Newfoundland Population Research Articles

Investigating genetic introgression from farmed red foxes into the wild population in Newfoundland, Canada

Fur-animal farms can affect the genetic constitution of wild conspecifics through escape and subsequent interbreeding. We studied this problem in red foxes (Vulpes vulpes) on the Canadian island of Newfoundland, where a large commercial fox farm (the only large farm on the island) has operated adjacent to the native wild red fox population for >30 years. To test for gene flow from these fur-farm foxes into the wild population, we compared mitochondrial DNA (mtDNA) sequences and nuclear microsatellite genotypes (21 loci) of 93 individuals from the fox farm to those of 79 modern wild foxes sampled from across the island. For reference, we also included 12 historical museum specimens of wild eastern Canadian red fox, all of which were sampled before the introduction of fur farming in the region. Many mtDNA haplotypes were shared among contemporary farmed and wild foxes and the historical eastern Canadian samples, as expected based on the eastern Canadian origin of fur-farming. However, only the fur farm additionally contained haplotypes originating from other parts of North America. More significantly, microsatellite markers, which reflect contemporary gene flow, indicated strong differentiation (F ST ≥ 0.14, P < 0.001) between fur-farm and wild foxes (including the historical samples) and little to no gene flow between them. Admixture and principle components analyses similarly supported clear separation of fur-farm and wild red foxes. Together, these findings indicate that the presence of a large red fox fur farm had little, if any, effect on the genetic constitution of the native wild population in Newfoundland. Tight biosecurity (lack of escapees) or failure of captive-reared foxes to establish in the presence of native wild foxes could explain these findings.

A common variant in CLDN14 causes precipitous, prelingual sensorineural hearing loss in multiple families due to founder effect

Genetic isolates provide unprecedented opportunities to identify pathogenic mutations and explore the full natural history of clinically heterogeneous phenotypes such as hearing loss. We noticed a unique audioprofile, characterized by prelingual and rapid deterioration of hearing thresholds at frequencies >0.5 kHz in several adults from unrelated families from the island population of Newfoundland. Targeted serial Sanger sequencing of probands for deafness alleles (n = 23) that we previously identified in this founder population was negative. Whole exome sequencing in four members of the largest family (R2010) identified a CLDN14 (DFNB29) variant [c.488C>T; p. (Ala163Val)], likely pathogenic, sensorineural hearing loss, autosomal recessive. Although not associated with deafness or disease, CLDN14 p.(Ala163Val) has been previously reported as a variant of uncertain significance (VUS). Targeted sequencing of 169 deafness probands identified one homozygote and one heterozygous carrier. Genealogical studies, cascade sequencing and haplotype analysis across four unrelated families showed all subjects with the unique audioprofile (n = 12) were also homozygous for p.(Ala163Val) and shared a 1.4 Mb DFNB29-associated haplotype on chromosome 21. Most significantly, sequencing 175 population controls revealed 1% of the population are heterozygous for CLDN14 p.(Ala163Val), consistent with a major founder effect in Newfoundland. The youngest CLDN14 [c.488C>T; p.(Ala163Val)] homozygote passed newborn screening and had normal hearing thresholds up to 3 years of age, which then deteriorated to a precipitous loss >1 kHz during the first decade. Our study suggests that genetic testing may be necessary to identify at-risk children in time to prevent speech, language and developmental delay.

Whole body-element composition of Atlantic salmon Salmo salar influenced by migration direction and life stage in three distinct populations.

Body-element content was measured for three life stages of wild Atlantic salmon Salmo salar from three distinct Newfoundland populations as individuals crossed between freshwater and marine ecosystems. Life stage explained most of the variation in observed body-element concentration whereas river of capture explained very little variation. Element composition of downstream migrating post-spawn adults (i.e. kelts) and juvenile smolts were similar and the composition of these two life stages strongly differed from adults migrating upstream to spawn. Low variation within life stages and across populations suggests that S. salar may exert rheostatic control of their body-element composition. Additionally, observed differences in trace element concentration between adults and other life stages were probably driven by the high carbon concentration in adults because abundant elements, such as carbon, can strongly influence the observed concentrations of less abundant elements. Thus, understanding variation among individuals in trace elements composition requires the measurement of more abundant elements. Changes in element concentration with ontogeny have important consequences the role of fishes in ecosystem nutrient cycling and should receive further attention.

High dietary choline and betaine intake is associated with low insulin resistance in the Newfoundland population

ObjectiveDietary betaine supplement could ameliorate insulin resistance (IR) in animals, but no data are available for choline. Reports on humans are rare. The aim of this study was to investigate the association between dietary choline and betaine intake and IR in humans. MethodsWe assessed 2394 adults from the CODING (Complex Diseases in the Newfoundland population: Environment and Genetics) study. Intake of dietary choline and betaine was evaluated from the Willett Food Frequency Questionnaire. IR was estimated by homeostatic model assessment (HOMA-IR) and the quantitative insulin-sensitivity check index (QUICKI). Partial correlation analysis was used to determine the correlations of dietary choline and betaine intake with IR adjusted for major confounding factors. ResultsDietary choline and betaine intake was inversely correlated with levels of fasting glucose and insulin, HOMA-IR, HOMA-β (r = −0.08 to −0.27 for choline and r = −0.06 to −0.16 for betaine; P < 0.05) and positively related to QUICKI (r = 0.16–0.25 for choline and r = 0.11–0.16 for betaine; P < 0.01) in both sexes after controlling for age, total calorie intake, and physical activity level. The significant associations disappeared in men after percent trunk fat was added as a confounding factor. Furthermore, individuals with the highest tertile of dietary choline and betaine intake had the lowest IR severity. Dietary choline and betaine intake, however, was the lowest in the high IR group, intermediate in the medium group, and the highest in the low IR group. ConclusionThis study demonstrated that higher intake of dietary choline and betaine is associated with lower IR in the general population.

Suicide Rates in Aboriginal Communities in Labrador, Canada.

To compare suicide rates in Aboriginal communities in Labrador, including Innu, Inuit, and Southern Inuit, with the general population of Newfoundland, Canada. In partnership with Aboriginal governments, we conducted a population-based study to understand patterns of suicide mortality in Labrador. We analyzed suicide mortality data from 1993 to 2009 from the Vital Statistics Death Database. We combined this with community-based methods, including consultations with Elders, youths, mental health and community workers, primary care clinicians, and government decision-makers. The suicide rate was higher in Labrador than in Newfoundland. This trend persisted across all age groups; however, the disparity was greatest among those aged 10 to 19 years. Males accounted for the majority of deaths, although suicide rates were elevated among females in the Inuit communities. When comparing Aboriginal subregions, the Innu and Inuit communities had the highest age-standardized mortality rates of, respectively, 165.6 and 114.0 suicides per 100 000 person-years. Suicide disproportionately affects Innu and Inuit populations in Labrador. Suicide rates were high among male youths and Inuit females.

Higher Dietary Choline and Betaine Intakes Are Associated with Better Body Composition in the Adult Population of Newfoundland, Canada.

BackgroundCholine is an essential nutrient and betaine is an osmolyte and methyl donor. Both are important to maintain health including adequate lipid metabolism. Supplementation of dietary choline and betaine increase muscle mass and reduce body fat in animals. However, little data is available regarding the role of dietary choline and betaine on body composition in humans.ObjectiveTo investigate the association between dietary choline and betaine intakes with body composition in a large population based cross-sectional study.DesignA total of 3214 subjects from the CODING (Complex Disease in Newfoundland population: Environment and Genetics) study were assessed. Dietary choline and betaine intakes were computed from the Willett Food Frequency questionnaire. Body composition was measured using dual-energy X-ray absorptiometry following a 12-hour fast. Major confounding factors including age, sex, total calorie intake and physical activity level were controlled in all analyses.ResultSignificantly inverse correlations were found between dietary choline and betaine intakes, with all obesity measurements: total percent body fat (%BF), percent trunk fat (%TF), percent android fat (%AF), percent gynoid fat (%GF) and anthropometrics: weight, body mass index, waist circumference, waist-to-hip ratio in both women and men (r range from -0.13 to -0.47 for choline and -0.09 to -0.26 for betaine, p<0.001 for all). Dietary choline intake had stronger association than betaine. Moreover, obese subjects had the lowest dietary choline and betaine intakes, with overweight subjects in the middle, and normal weight subjects consumed the highest dietary choline and betaine (p<0.001). Vice versa, when subjects were ranked according to dietary choline and betaine intakes, subjects with the highest intake of both had the lowest %TF, %AF, %GF, %BF and highest %LM among the groups in both sexes.ConclusionOur findings indicate that high dietary choline and betaine intakes are significantly associated with favorable body composition in humans.

Assessing the Causality Factors in the Association between (Abdominal) Obesity and Physical Activity among the Newfoundland Population-A Mendelian Randomization Analysis.

A total of 1,263 adults from Newfoundland and Labrador were studied in the research. Body mass index (BMI) and percent trunk fat (PTF) were analyzed as biomarkers for obesity. The Mendelian randomization (MR) approach with two single-nucleotide polymorphisms in the fat-mass and obesity (FTO) gene as instruments was employed to assess the causal effect. In both genders, increasing physical activity significantly reduced BMI and PTF when adjusted for age and the FTO gene. The effect of physical activity was stronger on PTF than BMI. Direct observational analyses showed significant increase in BMI/PTF when physical activity decreased. A similar association in MR analyses was not significant. The association between physical activity and BMI/PTF could be due to reversed causality or common confounding factors. Our study provides insights into the causal contributions of obesity to physical activity in adults. Health intervention strategies to increase physical activity among adults should include some other plans such as improving diet for reducing obesity.

Genetic structure of the Newfoundland and Labrador population: founder effects modulate variability.

The population of the province of Newfoundland and Labrador (NL) has been a resource for genetic studies because of its historical isolation and increased prevalence of several monogenic disorders. Controversy remains regarding the genetic substructure and the extent of genetic homogeneity, which have implications for disease gene mapping. Population substructure has been reported from other isolated populations such as Iceland, Finland and Sardinia. We undertook this study to further our understanding of the genetic architecture of the NL population. We enrolled 494 individuals randomly selected from NL. Genome-wide SNP data were analyzed together with that from 14 other populations including HapMap3, Ireland, Britain and Native American samples from the Human Genome Diversity Project. Using multidimensional scaling and admixture analysis, we observed that the genetic structure of the NL population resembles that of the British population but can be divided into three clusters that correspond to religious/ethnic origins: Protestant English, Roman Catholic Irish and North American aboriginals. We observed reduced heterozygosity and an increased inbreeding coefficient (mean=0.005), which corresponds to that expected in the offspring of third-cousin marriages. We also found that the NL population has a significantly higher number of runs of homozygosity (ROH) and longer lengths of ROH segments. These results are consistent with our understanding of the population history and indicate that the NL population may be ideal for identifying recessive variants for complex diseases that affect populations of European origin.

Transatlantic secondary contact in Atlantic Salmon, comparing microsatellites, a single nucleotide polymorphism array and restriction-site associated DNA sequencing for the resolution of complex spatial structure.

Identification of discrete and unique assemblages of individuals or populations is central to the management of exploited species. Advances in population genomics provide new opportunities for re-evaluating existing conservation units but comparisons among approaches remain rare. We compare the utility of RAD-seq, a single nucleotide polymorphism (SNP) array and a microsatellite panel to resolve spatial structuring under a scenario of possible trans-Atlantic secondary contact in a threatened Atlantic Salmon, Salmo salar, population in southern Newfoundland. Bayesian clustering indentified two large groups subdividing the existing conservation unit and multivariate analyses indicated significant similarity in spatial structuring among the three data sets. mtDNA alleles diagnostic for European ancestry displayed increased frequency in southeastern Newfoundland and were correlated with spatial structure in all marker types. Evidence consistent with introgression among these two groups was present in both SNP data sets but not the microsatellite data. Asymmetry in the degree of introgression was also apparent in SNP data sets with evidence of gene flow towards the east or European type. This work highlights the utility of RAD-seq based approaches for the resolution of complex spatial patterns, resolves a region of trans-Atlantic secondary contact in Atlantic Salmon in Newfoundland and demonstrates the utility of multiple marker comparisons in identifying dynamics of introgression.

Persistent Organic Pollutants (Pops) Contamination In The Gulf Of St Lawrence: A Critical Environmental Health Issue For The Population Of Newfoundland (Canada)

Introduction: The Great Lakes and the St Lawrence River are heavily polluted with many different kinds of Persistent Organic Pollutants (POPs) from industrial activities, agriculture and numerous landfills in the US and Canada. Many species native to the river and the estuary show evidence of POPs contamination, indicating that these chemicals have moved up the food chain to higher trophic levels. The local population inhabiting the coasts of the river and estuary in Quebec are known to have serious health consequences due to consumption of contaminated local seafoods. Since the Gulf of St Lawrence is the primary drainage for the river, it can be expected that the local marine species are also contaminated with POPs. We intended to examine the extent of contamination of marine species in the Gulf of St Lawrence and estimate the health risks to the population of the adjacent island of Newfoundland. Methods: Peer-reviewed journal articles were retrieved using Google Scholar, PubMed and Science Direct. We used 'Gulf of St. Lawrence' and 'Newfoundland' as the standard terms and added one of the pollutants (persistent organic pollutants, pesticides, organochlorine, organophosphate, dioxin, dichlorodiphenyltrichloroethane, polychlorinated biphenyls, and polybrominated diphenyl ethers in each search. Results: There were 418 journal articles that contained our search terms. However there was no publication of a population-based survey of the adverse health impacts of POPs in Newfoundland. Discussion: The total population of the island of Newfoundland is over half-a-million, the majority of which live along the coast and regularly consume inshore seafood as part of local customs. Despite scattered information on pollution of marine species of the Gulf of St. Lawrence, there is virtually no report of health risks due to consumption of contaminated seafood products from the Gulf. We suggest conducting an extensive survey of exposure assessment and health risk of the population.

Ontogenetic differences in Atlantic salmon phosphorus concentration and its implications for cross ecosystem fluxes

Nutrient transport across ecosystem boundaries by migratory animals can regulate trophic and biogeochemical dynamics of recipient ecosystems. The magnitude and direction of net nutrient flow between ecosystems is modulated by life history, abundance and biomass, individual behavior, and body element composition of migrating individuals. We tested common assumptions applied to nutrient transport models regarding homeostasis of species' body element composition across space and ontogenetic stage. We quantified whole body phosphorus (P) concentration of three life stages of wild Atlantic salmon (Salmo salar L.) from three distinct populations in Newfoundland, Canada, to evaluate the importance of river of origin and life stage as predictors of salmon %P. We found that life stage was a more important predictor of salmon %P than river of origin, and that %P of post‐spawn adults migrating downstream to the ocean (i.e., kelts) was more similar to %P of juveniles migrating downstream to the ocean (i.e., smolts) than it was to %P of adults migrating upstream to spawn. We then compared nutrient flux for the three rivers over a 20‐year period calculated with body composition values extracted from existing literature and our direct measurements to evaluate how assumptions regarding spatial and ontogenetic homogeneity in salmon %P influenced the observed P fluxes. We demonstrate that assuming equality of kelt %P and adult %P results in an overestimate of net nutrient flux to rivers by Atlantic salmon and the erroneous conclusion that Atlantic salmon populations are unconditional sources of nutrients to their natal watersheds. Instead, Newfoundland's salmon populations are conditional sinks of freshwater P, which is the opposite functional role of Pacific salmon. Our results highlight that a better understanding of intraspecific variation in body element composition of fishes is a prerequisite to determining their role in global biogeochemical cycling.

Dietary patterns and colorectal cancer: results from a Canadian population-based study

BackgroundThe relationship between major dietary patterns and colorectal cancer (CRC) in other populations largely remains consistent across studies. The objective of the present study is to assess if dietary patterns are associated with the risk of CRC in the population of Newfoundland and Labrador (NL).MethodsData from a population based case–control study in the province of NL were analyzed, including 506 CRC patients (306 men and 200 women) and 673 controls (400 men and 273 women), aged 20–74 years. Dietary habits were assessed by a 169-item food frequency questionnaire (FFQ). Logistic regression analyses were performed to investigate the association between dietary patterns and the CRC risk.ResultsThree major dietary patterns were derived using factor analysis, namely a Meat-diet pattern, a Plant-based diet pattern and a Sugary-diet pattern. In combination the three dietary patterns explained 74% of the total variance in food intake. Results suggest that the Meat-diet and the Sugary-diet increased the risk of CRC with corresponding odds ratios (ORs) of 1.84 (95% CI: 1.19-2.86) and 2.26 (95% CI: 1.39-3.66) for people in the highest intake quintile compared to those in the lowest. Whereas plant-based diet pattern decreases the risk of CRC with a corresponding OR of 0.55 (95% CI: 0.35-0.87). Even though odds ratios (ORs) were not always statistically significant, largely similar associations across three cancer sites were found: the proximal colon, the distal colon, and the rectum.ConclusionThe finding that Meat-diet/Sugary-diet patterns increased and Plant-based diet pattern decreased the risk of CRC would guide the promotion of healthy eating for primary prevention of CRC in this population.

Bald eagle (Haliaeetus leucocephalus) population increases in Placentia Bay, Newfoundland: evidence for habitat saturation?

Letto, K. R., Y. F. Wiersma, J. Brazil, and B. Rodrigues. 2015. Bald eagle (Haliaeetus leucocephalus) population increases in Placentia Bay, Newfoundland: evidence for habitat saturation? Avian Conservation and Ecology 10(1): 4.http://dx.doi.org/10.5751/ACE-00729-100104

Hormonal and dietary characteristics in obese human subjects with and without food addiction.

The concept of food addiction (FA) is a potentially important contributing factor to the development of obesity in the general population; however, little is known about the hormonal and dietary differences between obesity with and without FA. Therefore, the aim of our study was to explore potential biomarkers, including various hormones and neuropeptides, which regulate appetite and metabolism, and dietary components that could potentially differentiate obesity with and without FA. Of the 737 adults recruited from the general Newfoundland population, 58 food-addicted and non-food-addicted overweight/obese individuals (FAO, NFO) matched for age, sex, BMI and physical activity were selected. A total of 34 neuropeptides, gut hormones, pituitary polypeptide hormones and adipokines were measured in fasting serum. We found that the FAO group had lower levels of TSH, TNF-α and amylin, but higher levels of prolactin, as compared to NFO group. The total calorie intake (per kg body weight), the dietary intake of fat (per g/kg body weight, per BMI and per percentage of trunk fat) and the percent calorie intake from fat and carbohydrates (g/kg) was higher in the FAO group compared to the NFO group. The FAO subjects consumed more sugar, minerals (including sodium, potassium, calcium and selenium), fat and its components (such as saturated, monounsaturated and trans fat), omega 3 and 6, vitamin D and gamma-tocopherol compared to the NFO group. To our knowledge, this is the first study indicating possible differences in hormonal levels and micro-nutrient intakes between obese individuals classified with and without food addiction. The findings provide insights into the mechanisms by which FA could contribute to obesity.

Work that –s!: Drag queens, gender, identity, and traditional Newfoundland English

Making use of three data sets of Newfoundland English, this paper uncovers the linguistic and social motivations and strategies used by young speakers to reclaim and re‐shape a traditional, local, relic language feature (verbal –s attachment, as inI goes). While each group that we discuss (young females, drag queens, and a sample of the Newfoundland population) is differently situated with respect to the broader local culture (i.e. they each have their own social identities), similarities and parallels in the reclamation and use of verbal –s indicate important processes that occur in the enregisterment and reappropriation of a salient, traditional linguistic form. Results indicate that the local social and linguistic reconstruction of a speech feature can change a path of decline and prove fertile ground for creating a unique identity that moves toward the global while still motioning to the past of a community.

Mapping the distribution of a prey resource: neonate caribou in Newfoundland

The recently diminished caribou (Rangifer tarandus) population in insular Newfoundland, Canada, has been severely limited by predation on newborn calves. These neonates are patchily distributed on the landscape; therefore, to adequately understand predator-prey interactions, the temporal and geographic extent of the distribution of caribou calves must be identified so that current areas with calves can be differentiated from areas without calves. We used telemetry locations of 309 caribou calves and 100 adult females from 4 herds, 2008–2010, to estimate the spatiotemporal distribution of caribou calves during the time when they were most vulnerable to predation, to evaluate the predictability of the calf resource among years, and to assess the degree of aggregation during calving. Patterns of calf distribution were predictable in time and space from year to year, with an average distributional overlap of 68% between years. The dispersion of female caribou during calving varied among herds from highly aggregated (8% and 20% of herd range) to more dispersed (50–70% of herd range). Postcalving (up to 9 weeks) distributions also varied among herds; the 2 more-dispersed herds remained sedentary, whereas both highly aggregated herds migrated away from their calving grounds at the end of June. The most-aggregated herd remained so as it migrated from its calving ground, whereas the less-aggregated herd spread out and moved in a variety of predictable directions. Dispersion and movement patterns varied with forest cover; herds with less forest cover in their range were more aggregated and migratory than herds with more forest cover.

Melanin-concentrating hormone receptor 1 polymorphisms are associated with components of energy balance in the Complex Diseases in the Newfoundland Population: Environment and Genetics (CODING) study

The melanin-concentrating hormone receptor 1 (MCHR1) is a G protein-coupled receptor that regulates energy balance and body composition in animal models. Inconsistent effects of MCHR1 polymorphisms on energy homeostasis in humans may partly be attributable to environmental factors. We examined the effect of 4 single nucleotide polymorphisms (rs133073, rs133074, rs9611386, and rs882111) in the MCHR1 gene on body composition as well as energy-related lifestyle factors (diet and physical activity). We also examined the effect of gene-lifestyle interactions on body composition. A total of 1153 participants (248 men and 905 women) from the cross-sectional Complex Diseases in the Newfoundland Population: Environment and Genetics (CODING) study were genotyped by using probe-based chemistry validated assays. Diet and physical activity were estimated by using validated frequency questionnaires, and body composition was assessed by using dual-energy X-ray absorptiometry. Three polymorphisms (rs9611386, rs882111, and rs133073) were associated with differences in body-composition measurements (all P < 0.05). There was an interaction between rs9611386 and carbohydrate intake on total mass and waist circumference (both P ≤ 0.01). There was also an interaction between rs9611386 and body mass index categories (normal weight, overweight, and obese) on energy intakes (P = 0.02). A similar interaction was shown with rs882111 (P = 0.02). Interactions were also observed between each of these polymorphisms (rs9611386, rs882111, and rs133073) and physical activity score on body-composition measurements (all P < 0.05). These findings suggest that polymorphisms in the MCHR1 gene are associated with differences in body composition and interact with physiologic and energy-related lifestyle factors.

Sperm plasticity to seawater temperatures in Atlantic cod Gadus morhua is affected more by population origin than individual environmental exposure

Atlantic cod is a key species of the North Atlantic ecosystem whose distribution will likely be affected by climate change. Although general temperature effects on reproduction are known, there is a dearth of information on population and individual level life history and repro- ductive plasticity responses to temperature change. We tested the hypothesis that the sperm of Atlantic cod of different genetic backgrounds (southern versus more northerly Newfoundland and Labrador) and of different environmental histories (reared in indoor tanks and fed a forage diet versus reared in sea cages and fed pellets) have different average plastic responses to tempera- ture. Male reproductive performance was examined at 4 temperatures by measuring sperm swim- ming characteristics at 10 and 30 s after motility activation. Genetic origin had a larger effect on sperm swimming characteristics than past environmental history. Moreover, groups derived from the southern population exhibited a more pronounced positive mean reaction norm than the group derived from the Newfoundland and Labrador population. This represents an example of cogradient variation as genotypes accentuate the thermal phenotypic plasticity. Even though there were differences between the groups in sperm swimming characteristics, this is unlikely sufficient to affect successful reproduction at the temperatures tested unless under sperm compe- tition. Thus, sperm performance should not be a limiting factor for reproduction under predicted increases in sea surface temperatures.

H63D Genotying for Hemochromatosis: Helper or Hindrance?

H63D Genotying for Hemochromatosis: Helper or Hindrance?

Effect of FTO Gene and Physical Activity Interaction on Trunk Fat Percentage Among the Newfoundland Population.

OBJECTIVETo explore the effect of FTO gene and physical activity interaction on trunk fat percentage.DESIGN AND METHODSSubjects are 3,004 individuals from Newfoundland and Labrador whose trunk fat percentage and physical activity were recorded, and who were genotyped for 11 single-nucleotide polymorphisms (SNPs) in the FTO gene. Subjects were stratified by gender. Multiple tests and multiple regressions were used to analyze the effects of physical activity, variants of FTO, age, and their interactions on trunk fat percentage. Dietary information and other environmental factors were not considered.RESULTSHigher levels of physical activity tend to reduce trunk fat percentage in all individuals. Furthermore, in males, rs9939609 and rs1421085 were significant (α = 0.05) in explaining central body fat, but no SNPs were significant in females. For highly active males, trunk fat percentage varied significantly between variants of rs9939609 and rs1421085, but there is no significant effect among individuals with low activity. The other SNPs examined were not significant in explaining trunk fat percentage.CONCLUSIONSHomozygous male carriers of non-obesity risk alleles at rs9939609 and rs1421085 will have significant reduction in central body fat from physical activity in contrast to homozygous males of the obesity-risk alleles. The additive effect of these SNPs is found in males with high physical activity only.