation in music perception.

by biology remains debated. One widely discussed phenomenon is that some combinations of notes are perceived by Westerners as pleasant, or consonant, whereas others are perceived as unpleasant,or dissonant. The contrast between consonance and dissonance is central to Western music and its origins have fascinated scholars since the ancient Greeks. Aesthetic responses to consonance are commonly assumed by scientists to have biological roots, and thus to be universally present in humans. Ethnomusicologists and composers, in contrast, have argued that consonance is a creation of Western musical culture. The issue has remained unresolved, partly because little is known about the extent of cross-cultural variation in consonance preferences. Here we report experiments with the Tsimane'--a native Amazonian society with minimal exposure to Western culture--and comparison populations in Bolivia and the United States that varied in exposure to Western music. Participants rated the pleasantness of sounds. Despite exhibiting Western-like discrimination abilities and Western-like aesthetic responses to familiar sounds and acoustic roughness, the Tsimane' rated consonant and dissonant chords and vocal harmonies as equally pleasant. By contrast, Bolivian city- and town-dwellers exhibited significant preferences for consonance,albeit to a lesser degree than US residents. The results indicate that consonance preferences can be absent in cultures sufficiently isolated from Western music, and are thus unlikely to reflect innate biases or exposure to harmonic natural sounds. The observed variation in preferences is presumably determined by exposure to musical harmony, suggesting that culture has a dominant role in shaping aesthetic responses to music.

Racial Segregation and Respiratory Outcomes among Urban Black Residents with and at Risk of Chronic Obstructive Pulmonary Disease.

Rationale: Racial residential segregation has been associated with worse health outcomes, but the link with chronic obstructive pulmonary disease (COPD) morbidity has not been established.Objectives: To investigate whether racial residential segregation is associated with COPD morbidity among urban Black adults with or at risk of COPD.Methods: Racial residential segregation was assessed using isolation index, based on 2010 decennial census and baseline address, for Black former and current smokers in the multicenter SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study), a study of adults with or at risk for COPD. We tested the association between isolation index and respiratory symptoms, physiologic outcomes, imaging parameters, and exacerbation risk among urban Black residents, adjusting for established COPD risk factors, including smoking. Additional mediation analyses were conducted for factors that could lie on the pathway between segregation and COPD outcomes, including individual and neighborhood socioeconomic status, comorbidity burden, depression/anxiety, and ambient pollution.Measurements and Main Results: Among 515 Black participants, those residing in segregated neighborhoods (i.e., isolation index ⩾0.6) had worse COPD Assessment Test score (ß = 2.4; 95% confidence interval [CI], 0.7 to 4.0), dyspnea (modified Medical Research Council scale; ß = 0.29; 95% CI, 0.10 to 0.47), quality of life (St. George's Respiratory Questionnaire; ß = 6.1; 95% CI, 2.3 to 9.9), and cough and sputum (ß = 0.8; 95% CI, 0.1 to 1.5); lower FEV1% predicted (ß = -7.3; 95% CI, -10.9 to -3.6); higher rate of any and severe exacerbations; and higher percentage emphysema (ß = 2.3; 95% CI, 0.7 to 3.9) and air trapping (ß = 3.8; 95% CI, 0.6 to 7.1). Adverse associations attenuated with adjustment for potential mediators but remained robust for several outcomes, including dyspnea, FEV1% predicted, percentage emphysema, and air trapping.Conclusions: Racial residential segregation was adversely associated with COPD morbidity among urban Black participants and supports the hypothesis that racial segregation plays a role in explaining health inequities affecting Black communities.

Characterizing the cultural niches of North American birds.

Efforts to mitigate the current biodiversity crisis require a better understanding of how and why humans value other species. We use Internet query data and citizen science data to characterize public interest in 621 bird species across the United States. We estimate the relative popularity of different birds by quantifying how frequently people use Google to search for species, relative to the rates at which they are encountered in the environment. In intraspecific analyses, we also quantify the degree to which Google searches are limited to, or extend beyond, the places in which people encounter each species. The resulting metrics of popularity and geographic specificity of interest allow us to define aspects of relationships between people and birds within a cultural niche space. We then estimate the influence of species traits and socially constructed labels on niche positions to assess the importance of observations and ideas in shaping public interest in birds. Our analyses show clear effects of migratory strategy, color, degree of association with bird feeders, and, especially, body size on niche position. They also indicate that cultural labels, including "endangered," "introduced," and, especially, "team mascot," are strongly associated with the magnitude and geographic specificity of public interest in birds. Our results provide a framework for exploring complex relationships between humans and other species and enable more informed decision-making across diverse bird conservation strategies and goals.

A candidate gene analysis and GWAS for genes associated with maternal nondisjunction of chromosome 21.

Human nondisjunction errors in oocytes are the leading cause of pregnancy loss, and for pregnancies that continue to term, the leading cause of intellectual disabilities and birth defects. For the first time, we have conducted a candidate gene and genome-wide association study to identify genes associated with maternal nondisjunction of chromosome 21 as a first step to understand predisposing factors. A total of 2,186 study participants were genotyped on the HumanOmniExpressExome-8v1-2 array. These participants included 749 live birth offspring with standard trisomy 21 and 1,437 parents. Genotypes from the parents and child were then used to identify mothers with nondisjunction errors derived in the oocyte and to establish the type of error (meiosis I or meiosis II). We performed a unique set of subgroup comparisons designed to leverage our previous work suggesting that the etiologies of meiosis I and meiosis II nondisjunction differ for trisomy 21. For the candidate gene analysis, we selected genes associated with chromosome dynamics early in meiosis and genes associated with human global recombination counts. Several candidate genes showed strong associations with maternal nondisjunction of chromosome 21, demonstrating that genetic variants associated with normal variation in meiotic processes can be risk factors for nondisjunction. The genome-wide analysis also suggested several new potentially associated loci, although follow-up studies using independent samples are required.