Examination of MGMT as a risk gene for dementia in the Amish.

Introduction: Recently, the O-6-methylguanine-DNA methyltransferase (MGMT) locus was proposed as influencing the risk of Alzheimer's disease (AD) in women who did not carry the apolipoprotein E ε4 allele. We examined an Amish founder population for any influence of genetic variation in and around the MGMT locus on the risk for dementia.

Methods: Genetic association was performed for single nucleotide polymorphisms (SNPs) surrounding the MGMT locus.

Diverse ancestry GWAS for advanced age-related macular degeneration in TOPMed-imputed and Ophthalmologically-confirmed 16,108 cases and 18,038 controls.

Age-related macular degeneration (AMD) is a leading cause of blindness with $344 billion dollars global costs. In 2016, the International Age-related Macular Degeneration Genomics Consortium devised genomic data on ∼50,000 individuals (IAMDGC 1.0) and identified 52 variants across 34 loci associated with advanced AMD in European ancestry.

Identifying X-chromosome variants associated with age-related macular degeneration.

Purpose: In genome-wide association studies (GWAS), X chromosome (ChrX) variants are often not investigated. Sex-specific effects and ChrX-specific quality control (QC) are needed to examine these effects. Previous GWAS identified 52 autosomal variants associated with age-related macular degeneration (AMD) via the International AMD Genomics Consortium (IAMDGC), but did not analyze ChrX.

Asian Cohort for Alzheimer's Disease (ACAD) pilot study on genetic and non-genetic risk factors for Alzheimer's disease among Asian Americans and Canadians.

Introduction: Clinical research in Alzheimer's disease (AD) lacks cohort diversity despite being a global health crisis. The Asian Cohort for Alzheimer's Disease (ACAD) was formed to address underrepresentation of Asians in research, and limited understanding of how genetics and non-genetic/lifestyle factors impact this multi-ethnic population.

Methods: The ACAD started fully recruiting in October 2021 with one central coordination site, eight recruitment sites, and two analysis sites.

Genome-wide association studies identify novel loci in rapidly progressive Alzheimer's disease.

Introduction: Recent data suggest that distinct prion-like amyloid beta and tau strains are associated with rapidly progressive Alzheimer's disease (rpAD). The role of genetic factors in rpAD is largely unknown.

Methods: Previously known AD risk loci were examined in rpAD cases.

Genetic analysis of cognitive preservation in the midwestern Amish reveals a novel locus on chromosome 2.

Introduction: Alzheimer disease (AD) remains a debilitating condition with limited treatments and additional therapeutic targets needed. Identifying AD protective genetic loci may identify new targets and accelerate identification of therapeutic treatments. We examined a founder population to identify loci associated with cognitive preservation into advanced age.

Founder population-specific weights yield improvements in performance of polygenic risk scores for Alzheimer disease in the Midwestern Amish.

Alzheimer disease (AD) is the most common type of dementia and is estimated to affect 6 million Americans. Risk for AD is multifactorial, including both genetic and environmental risk factors. AD genomic research has generally focused on identification of risk variants.

Identifying X-Chromosome Variants Associated with Age-Related Macular Degeneration.

Purpose: In genome-wide association studies (GWAS), X chromosome (ChrX) variants are often not investigated. Sex-specific effects and ChrX-specific quality control (QC) are needed to examine these effects. Previous analyses identified 52 autosomal variants associated with age-related macular degeneration (AMD) via the International AMD Genomics Consortium (IAMDGC), but did not analyze ChrX.

Neuropsychiatric features in a multi-ethnic population with Alzheimer disease and mild cognitive impairment.

Background: Alzheimer disease (AD) is more prevalent in African American (AA) and Hispanic White (HIW) compared to Non-Hispanic White (NHW) individuals. Similarly, neuropsychiatric symptoms (NPS) vary by population in AD. This is likely the result of both sociocultural and genetic ancestral differences.

Visuospatial and Verbal Memory Differences in Amish Individuals With Alzheimer Disease and Related Dementias.

Background: Verbal and visuospatial memory impairments are common to Alzheimer disease and Related Dementias (ADRD), but the patterns of decline in these domains may reflect genetic and lifestyle influences. The latter may be pertinent to populations such as the Amish who have unique lifestyle experiences.

Methods: Our data set included 420 Amish and 401 CERAD individuals.

Consequences of a Rare Complement Factor H Variant for Age-Related Macular Degeneration in the Amish.

Purpose: Genetic variants in the complement factor H gene (CFH) have been consistently implicated in age-related macular degeneration (AMD) risk. However, their functional effects are not fully characterized. We previously identified a rare, AMD-associated variant in CFH (P503A, rs570523689) in 19 Amish individuals, but its functional consequences were not investigated.

Genomewide Association Study of Retinal Traits in the Amish Reveals Loci Influencing Drusen Development and Link to Age-Related Macular Degeneration.

Purpose: The purpose of this study was to identify genetic risk loci for retinal traits, including drusen, in an Amish study population and compare these risk loci to known risk loci of age-related macular degeneration (AMD).

Methods: Participants were recruited from Amish communities in Ohio, Indiana, and Pennsylvania. Each participant underwent a basic health history, ophthalmologic examination, and genotyping.

Including diverse and admixed populations in genetic epidemiology research.

The inclusion of ancestrally diverse participants in genetic studies can lead to new discoveries and is important to ensure equitable health care benefit from research advances. Here, members of the Ethical, Legal, Social, Implications (ELSI) committee of the International Genetic Epidemiology Society (IGES) offer perspectives on methods and analysis tools for the conduct of inclusive genetic epidemiology research, with a focus on admixed and ancestrally diverse populations in support of reproducible research practices. We emphasize the importance of distinguishing socially defined population categorizations from genetic ancestry in the design, analysis, reporting, and interpretation of genetic epidemiology research findings.

The genetic architecture of Alzheimer disease risk in the Ohio and Indiana Amish.

Alzheimer disease (AD) is the most common type of dementia and is currently estimated to affect 6.2 million Americans. It ranks as the sixth leading cause of death in the United States, and the proportion of deaths due to AD has been increasing since 2000, while the proportion of many other leading causes of deaths have decreased or remained constant.

Genetic variants in the SHISA6 gene are associated with delayed cognitive impairment in two family datasets.

Introduction: Studies of cognitive impairment (CI) in Amish communities have identified sibships containing CI and cognitively unimpaired (CU) individuals. We hypothesize that CU individuals may carry protective alleles delaying age at onset (AAO) of CI.

Methods: A total of 1522 individuals screened for CI were genotyped.

Familial Segregation of Venous Thromboembolism in Sweden: A Nationwide Family Study of Heritability and Complex Segregation Analysis.

Background This is the first nationwide segregation analysis that aimed to determine whether familial venous thromboembolism (VTE) is attributable to inheritance and/or shared environment, and the possible mode of inheritance. Methods and Results The Swedish Multi-Generation Register was linked to the Swedish patient register for the period 1964 to 2015. Three generational families of Swedish-born individuals were identified.

The GGLEAM Study: Understanding Glaucoma in the Ohio Amish.

Glaucoma leads to millions of cases of visual impairment and blindness around the world. Its susceptibility is shaped by both environmental and genetic risk factors. Although over 120 risk loci have been identified for glaucoma, a large portion of its heritability is still unexplained.

Rare variants and loci for age-related macular degeneration in the Ohio and Indiana Amish.

Age-related macular degeneration (AMD) is a leading cause of blindness in the world. While dozens of independent genomic variants are associated with AMD, about one-third of AMD heritability is still unexplained. To identify novel variants and loci for AMD, we analyzed Illumina HumanExome chip data from 87 Amish individuals with early or late AMD, 79 unaffected Amish individuals, and 15 related Amish individuals with unknown AMD affection status.

Genetic Correlations Between Diabetes and Glaucoma: An Analysis of Continuous and Dichotomous Phenotypes.

Purpose: A genetic correlation is the proportion of phenotypic variance between traits that is shared on a genetic basis. Here we explore genetic correlations between diabetes- and glaucoma-related traits.

Design: Cross-sectional study.

Algorithm to Estimate the Extended Turnaround Time Including Outpatient Waiting Time for Blood Specimen Collection when a Stand-alone Queue Ticket System not Connectable to Laboratory Information System Is Used.

Background: A queue ticket system (QTS) used in an outpatient phlebotomy clinic was unable to be directly integrated with the laboratory information system (LIS). To monitor patient's waiting time and extended turnaround time (TAT) as patient-centered quality indicators for outpatient laboratory services, we developed an algorithm to integrate data between the QTS and the LIS.

Methods: Between June 1 to September 30, 2017, data files were exported from a QSYS-8000 (HION Tech, Seoul, Korea).

Genome-wide analyses identify 68 new loci associated with intraocular pressure and improve risk prediction for primary open-angle glaucoma.

Glaucoma is the leading cause of irreversible blindness globally . Despite its gravity, the disease is frequently undiagnosed in the community . Raised intraocular pressure (IOP) is the most important risk factor for primary open-angle glaucoma (POAG).

AMISH EYE STUDY: Baseline Spectral Domain Optical Coherence Tomography Characteristics of Age-Related Macular Degeneration.

Purpose: To describe spectral domain optical coherence tomography (SD-OCT) findings in an Amish cohort to assess SD-OCT markers for early age-related macular degeneration (AMD).

Methods: The authors performed a family-based prospective cohort study of 1,146 elderly Amish subjects (age range 50-99 years) (2,292 eyes) who had a family history of at least 1 individual with AMD. All subjects underwent complete ophthalmic examinations, SD-OCT using both Cirrus and Spectralis (20 × 20° scan area) instruments, fundus autofluorescence, infrared imaging, and color fundus photography.

ONETOOL for the analysis of family-based big data.

Motivation: Despite the need for separate tools to analyze family-based data, there are only a handful of tools optimized for family-based big data compared to the number of tools available for analyzing population-based data.

Results: ONETOOL implements the properties of well-known existing family data analysis tools and recently developed methods in a computationally efficient manner, and so is suitable for analyzing the vast amount of variant data available from sequencing family members, providing a rich choice of analysis methods for big data on families.

Availability And Implementation: ONETOOL is freely available from http://healthstat.