Genetic structure of California's elk: a legacy of extirpations,reintroductions, population expansions,and admixture

California, USA, is home to 3 subspecies of North American elk (Cervus canadensis): Roosevelt (C. c. roosevelti), Rocky Mountain (C. c. nelsoni), and tule (C. c. nannodes). Effective management requires a baseline understanding of each subspecies' range, admixture zones, and geographic patterns of genetic diversity. To address these questions, we genotyped 1,271 individual elk from California (n = 1,204) and reference populations of Rocky Mountain and Roosevelt elk from Nevada (n = 32) and Oregon (n = 35), USA. Using 19 polymorphic microsatellite loci, we detected admixture between Roosevelt and Rocky Mountain elk at a contact zone in northern California, and between Roosevelt and tule elk in north-coastal California and central-coastal California. We identified a genetically distinct population of Roosevelt elk in northwestern California, likely reflecting the remnant population that survived a large demographic decline from overhunting during the 1800s. Tule elk exhibited lower levels of heterozygosity (0.44 ± 0.03 [SD]) and allelic richness (2.9 ± 0.2) than Rocky Mountain (0.58 ± 0.05, 4.9 ± 0.4, respectively) and Roosevelt (0.50 ± 0.06, 4.4 ± 0.6, respectively) elk. Among tule elk populations, heterozygosity varied, with the lowest heterozygosity (0.23 ± 0.05) corresponding to the oldest enclosed herd used over the past century as a source of translocations. Among tule elk populations, genetic structure revealed several cases of successful and unsuccessful reintroduction or augmentation attempts. Results provide an essential baseline for future monitoring and decisions about harvest management, translocations to preserve genetic diversity, and landscape-level conservation planning to maintain, enhance, or obstruct connectivity of elk populations. Genome-wide sequencing and analyses are needed to quantify inbreeding absolutely and assess genetic load and the age of admixture where subspecies currently exchange genes.     

Isolation and characterization of microsatellite DNA markers from mangrove crab,Scylla paramamosain

The first five variable microsatellite DNA loci for mangrove crab, Scylla paramanosain, were developed. Allelic variation and other characteristics at these loci were examined in this species captured at the Urado Bay, Japan. The number of alleles per locus ranged from 24 to 44. The expected heterozygosity across loci ranged from 0.900 to 0.999 and probability of identity (P_I) ranged from 2.8 × 10^?3 to 1.7 × 10^?2. Therefore, these microsatellite markers could be useful for estimating effect of stock enhancement release and population genetic structure of mangrove crab.     

Characterization of 29 tetranucleotide microsatellite loci in black bear (Ursus americanus) for use in forensic and population applications

We developed 29 forensic quality tetranucleotide microsatellite loci for the identification of individual black bear (Ursus americanus). Allele number averaged 5.35 and ranged from 3 to 11. The eight markers selected for forensic use permit the identification and exclusion of individual bear with a probability of identity of approximately 8.1 × 10⁻⁸ (approximately one per 12 million).     

Genome-wide assessment reveals a significant association between ACSS3 and physical activity

Recent genetic studies have identified physical activity (PA)-susceptible loci in European ancestry subjects; however, due to considerable genetic differences, these findings are not likely extendable to East Asian populations. Therefore, the present study aimed to identify significantly associated PA-susceptible loci using genome-wide association studies (GWASs) with East Asian (EAS) subjects and to generalize the findings to European (EUR) ancestries. The mRNA levels of genes located near the genome-wide significantly associated single-nucleotide polymorphisms (SNP) were compared under PA and control conditions. Rs74937256, located in ACSS3 (chromosome 12), which primarily functions in skeletal muscle tissues, was identified as a genome-wide significant variant (P = 6.06 × 10⁻⁹) in EAS. Additionally, the rs2525840, also in ACSS3 satisfied the Bonferroni corrected significance (P = 3.77 × 10⁻⁵) in EUR. We found that rs74937256 is an expressed trait locus of ACSS3 (P = 10⁻⁴), and ACSS3 mRNA expression significantly differs after PA, based on PrediXcan (P = 7 × 10⁻⁸) and the gene expression omnibus database (P = 0.043).     

Paternity testing of wild black rockfish <Emphasis Type="Italic">Sebastes inermis</Emphasis> (brownish type) from the Seto Inland Sea of Japan

We developed four microsatellite DNA loci to test for multiple paternity of black rockfish, Sebastes inermis, from the Seto Inland Sea of Japan. All loci showed a high degree of polymorphism (number of alleles per locus = 10–14, expected heterozygosity = 0.80) and discriminating power (probability of identity index = 3.71 × 10⁻⁶, exclusion probability = 0.999) in unrelated wild specimens (n = 32). Genotypic assignment of five dams (109–220 mm in total length) and 50 embryos from each dam (n = 50) indicated that four dams were mated with a single sire. Only for one dam and three of her embryos we could not exclude multiple paternity.     

Cyclic pollen production in Cedrus deodara

Based on a seven-year study of pollen production and release in two different natural populations of Cedrus deodara from Garhwal Himalaya, India, we determined that pollen output follows a two-year cycle. Pollen productivity determinations considered various sources of variability, including the number of pollen strobili per branch, strobili per tree, microsporophylls per tree and pollen grains per tree. Each of these parameters revealed significant year-to-year and population effects. Microsporangium dehiscence took from 2.5 to 3.5 days. Maximum dehiscence was observed between 12:00 and 14:00 h, which coincides with diurnal highest temperature and lowest relative humidity. Annual production of pollen per tree varied from averages of 4.7 × 10⁹, 7.2 × 10⁹ and 5.1 × 10⁹ in years of low production, with alternate high years, producing 12.6 × 10⁹, 14.1 × 10⁹, 13.3 × 10⁹ and 14.0 × 10⁹ pollen grains per tree. Annual pollen production in individual trees of C. deodara ranged from 1.4 × 10⁹ to 22.3 × 10⁹.     

Survival and cause-specific mortality of female Rocky Mountain elk exposed to human activity

Animal populations are becoming increasingly exposed to human activity as human populations expand and demand for energy resources (e.g., coal, oil and natural gas) increases. We initiated this study to document survival and cause-specific mortality patterns of female Rocky Mountain elk (Cervus elaphus) exposed to increasing levels of human activity. We fitted 184 females with VHF or GPS collars over 4 years and used the Kaplan–Meier survival estimator to calculate annual survival rates. We used multinomial logistic regression to assess differences in cause-specific mortality and generalized linear mixed models to determine how probability of survival was structured during hunting season; both analyses examined a suite of 5 covariates (i.e., age, year, extent of space use, cover, and human footprint) as potentially influencing cause-specific mortality and survival probability. Annual probability of survival averaged 0.8 (±0.02 SE) over 4 years but averaged 0.91 (±0.03 SE) when harvest mortality was excluded, which was the most significant source of mortality in most years ( [`(x)] = 0.13 ±0.02 \textSE \bar{x} = 0.13 \pm 0.02\,{\text{SE}} ). We found no difference between cause-specific mortality sources relative to elk that survived during the hunting season (χ ₁₀² = 5.79, P = 0.832). The probability of a female surviving during hunting season was negatively influenced by age, year, extent of space use, cover, and human footprint. We found evidence that human activity may have influenced annual rates of natural survival (i.e., exclusive of hunting mortality) and probability of survival during the hunting season. We note that this study occurred largely on privately owned and managed residential and ranch land and focused on female elk; we acknowledge that survival rate and cause-specific patterns of mortality may vary as a function of land ownership (private vs. public), demographic status, and management and harvest practices. While temporal and spatial scales of 1 week may be sufficient to describe patterns of direct mortality during hunting season, broad temporal or spatial scale analyses may be needed to address natural mortality during other seasons.     

Hyperproduction of chitinase influences crystal toxin synthesis and sporulation of <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis>

Bacillus thuringiensis HD-73 was transformed with the endochitinase gene chiA74 under the control of a strong promoter (pcytA) and a 5′ mRNA stabilizing (STAB-SD) sequence (HD-73-pEBchiA74). Expression levels were compared with those observed from the wild type strain (HD-73) and the recombinant HD-73 strain expressing chiA74 under the control of its native promoter (HD-73-pEHchiA74). The chitinolytic activity of HD-73-pEBchiA74 was markedly elevated, being ~58- and 362-fold higher than, respectively, HD-73-pEHchiA74 and parental HD-73, representing the highest levels of chitinase expression in recombinant B. thuringiensis reported to date. Parasporal crystals measured under transmission electron microscopy showed that HD-73 produced crystals of 1.235 (±0.214) and 1.356 (±0.247) μm in length when the bacterium was grown in respectively, NBS and NBS with glucose. Otherwise, HD-73-pEBchiA74 synthesized crystals of 1.250 (±0.222) and 1.139 (±0.202) μm in length when cultivated in NBS and NBS with glucose, respectively, values that showed a diminution of ~10 and 20% compared with crystals produced by HD-73-pEHchiA74 grown under the same conditions. Comparison of viable spore counts per ml showed that HD-73-pEBchiA74 produced fewest viable spores (1.5 × 10⁹, 1.3 × 10⁹), compared to HD-73-pEHchiA74 (4.9 × 10⁹, 5.3 × 10⁹) and HD-73 (6.8 × 10⁹, 8.8 × 10⁹) when grown in NBS and NBS supplemented with glucose, respectively. No change in cellular protease activity was observed despite the overproduction of the chitinase.     

Four monoclonal antibodies against capsular polysaccharides of Neisseria meningitidis serogroups A,C, Y and W135: Its application in identity tests

Murine hybridoma monoclonal antibodies (MAbs) were produced against the capsular polysaccharide (CPs) of serogroups A, C, W₁₃₅ and Y meningococci (MenA, MenC, MenW, MenY) in order to develop immunological reagents for the identification of meningococcal polysaccharides. Each serogroup-specific MAb reacted with the CPs from its homologous serogroup only and did not react with CPs from the other three serogroups. The affinity constant (Ka) of the four MAbs measured by non-competitive ELISA was 6.62 × 10⁹, 2.76 × 10⁹, 1.48 × 10⁹ and 3.8 × 10⁹ M^?1 for MenA, MenC, MenW and MenY MAbs respectively. The application of these MAbs for identity tests was demonstrated by their abilities to correctly identify the CPs from serogroups A, C, W₁₃₅ and Y in meningococcal CPs-based vaccines through ELISA. The MAbs obtained in this work are a very valuable set of tools for study meningococcal polysaccharides vaccines.     

Flow‐injection determination of cysteine in pharmaceuticals based on luminol–persulphate chemiluminescence detection

A flow injection (FI) method is reported for the determination of l‐ cysteine, based on its enhancement on chemiluminescence (CL) emission of luminol oxidized by sodium persulphate in alkaline solution. The calibration graph was linear over the range 1.0 × 10^–9–5.0 × 10^–7 mol/L (r² = 0.9992), with relative standard deviations (RSDs) in the range 1.1–2.3% (n = 4). The limit of detection (3σ blank) was 5.0 × 10^–10 mol/L with a sample throughput of 120/h. The method was applied to pharmaceuticals and the results obtained were in reasonable agreement with the amount labelled. The proposed method was also applied to cysteine in synthetic amino acid mixtures. Calibration graphs of N‐acetylcysteine and glutathione over the range 1.0–50 × 10^–8 and 0.5–7.5 × 10^–7 mol/L were also established (r² = 0.998 and 0.9986) with RSDs in the range 1.0–2.0% (n = 4), and the limits of detection (3σ blank) were 5.0 × 10^–9 and 1.0 × 10^–8 mol/L, respectively. Copyright © 2008 John Wiley & Sons, Ltd.     

In Vitro Sensitivity of <Emphasis Type="Italic">Rhizobium</Emphasis> and Phosphate Solubilising Bacteria to Herbicides

Nitrogen fixing bacteria, rhizobia and phosphate solubilizing bacteria (PSB) are the commonly applied microbial inoculants in grain legumes (Pulses). It is important to apply herbicides to control weeds in order to augment yield of the crop. The herbicides may however, be incompatible with the microbial inoculants. This study compared the effect of the recommended pre-plant incorporated herbicide, fluchloralin (20.25 × 10⁴ ppm) and pre-emergence herbicide, pendimethalin in two doses (9 × 10⁴ and 15 × 10⁴ ppm) on the growth and survival of mungbean Rhizobium and PSB, under laboratory conditions. These herbicides were also used under field conditions in conjunction with biofertilizers (R, PSB) to improve grain yield of mungbean. It was found that fluchloralin (20.25 × 10⁴ ppm) and the lower dose of pendimethalin (9 × 10⁴ ppm) had no adverse effect on growth of Rhizobium and PSB. The higher dose of pendimethalin (15 × 10⁴ ppm) was safe on PSB but it imposed a retarding effect on the growth of Rhizobium.     

Abiotic,bottom-up,and top-down influences on recruitment of Rocky Mountain elk in Oregon: A retrospective analysis

Understanding the relative effects of the many factors that may influence recruitment of ungulates is fundamental to managing their populations. Over the last 4 decades, average recruitment in some populations of elk (Cervus elaphus) in Oregon, USA declined from >50 to <20 juveniles per 100 females, and several competing hypotheses address these declines. We developed a priori models and constructed covariates spanning 1977–2005 from hunter-killed elk, elk population estimates, cougar harvest, and weather statistics to evaluate abiotic, bottom-up, and top-down factors that may explain annual variation and long-term trends of pregnancy, juveniles-at-heel in late autumn, and recruitment of juvenile elk in spring. In models of pregnancy status, August precipitation, age, and cougar index had positive effects, whereas previous year (t − 1) winter severity or winter precipitation_(t−1) and elk density had negative effects. In models of juvenile-at-heel in late autumn, August precipitation, August precipitation_(t−1), cougar index × elk density_(t−1), and age had positive effects, whereas cougar index, elk density_(t−1), and winter precipitation_(t−1) had negative effects. Juvenile recruitment was best explained by positive effects of August precipitation_(t−1), lactation rate, and cougar index × elk density_(t−1) and negative effects of cougar index and elk density_(t−1). Winter severity, precipitation, and temperature were not significant in explaining variation in elk recruitment. Annual variation in pregnancy, juvenile-at-heel, and recruitment was most influenced by August precipitation, whereas long-term trends in recruitment were most influenced by cougar densities with relatively weak effects of elk density. These results provide insight into causes of year-to-year and long-term trends of elk recruitment and provide a basis for more rigorous evaluation of factors affecting recruitment of elk. © 2012 The Wildlife Society.     

Isolation and characterization of ten novel microsatellite loci in the red-winged tinamou (<Emphasis Type="Italic">Rhynchotus rufescens</Emphasis>, Tinamiformes,Aves) and cross-amplification in other tinamous

We describe the isolation and characterization of ten microsatellite loci from the red-winged tinamou (Rhynchotus rufescens) and also evaluated the cross-amplification of these loci and other ten loci previously developed for the great tinamou (Tinamus major) in other tinamous. Genetic variability was assessed using 24 individuals. Six loci were polymorphic with moderate to high number of alleles per locus (2–12 alleles) and showed expected heterozygosity (HE) ranging from 0.267 to 0.860. All loci conformed to the Hardy–Weinberg expectation and linkage disequilibrium was not significant for any pair of loci. This battery of polymorphic loci showed high paternity exclusion probability (0.986) and low genetic identity probability (4.95 × 10⁻⁵), proving to be helpful for parentage tests and population analyses in the red-winged tinamou. The cross-amplification was moderate where of the 160 locus/taxon combinations, 46 (28.75%) successfully amplified.     

Genome‐wide association study identifies variants in the CAPN9 gene associated with umbilical hernia in pigs

Pig umbilical hernia (UH) affects pig welfare and brings considerable economic loss to the pig industry. To date, the molecular mechanisms underlying pig UH are still poorly understood. To identify potential loci for susceptibility to this disease, we performed a genome‐wide association study in an Erhualian × Shaziling F₂ intercross population. A total of 45 animals were genotyped using Illumina Porcine SNP60 BeadChips. We observed a SNP (rs80993347) located in the calpain‐9 (CAPN9) gene on Sus scrofa chromosome 14 that was significantly associated with UH (P = 1.97 × 10^?10). Then, we identified a synonymous mutation rs321865883 (g.20164T>C) in exon 10 of the CAPN9 gene that distinguished two affected individuals (CC) from their normal full‐sibs (TC). Finally, quantitative polymerase chain reaction was explored to investigate the mRNA expression profile of the CAPN9 gene in 12 tissues in Yorkshire pigs at different developmental stages (3, 90 and 180 days). CAPN9 showed high expression levels in the gastrointestinal tract at these three growth stages. The results of this study indicate that the CAPN9 gene might be implicated in UH. Further studies are required to establish a role of CAPN9 in pig UH.     

Optimization of novel polymorphic microsatellites in the endangered Sumatran rhinoceros (Dicerorhinus sumatrensis)

Loss of habitat and poaching have led to a drastic reduction in numbers of the Sumatran rhinoceros (Dicerorhinus sumatrensis). To aid in the conservation management of this species, we isolated and optimized 10 polymorphic Sumatran rhinoceros microsatellite loci. A survey of six individuals yielded a mean number of alleles of 3.7, mean expected heterozygosity of 0.551 and probability of identity of 3.46 × 10^?8. Although this estimate is similar to estimates of microsatellite variability in the Black, Indian and White rhinoceroses, such a conclusion is premature as locus purity, sample size and number of loci surveyed vary significantly among studies.     

Use of Real-Time PCR Technique in Studying Rumen Cellulolytic Bacteria Population as Affected by Level of Roughage in Swamp Buffalo

A real-time polymerase chain reaction approach was used in this study to determine the population of major ruminal bacterial species (Fibrobacter succinogenes, Ruminococcus albus, and Ruminococcus flavefaciens) in digesta and rumen fluid of swamp buffalo (Bubalus bubalis). Four rumen-fistulated, male swamp buffalo were randomly assigned according to a 4 × 4 Latin square design to evaluate the effect of the urea-treated rice straw (roughage source)-to-concentrate ratio on cellulolytic bacterial distribution. Animals were fed roughage-to-concentrate (R:C) ratios of 100:0, 75:25, 50:50, and 25:75, respectively. At the end of each period, rumen fluid and digesta were collected at 0 h and 4 h post-morning-feeding. It was found that feeding urea-treated rice straw solely increased these three cellulolytic bacteria numbers up to 2.65 × 10⁹ and 3.54 × 10⁹ copies per milliliter for F. succinogenes, 5.10 × 10⁷ and 7.40 × 10⁷ copies per millilter for R. Flavefaciens, and 4.00 × 10⁶ and 6.00 × 10⁶ copies per milliliter for R. albus in rumen fluid and digesta, respectively. The distribution of the three cellulolytic bacteria species in digesta were highest at 3.21 × 10⁹, 4.55 × 10⁷, and 4.56 × 10⁶ copies per milliliter for F. succinogenes, R. flavefaciens, and R. albus, respectively. Moreover, at 4 h post-morning-feeding, the populations of the three cellulolytic bacteria were higher than found at 0 h post-morning-feeding. It is most notable that F. succinogenes were the highest in population in the rumen of swamp buffalo and cellulolytic bacteria mostly adhered to feed digesta in the rumen.     

CpG‐related SNPs in the MS4A region have a dose‐dependent effect on risk of late–onset Alzheimer disease

CpG‐related single nucleotide polymorphisms (CGS) have the potential to perturb DNA methylation; however, their effects on Alzheimer disease (AD) risk have not been evaluated systematically. We conducted a genome‐wide association study using a sliding‐window approach to measure the combined effects of CGSes on AD risk in a discovery sample of 24 European ancestry cohorts (12,181 cases, 12,601 controls) from the Alzheimer's Disease Genetics Consortium (ADGC) and replication sample of seven European ancestry cohorts (7,554 cases, 27,382 controls) from the International Genomics of Alzheimer's Project (IGAP). The potential functional relevance of significant associations was evaluated by analysis of methylation and expression levels in brain tissue of the Religious Orders Study and the Rush Memory and Aging Project (ROSMAP), and in whole blood of Framingham Heart Study participants (FHS). Genome‐wide significant (p < 5 × 10^?8) associations were identified with 171 1.0 kb‐length windows spanning 932 kb in the APOE region (top p < 2.2 × 10^?308), five windows at BIN1 (top p = 1.3 × 10^?13), two windows at MS4A6A (top p = 2.7 × 10^?10), two windows near MS4A4A (top p = 6.4 × 10^?10), and one window at PICALM (p = 6.3 × 10^‐9). The total number of CGS‐derived CpG dinucleotides in the window near MS4A4A was associated with AD risk (p = 2.67 × 10^?10), brain DNA methylation (p = 2.15 × 10^?10), and gene expression in brain (p = 0.03) and blood (p = 2.53 × 10^?4). Pathway analysis of the genes responsive to changes in the methylation quantitative trait locus signal at MS4A4A (cg14750746) showed an enrichment of methyltransferase functions. We confirm the importance of CGS in AD and the potential for creating a functional CpG dosage‐derived genetic score to predict AD risk.     

Haplotypic analysis of Wellcome Trust Case Control Consortium data

We applied a recently developed multilocus association testing method (localized haplotype clustering) to Wellcome Trust Case Control Consortium data (14,000 cases of seven common diseases and 3,000 shared controls genotyped on the Affymetrix 500 K array). After rigorous data quality filtering, we identified three disease-associated loci with strong statistical support from localized haplotype cluster tests but with only marginal significance in single marker tests. These loci are chromosomes 10p15.1 with type 1 diabetes (p = 5.1 × 10⁻⁹), 12q15 with type 2 diabetes (p = 1.9 × 10⁻⁷) and 15q26.2 with hypertension (p = 2.8 × 10⁻⁸). We also detected the association of chromosome 9p21.3 with type 2 diabetes (p = 2.8 × 10⁻⁸), although this locus did not pass our stringent genotype quality filters. The association of 10p15.1 with type 1 diabetes and 9p21.3 with type 2 diabetes have both been replicated in other studies using independent data sets. Overall, localized haplotype cluster analysis had better success detecting disease associated variants than a previous single-marker analysis of imputed HapMap SNPs. We found that stringent application of quality score thresholds to genotype data substantially reduced false-positive results arising from genotype error. In addition, we demonstrate that it is possible to simultaneously phase 16,000 individuals genotyped on genome-wide data (450 K markers) using the Beagle software package. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Identifying Sites for Elk Restoration in Arkansas

Abstract: We used spatial data to identify potential areas for elk (Cervus elaphus) restoration in Arkansas. To assess habitat, we used locations of 239 elk groups collected from helicopter surveys in the Buffalo National River area of northwestern Arkansas, USA, from 1992 to 2002. We calculated the Mahalanobis distance (D²) statistic based on the relationship between those elk-group locations and a suite of 9 landscape variables to evaluate winter habitat in Arkansas. We tested model performance in the Buffalo National River area by comparing the D² values of pixels representing areas with and without elk pellets along 19 fixed-width transects surveyed in March 2002. Pixels with elk scat had lower D² values than pixels in which we found no pellets (logistic regression: Wald χ² = 24.37, P < 0.001), indicating that habitat characteristics were similar to those selected by the aerially surveyed elk. Our D² model indicated that the best elk habitat primarily occurred in northern and western Arkansas and was associated with areas of high landscape heterogeneity, heavy forest cover, gently sloping ridge tops and valleys, low human population density, and low road densities. To assess the potential for elk-human conflicts in Arkansas, we used the analytical hierarchy process to rank the importance of 8 criteria based on expert opinion from biologists involved in elk management. The biologists ranked availability of forage on public lands as having the strongest influence on the potential for elk-human conflict (33%), followed by human population growth rate (22%) and the amount of private land in row crops (18%). We then applied those rankings in a weighted linear summation to map the relative potential for elk-human conflict. Finally, we used white-tailed deer (Odocoileus virginianus) densities to identify areas where success of elk restoration may be hampered due to meningeal worm (Parelaphostrongylus tenuis) transmission. By combining results of the 3 spatial data layers (i.e., habitat model, elk-human conflict model, deer density), our model indicated that restoration sites located in west-central and north-central Arkansas were most favorable for reintroduction.     

Independent associations of TOMM40 and APOE variants with body mass index

The TOMM40‐APOE variants are known for their strong, antagonistic associations with Alzheimer's disease and body weight. While a stronger role of the APOE than TOMM40 variants in Alzheimer's disease was suggested, comparative contribution of the TOMM40‐APOE variants in the regulation of body weight remains elusive. We examined additive effects of rs2075650 and rs157580 TOMM40 variants and rs429358 and rs7412 APOE variants coding the ε2/ε3/ε4 polymorphism on body mass index (BMI) in age‐aggregated and age‐stratified cohort‐specific and cohort‐pooled analysis of 27,863 Caucasians aged 20–100 years from seven longitudinal studies. Minor alleles of rs2075650, rs429358, and rs7412 were individually associated with BMI (β = ?1.29, p = 3.97 × 10^?9; β = ?1.38, p = 2.78 × 10^?10; and β = 0.58, p = 3.04 × 10^?2, respectively). Conditional analysis with rs2075650 and rs429358 identified independent BMI‐lowering associations for minor alleles (β = ?0.63, p = 3.99 × 10^?2 and β = ?0.94, p = 2.17 × 10^?3, respectively). Polygenic mega‐analysis identified additive effects of the rs2075650 and rs429358 heterozygotes (β = ?1.68, p = 3.00 × 10^?9), and the strongest BMI‐lowering association for the rs2075650 heterozygous and rs429358 minor allele homozygous carriers (β = ?4.11, p = 2.78 × 10^?3). Conditional analysis with four polymorphisms identified independent BMI‐lowering (rs2075650, rs157580, and rs429358) and BMI‐increasing (rs7412) associations of heterozygous genotypes with BMI. Age‐stratified conditional analysis revealed well‐powered support for a differential and independent association of the rs429358 heterozygote with BMI in younger and older individuals, β = 0.58, 95% confidence interval (CI) = ?1.18, 2.35, p = 5.18 × 10^?1 for 3,068 individuals aged ≤30 years and β = ?4.28, CI = ?5.65, ?2.92, p = 7.71 × 10^?10 for 6,052 individuals aged >80 years. TOMM40 and APOE variants are independently and additively associated with BMI. The APOE ε4‐coding rs429358 polymorphism is associated with BMI in older individuals but not in younger individuals.