Genetic variants and risk of asthma in an American Indian population

Asthma and Obstructive Sleep Apnea Overlap in a Sample of Older American Indian Adults: The Strong Heart Study

Study Objectives: Our study aimed to investigate the association between asthma and obstructive sleep apnea (OSA) in American Indian communities, a historically underrepresented population in clinical research with a high prevalence of asthma and OSA risk factors like smoking and obesity. Methods: This cross-sectional study used data retrieved from the Strong Heart Study cohort. Participants who attended both the Asthma Sub-study and the Sleep Heart Health Study around the same time were compared for active asthma diagnosis, OSA diagnosis, and potential risk factors for asthma and OSA. The association between asthma and OSA was then evaluated. Results: Among the 2480 participants who attended the Strong Heart Study Phase III exam, 123 participated in both the Asthma Sub-study and the Sleep Heart Health Study. Of these, 13 were diagnosed with OSA, with 4 having moderate to severe OSA. There was no statistically significant difference in OSA prevalence between the active asthma group and the non-active asthma group (former asthma or no asthma) (9.6% vs. 12.5%, p = 0.63). Additionally, body mass index did not differ significantly between participants with both active asthma and OSA and those without active asthma, OSA, or both. OSA diagnosis was significantly associated with male sex (Odds Ratio [OR] 9.2 [1.85-45.87], p = 0.007) and body mass index (OR 1.1 [1.02-1.26], p = 0.016) but not with age or a diagnosis of active asthma. Conclusions: In this American Indian cohort, no significant difference in OSA prevalence was observed between participants with and without active asthma, contradicting previous studies. Further research is needed to explore the underlying reasons for this discrepancy.

Indigenous data governance approaches applied in research using routinely collected health data: a scoping review

Globally, there is a growing acknowledgment of Indigenous Peoples' rights to control data related to their communities. This is seen in the development of Indigenous Data Governance standards. As health data collection increases, it's crucial to apply these standards in research involving Indigenous communities. Our study, therefore, aims to systematically review research using routinely collected health data of Indigenous Peoples, understanding the Indigenous Data Governance approaches and the associated advantages and challenges. We searched electronic databases for studies from 2013 to 2022, resulting in 85 selected articles. Of these, 65 (77%) involved Indigenous Peoples in the research, and 60 (71%) were authored by Indigenous individuals or organisations. While most studies (93%) provided ethical approval details, only 18 (21%) described Indigenous guiding principles, 35 (41%) reported on data sovereignty, and 28 (33%) addressed consent. This highlights the increasing focus on Indigenous Data Governance in utilising health data. Leveraging existing data sources in line with Indigenous data governance principles is vital for better understanding Indigenous health outcomes.

Return of Participants' Incidental Genetic Research Findings: Experience from a Case-Control Study of Asthma in an American Indian Community

The proper communication of clinically actionable findings to participants of genetic research entails important ethical considerations, but has been challenging for a variety of reasons. We document an instance of the return of individual genetic results in the context of a very rural American Indian community, in hopes of providing insight to other investigators about potentially superior or inferior courses of action. This was a case/control study of asthma among 324 pediatric participants. Subsequently, microarray genotype data became available, providing over 2 million variants, incidentally including some conferring risk for conditions for which the American College of Medical Genetics recommends return of results. The study investigators engaged in extensive consultation with the IRB, the tribal government, and local clinicians to better inform our approach. We were able to notify the two participants heterozygous for the one clinically actionable variant identified. One participant welcomed this information and proceeded to obtain further clinical work-up; the other participant declined further follow-up. While demanding considerable time and effort, the return of clinically actionable genetic results is important from both an ethical perspective and to provide an improved trust relationship with the community of research participants.

Genomics and inclusion of Indigenous peoples in high income countries

Genomics research related to Indigenous people has been at worst exploitative and at best, retrospectively on a journey to improve effective engagement of Indigenous individuals and communities. Genomics can positively impact all stages of clinical management, and to improve genomic effectiveness researchers aggregate genomic data from diverse global sub-populations, such as shared ancestry groupings, as people within these groupings will have a greater proportion of shared DNA traits. While genomics is already being used worldwide to improve lives, its utility and effectiveness has not been maximized for individuals with Indigenous ancestry. Several large datasets of human genetic variation have been made publicly available, of which the most widely used is the Genome Aggregation Database (gnomAD), but none of these databases currently contain any population-specific data for Indigenous populations. There are many reasons why Indigenous people have been largely left out of genomics research and, because of this, miss out on the benefits offered. It is also clear that if research is to be effective, it needs to be done 'with' and not 'on' Indigenous communities. This systematic review of the literature regarding Indigenous peoples (in high income countries) and genomics aims to review the existing literature and identify areas of strength and weakness in study design and conduct, focusing on the effectiveness of Indigenous community engagement.

SNPs, adipokynes and adiposity in children with asthma

OBJECTIVES

Asthma and obesity are complex disorders influenced by environmental and genetic factors. We performed an integrative review of genetic polymorphisms and adipokines effects in children and adolescents with asthma and obesity.

DATA SOURCES

Articles focused on these issues were collected from SciELO, PubMed, LILACS, Embase and ScienceDirect electronic databases, in 2009-2020 period.

STUDY SELECTIONS

22 articles were selected, including clinical trials, analyses approaches, case-control studies, meta-analysis and Mendelian randomization studies.

RESULTS

Leptin concentrations were higher in obesity and asthma. The high value of BMI and Leptin indicated severe asthma. Adiponectin may be reduced in obese children. The high value of BMI and low level of Adiponectin may indicate severe asthma. Some linkage of PRKCA gene, asthma and BMI was observed. FTO T allele rs62048379 was positively associated with overweight/obesity, related to protein and PUFA:SFA ratio intake and influences the choice of more energy-dense foods. FTO rs9939609 effects are more pronounced among children with insufficient vitamin D levels.

CONCLUSION

Leptin may be a potential predictor for asthma control in children. BMI and Adiponectin could have certain predictive value for asthma. FTO gene was related to a higher mean BMI Z-score and accelerated developmental age per allele. Strong genetic heterogeneity influencing on asthma and obesity susceptibilities is evident and related to distinct genetic features. GWAS with childhood obesity in asthma contributed to greater insights, mainly on later childhood. Standardized definitions for asthma and overweight/obesity in studies approaching adipokines and SNPs would provide stronger evidence in deciding the best management.

Return of Participants' Incidental Genetic Research Findings: Experience from a Case-Control Study of Asthma in an American Indian Community

PURPOSE

The proper communication of clinically actionable findings to participants of genetic research entails important ethical considerations, but has been challenging for a variety of reasons. We document an instance of return of individual genetic results in the context of a very rural American Indian community, in hopes of providing insight to other investigators about potentially superior or inferior courses of action.

METHODS

The original study was a case/control study of asthma among 324 pediatric participants. The study utilized a genotyping microarray assessing over 2 million variants, including one conferring risk for hypertrophic cardiomyopathy for which the American College of Medical Genetics recommends return of results to participants. The study investigators engaged in extensive consultation with the IRB, the Tribal government and local clinicians to better inform our approach.

RESULTS

With some difficulty we were able to notify the 2 participants heterozygous for this variant. One participant welcomed this information and proceeded to obtain further clinical work-up; the other participant declined further follow-up.

CONCLUSION

While demanding of considerable time and effort, the return of clinically actionable genetic results is important from both an ethical perspective and to provide an improved trust relationship with the community of research participants.

Efficacy and feasibility of the BREATHE asthma intervention with American Indian children: a randomized controlled trial

American Indian (AI) children experience significant disparities in asthma prevalence, severity, and burden of disease, yet few asthma education interventions are tested in this population. This study aimed to evaluate the efficacy and feasibility of the BREATHE intervention with parents and AI children, during a 3-year follow-up period (n = 108), using a randomized controlled design. Children with asthma identified by electronic medical records (EMR) were screened and matched with 2 controls. The intervention included an initial educational and 24 months of follow-up. The control group continued their usual care. The primary outcome was the frequency of EMR documented, emergency department (ED) visits or hospitalization for respiratory complaints. There was no statistical difference in mean primary outcomes (1.34 (1.98) vs 1.22 (1.95), - 0.88 to 0.63, 95% CI of the difference, p = 0.75), nor percent with any ED visit or hospitalization (29/53, 55% vs 30/55, 54%, p = 0.99) between the intervention or control groups respectively. After 365 days, there was a borderline significant difference in time to primary outcome. Although limited in power, the present study did not demonstrate a persistent effect of this intervention. We recommend that AI pediatric asthma interventions are culturally-designed, use feasible procedures, and repeat education at least every 12 months.

New Insights Relating Gasdermin B to the Onset of Childhood Asthma

Chromosome 17q12-q21 is the most replicated genetic locus for childhood-onset asthma. Polymorphisms in this locus containing ∼10 genes interact with a variety of environmental exposures in the home and outdoors to modify asthma risk. However, the functional basis for these associations and their linkages to the environment have remained enigmatic. Within this extended region, regulation of GSDMB (gasdermin B) expression in airway epithelial cells has emerged as the primary mechanism underlying the 17q12-q21 genome-wide association study signal. Asthma-associated SNPs influence the abundance of GSDMB transcripts as well as the functional properties of GSDMB protein in airway epithelial cells. GSDMB is a member of the gasdermin family of proteins, which regulate pyroptosis and inflammatory responses to microbial infections. The aims of this review are to synthesize recent studies on the relationship of 17q12-q21 SNPs to childhood asthma and the evidence pointing to GSDMB gene expression or protein function as the underlying mechanism and to explore the potential functions of GSDMB that may influence the risk of developing asthma during childhood.

Disparate Effects of Invasive Group A Streptococcus on Native Americans

Active surveillance of invasive group A Streptococcus (iGAS) disease indicates that its incidence in the US general population is low, but limited studies show rates for American Indians and Alaska Natives (AI/AN) are severalfold higher. Major disparities in rates of iGAS exist between Indigenous and non-Indigenous populations of Australia, New Zealand, and Canada, but much less is understood about iGAS among AI/AN in the United States. Although complex host-pathogen interactions influence the rates of iGAS, including strain variation and virulence, the number and type of concurrent conditions, and socioeconomic status, the relative contribution of each remains unclear. We highlight the poor correlation between the substantial effect of iGAS among Indigenous persons in industrialized countries and the current understanding of factors that influence iGAS disease in these populations. Prospective, large-scale, population-based studies of iGAS are needed that include AI/AN as a necessary first step to understanding the effects of iGAS.

Interweaving Between Genetic and Epigenetic Studies on Childhood Asthma

The cause and underlying mechanisms that contribute to asthma pathogenesis are not well known. Both genome- and epigenome-wide association studies have identified genes associated with asthma risk. It is unknown to what extent genes identified in these two types of studies overlap. Based on existing literature and the DisGeNET database, we extracted overlapping genes identified in genetic and epigenetic studies of childhood asthma. Through analyses of variance, we assessed whether DNA methylation (DNAm) at 5′-C-phosphate-G-3′ (CpGs) on the overlapping genes was associated with neighboring single-nucleotide polymorphisms (SNPs) within 1M base pairs (bps) and with low linkage disequilibrium (r² < 0.2) in the childhood asthma-related genes. In total, 285 genes from genetic studies and 226 genes from epigenetic studies were shown to be associated with asthma risk, of which six overlap. Of the six genes, 79 CpGs and 8229 unique neighboring SNPs (1M bps) were included in methylation quantitative loci (methQTL) assessment analyses. We tested the association of DNAm at each of the 79 CpG sites with its neighboring SNPs. After adjusting for multiple testing by controlling the false discovery rate to 0.05 when testing methQTL for each CpG site, we found statistically significant associations in three genes with their neighboring SNPs and identified 34 unique methQTLs. The rather limited overlap in genes between genetic and epigenetic studies on asthma and the absence of methQTL in some of the overlapping genes highlight a need to jointly, rather than independently, examine genetic and epigenetic effects on asthma risk to improve our understanding of the underlying mechanisms of asthma.