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PubMed2026

Identification of Novel Sources and Genetic Mapping for Bacterial Leaf Streak Resistance in a Geographically Diverse Panel of Wheat.

Bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa (Xtu), has recently emerged as a significant threat to wheat production in the Northern Great Plains region of the United States. Deploying resistant cultivars is an economical and practical method of controlling BLS. To identify novel sources of BLS resistance, we screened a set of 355 bread wheat landraces and cultivars representing global diversity for their response to BLS. A wide distribution of seedling responses against BLS was observed, with most genotypes displaying a moderately to highly susceptible response. Notably, we identified 5 resistant and 33 moderately resistant responses. A high-resolution genome-wide association study using 302,524 high-quality single-nucleotide polymorphisms (SNPs) identified 10 significant marker-trait associations (MTAs) on chromosomes 1A, 1D, 3B, 4A, and 5A corresponding to unique genomic regions associated with BLS resistance. Compared with previous studies, four of these genomic regions are likely novel. Of these, MTA 'scaffold15531_2782724' associated with q5A.1 was highly significant (-log10P = 9.39) and exhibited the highest SNP effect (0.35). An association on chromosome 3B validated a previously identified 3B quantitative trait locus (QTL) mapped at approximately 6 Mbp in the hard red spring wheat cultivar 'Boost', and the high-resolution mapping from our study further refined the interval for this QTL. Furthermore, the narrow haplotype blocks reported in this study could be valuable for fine mapping of important regions. The novel resistant sources, along with identified genomic loci and corresponding SNP markers from this study, would be helpful for wheat-breeding programs to enhance BLS resistance.[Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

BLS↗
PubMed2003

Molecular characterization and expression of porcine bone morphogenetic protein receptor-IB in the uterus of cyclic and pregnant gilts.

Previous gene mapping analyses revealed a quantitative trait locus for uterine capacity on chromosome 8. Comparison of porcine and human genetic maps suggests that the bone morphogenetic protein receptor IB (BMPR-IB) gene may be located near this region. The objectives of this study were to 1) clone the full coding region for BMPR-IB, 2) examine BMPR-IB gene expression by the endometrium and its cellular localization in cyclic and pregnant gilts, and 3) map the BMPR-IB gene. By iterative screening of an expressed sequence tag library, we obtained a 3559-base pair cDNA clone including the full coding region of BMPR-IB. Endometrial BMPR-IB mRNA expression of White composite gilts was determined by Northern blotting in Days 10, 13, and 15 cyclic and Days 10, 13, 15, 20, 30, and 40 pregnant gilts. In cyclic gilts, endometrial BMPR-IB mRNA expression was elevated on Days 13 and 15 (P < 0.01) compared with Day 10. Expression of BMPR-IB mRNA was localized in both luminal and glandular epithelium on Day 15. However, in pregnant gilts, BMPR-IB mRNA expression was not significantly different in the endometrium from Day 10 to Day 20, and it was significantly decreased on Days 30 and 40 (P = 0.011). The BMPR-IB gene was mapped to 108 cM on chromosome 8. These findings show that BMPR-IB mRNA expression is regulated differently in cyclic and pregnant gilts; this pattern of gene expression may be important for endometrial function during the luteal phase of the estrous cycle as compared with early pregnancy.

Amino Acid Sequence↗
PubMed2001

Interrelationships of porcine X and Y chromosomes with pituitary gonadotropins and testicular size.

Endocrine and testicular responses to unilateral castration on 1, 10, 56, or 112 days of age were characterized in 132 Chinese Meishan (MS) x White composite (WC) crossbred boars in which testicular size associates with a quantitative trait locus (QTL) on X chromosome. At 220 days of age, testicles of boars unilaterally castrated on Day 1 or 10 weighed more and had greater total daily sperm production (DSP) than one testicle of bilaterally intact boars (P < 0.05); compensation did not double these two responses. Boars with MS alleles at the X chromosome QTL had smaller testicles, darker colored parenchyma, and lower total DSP than boars with WC alleles (P < 0.05). The MS alleles engendered greater (P < 0.05) plasma FSH and LH during puberty than WC alleles. Plasma FSH increased (P < 0.05) within 48 h of unilateral castration on Days 1, 10, and 56. Subsequent increases occurred earlier during puberty (P < 0.05) after unilateral castration at younger ages than after unilateral castration at older ages. Pubertal increases in plasma FSH and LH were greater (P < 0.05) in boars with MS alleles than in those with WC alleles for the X chromosome QTL. Breed of Y chromosome had no effect on testicular traits, FSH, testosterone, or estrone. For LH, boars with an MS Y chromosome had greater (P < 0.01) plasma LH across all ages than boars with a WC Y chromosome. We conclude that a gene or groups of genes that reside on the porcine X chromosome regulate testicular development and pubertal gonadotropin concentrations.

Aging↗
PubMed1999

Genetic determinants of plasma ACE and renin activity in young normotensive twins.

OBJECTIVE: We investigated the determinants of plasma renin activity (PRA) and plasma levels of angiotensin-converting enzyme (pACE), including the effect of the D/I polymorphism of the angiotensin-converting enzyme (ACE) gene, in monozygotic (MZ) and dizygotic (DZ) twins. METHODS: Sixty-nine pairs of twins underwent measurements of blood pressure, pACE and ACE D/I genotyping. In addition, in 30 pairs ambulatory blood pressure (ABP) monitoring was carried out. To ascertain twin's zygosity, some highly discriminating variable number of tandem repeats micro- and mini-satellite systems were analysed by polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis and silver staining. The D/I polymorphism was assessed by PCR; pACE was measured in triplicate with a colorimetric assay, and PRA by a commercial kit. In DZ twins, identity by descent of the D/I alleles was examined by PCR amplification of a highly polymorphic simple sequence repeat at the human growth hormone gene. RESULTS: pACE levels were significantly (P < 0.01) higher in DD (9.27 +/- 2.60 IU/l, mean +/-SD) than in II (6.68 +/- 3.0), with DI having intermediate levels (7.93 +/- 2.7). No difference of PRA between different D/I genotypes was found. Twin data analysis showed a statistically significant heritability of pACE, but not of PRA. No differences between MZ and DZ twins in PRA, pACE and the relationship of the D/I genotype with pACE was found. Besides showing that the D/I genotype was the most important predictor of pACE, a multivariate analysis demonstrated that identity by descent of the D/I allele, as assessed by growth hormone (GH) genotyping, also significantly affected pACE. CONCLUSIONS: In this study of normotensive twins, pACE and not PRA showed significant heritability, the former being tightly associated with the D/I ACE gene polymorphism, and/or with a quantitative trait locus in linkage disequilibrium with it.

Adult↗
PubMed1999

Differential brain atrial natriuretic peptide expression co-segregates with occurrence of early stroke in the stroke-prone phenotype of the spontaneously hypertensive rat.

OBJECTIVE: To determine how the downregulation of atrial natriuretic peptide (ANP) gene expression, previously demonstrated to occur only in the brain of the stroke-prone spontaneously hypertensive rat (SHRsp), in contrast to the stroke-resistant SHR (SHRsr), co-segregates with stroke occurrence in SHRsp/SHRsr F2 descendants in order to study the 'protective' role towards stroke previously demonstrated in SHRsp for the quantitative trait locus STR2 that also carries the ANP gene. DESIGN AND METHODS: Eight male SHRsp, eight male SHRsr and 16 male SHRsp/SHRsr F2-intercross animals (progeny of brother/sister mated F1 hybrids from an original cross between F0 SHRsp and SHRsr) were selected for this study. All rats were exposed to a stroke-permissive Japanese-style diet starting at the age of 6 weeks. Half of the F2 animals had early strokes; the remainder had late strokes. Blood pressure was measured before sacrifice. Analysis of brain ANP expression using an RNase protection assay was performed in all animals. RESULTS: Downregulation of brain ANP in the stroke-prone phenotype was found to co-segregate with the occurrence of early strokes in the F2 rats independently of blood pressure levels. CONCLUSIONS: The observed lower expression of ANP in the brains of stroke-prone rats appears to be the result of an inhibitory effect by another gene or genes. It seems unlikely that this specific trait represents a primary protective mechanism.

Animals↗
PubMed2004

Differential effects of ethanol on gamma-aminobutyric acid-A receptor-mediated synaptic currents in congenic strains of inbred long and short-sleep mice.

BACKGROUND: Ethanol enhances gamma-aminobutyric acid (GABA)A receptor-mediated responses in the brain, and this enhancement is greater in a mouse line behaviorally more sensitive to ethanol (long sleep) than in a line (short sleep) behaviorally less ethanol sensitive (assayed by loss of righting; sleep time). Quantitative trait locus (QTL) analysis of inbred long sleep (ILS) and inbred short sleep (ISS) phenotypes revealed four chromosomal regions (Lore1, Lore2, Lore4, and Lore5) that together account for approximately 50% of ethanol-induced sleep-time variance. Congenic strains were generated, each of which is homozygous for one of four ISS Lore QTLs on the ILS background. These congenic mouse strains are ideally suited for asking which QTL regions might correlate with other phenotypes that differ between ILS and ISS mice. Here we used the congenics to investigate altered GABAA responses to ethanol. METHODS: Evoked GABAA receptor-mediated inhibitory postsynaptic currents (IPSCs) were measured by whole-cell voltage-clamp recording procedures in CA1 pyramidal neurons in hippocampal brain slices. RESULTS: GABAA IPSC responses in hippocampal brain slices from ILS mice were significantly enhanced by 80 mM ethanol, whereas those from ISS mice were not affected. ILS.Lore2 and ILS.Lore5 congenic strains were significantly enhanced by 80 mM ethanol, similar to the background (control) ILS mice. However, ethanol had no significant effect on GABAA responses in ILS.Lore1 and ILS.Lore4 congenic mice, similar to the ISS mice, thus reflecting the influence of ISS alleles on the ILS phenotype. CONCLUSIONS: Our results suggest that alleles located in the Lore1 and Lore4 QTL regions confer ethanol sensitivity of GABAA receptor-mediated IPSCs. Thus, for these QTLs, GABAA IPSCs may represent an endophenotype of sedative/hypnotic sensitivity to ethanol. Although the Lore2 and Lore5 QTL regions have a significant effect on sleep time, they do not play a significant role in the differential ethanol enhancement of GABAA IPSCs between ILS and ISS mice.

Animals↗
PubMed2003

Up-regulation of cyr61 in vascular smooth muscle cells of spontaneously hypertensive rats.

In the present study, we applied a fluorescent differential display method to mRNAs from aortae of spontaneously hypertensive rats (SHRs), stroke-prone spontaneously hypertensive rats (SPSHRs), and their parental strain, Wistar Kyoto rats (WKYRs), to identify the genes involved in the development of hypertension. Through this screen we came across a gene that is consistently up-regulated in hypertensive rats. Nucleotide sequence determination of the corresponding cDNA revealed that the gene is the rat orthologue of cyr61. Northern blot analysis showed that cyr61 expression increases in SHR and SPSHR before the onset of hypertension and is sustained thereafter at higher levels than in age-matched WKYRs. In situ hybridization analysis demonstrated that cyr61 is expressed strongly in smooth muscle cells (SMCs) in media of SHR and SPSHR but not WKYR aorta. Fluorescent in situ hybridization mapped the cyr61 gene to rat chromosome 1p12-13, which is located in close proximity to a recently defined quantitative trait locus including NHE3 Na(+)/H(+) exchanger. Overexpression of the cyr61 gene in stably transfected rat SMC line A7r5 caused rather inhibitory effects on the proliferation and DNA and protein synthesis. Our results thus demonstrate for the first time that cyr61 can also act as a growth inhibitor in SMC of genetically hypertensive rats. This may reveal a new route for investigation of the pathogenesis of hypertension.

Amino Acid Sequence↗
PubMed2025

simPIC:flexible simulation of paired-insertion counts for single-cell ATAC sequencing data.

Single-cell Assay for Transposase Accessible Chromatin (scATAC-seq) is increasingly used at population scale to study how genetic variation shapes chromatin accessibility across diverse cell types. This widespread adoption of the assay has created a need for computational methods that can handle complex biological and technical variation. Yet method development is limited by the lack of flexible simulation tools with known ground truth. Here, we present simPIC, a simulation framework for generating realistic single-cell ATAC-seq data across individuals and cell types. simPIC supports both population-scale and single-individual simulations, with the ability to model cell groups, batch effects, and genotype-dependent variation in accessibility. These features enable realistic benchmarking for tasks such as chromatin accessibility quantitative trait locus (caQTL) mapping. simPIC generates data that closely match real datasets and better captures inter-individual and experimental variation compared to existing tools.

simulation↗
PubMed2026

SwinePan for pig graph-based pangenome and multiomics data mining.

Pigs are one of the most important livestock species worldwide. Although multiple high-quality reference genomes exist, reliance on a single linear reference limits the detection of structural variants (SVs) and the characterization of population-specific genetic diversity. To address this limitation, we developed SwinePan, a comprehensive and integrated multiomics database for pigs built on a graph-based pangenome framework. SwinePan incorporates a variome derived from the graph-based pangenome, covering 2,598 individuals across 35 breeds, including 185,759 SVs, 117 million SNPs, and 6.8 million indels. The database also integrates transcriptomic data from liver, loin muscle, abdominal fat, and backfat, along with over 150,000 phenotypic records. The online toolkit deployed in SwinePan enables genome-wide association studies (GWAS), expression quantitative trait locus (eQTL) mapping, and colocalization, while interactive modules visualize population structure and multiomics associations, streamlining candidate gene and variant exploration. Additionally, two proof-of-concept analyses demonstrate how SwinePan pinpoints trait-associated loci and deciphers their potential regulatory mechanisms.

Journal Article↗
PubMed1997

Computational and biological analysis of 680 kb of DNA sequence from the human 5q31 cytokine gene cluster region.

With the human genome project advancing into what will be a 7- to 10-year DNA sequencing phase, we are presented with the challenge of developing strategies to convert genomic sequence data, as they become available, into biologically meaningful information. We have analyzed 680 kb of noncontiguous DNA sequence from a 1-Mb region of human chromosome 5q31, coupling computational analysis with gene expression studies of tissues isolated from humans as well as from mice containing human YAC transgenes. This genomic interval has been noted previously for containing the cytokine gene cluster and a quantitative trait locus associated with inflammatory diseases. Our analysis identified and verified expression of 16 new genes, as well as 7 previously known genes. Of the total of 23 genes in this region, 78% had similarity matches to sequences in protein databases and 83% had exact expressed sequence tag (EST) database matches. Comparative mapping studies of eight of the new human genes discovered in the 5q31 region revealed that all are located in the syntenic region of mouse chromosome 11q. Our analysis demonstrates an approach for examining human sequence as it is made available from large sequencing programs and has resulted in the discovery of several biomedically important genes, including a cyclin, a transcription factor that is homologous to an oncogene, a protein involved in DNA repair, and several new members of a family of transporter proteins.

Animals↗
PubMed2003

Large-scale identification and analysis of genome-wide single-nucleotide polymorphisms for mapping in Arabidopsis thaliana.

Genetic markers such as single nucleotide polymorphisms (SNPs) are essential tools for positional cloning, association, or quantitative trait locus mapping and the determination of genetic relationships between individuals. We identified and characterized a genome-wide set of SNP markers by generating 10,706 expressed sequence tags (ESTs) from cDNA libraries derived from 6 different accessions, and by analysis of 606 sequence tagged sites (STS) from up to 12 accessions of the model flowering plant Arabidopsis thaliana. The cDNA libraries for EST sequencing were made from individuals that were stressed by various means to enrich for transcripts from genes expressed under such conditions. SNPs discovered in these sequences may be useful markers for mapping genes involved in interactions with the biotic and abiotic environment. The STS loci are distributed randomly over the genome. By comparison with the Col-0 genome sequence, we identified a total of 8051 SNPs and 637 insertion/deletion polymorphisms (InDel). Analysis of STS-derived SNPs shows that most SNPs are rare, but that it is possible to identify intermediate frequency framework markers that can be used for genetic mapping in many different combinations of accessions. A substantial proportion of SNPs located in ORFs caused a change of the encoded amino acid. A comparison of the density of our SNP markers among accessions in both the EST and STS datasets, revealed that Cvi-0 is the most divergent accession from Col-0 among the 12 accessions studied. All of these markers are freely available via the internet.

Arabidopsis↗
PubMed2003

Functional divergence of a syntenic invertase gene family in tomato, potato, and Arabidopsis.

Comparative analysis of complex developmental pathways depends on our ability to resolve the function of members of gene families across taxonomic groups. LIN5, which belongs to a small gene family of apoplastic invertases in tomato (Lycopersicon esculentum), is a quantitative trait locus that modifies fruit sugar composition. We have compared the genomic organization and expression of this gene family in the two distantly related species: tomato and Arabidopsis. Invertase family members reside on segmental duplications in the near-colinear genomes of tomato and potato (Solanum tuberosum). These chromosomal segments are syntenically duplicated in the model plant Arabidopsis. On the basis of phylogenetic analysis of genes in the microsyntenic region, we conclude that these segmental duplications arose independently after the separation of the tomato/potato clade from Arabidopsis. Rapid regulatory divergence is characteristic of the invertase family. Interestingly, although the processes of gene duplication and specialization of expression occurred separately in the two species, synteny-based orthologs from both clades acquired similar organ-specific expression. This similar expression pattern of the genes is evidence of comparable evolutionary constraints (parallel evolution) rather than of functional orthology. The observation that functional orthology cannot be identified through analysis of expression similarity highlights the caution that needs to be exercised in extrapolating developmental networks from a model organism.

Arabidopsis↗
PubMed2000

SUT2, a putative sucrose sensor in sieve elements.

In leaves, sucrose uptake kinetics involve high- and low-affinity components. A family of low- and high-affinity sucrose transporters (SUT) was identified. SUT1 serves as a high-affinity transporter essential for phloem loading and long-distance transport in solanaceous species. SUT4 is a low-affinity transporter with an expression pattern overlapping that of SUT1. Both SUT1 and SUT4 localize to enucleate sieve elements of tomato. New sucrose transporter-like proteins, named SUT2, from tomato and Arabidopsis contain extended cytoplasmic domains, thus structurally resembling the yeast sugar sensors SNF3 and RGT2. Features common to these sensors are low codon bias, environment of the start codon, low expression, and lack of detectable transport activity. In contrast to LeSUT1, which is induced during the sink-to-source transition of leaves, SUT2 is more highly expressed in sink than in source leaves and is inducible by sucrose. LeSUT2 protein colocalizes with the low- and high-affinity sucrose transporters in sieve elements of tomato petioles, indicating that multiple SUT mRNAs or proteins travel from companion cells to enucleate sieve elements. The SUT2 gene maps on chromosome V of potato and is linked to a major quantitative trait locus for tuber starch content and yield. Thus, the putative sugar sensor identified colocalizes with two other sucrose transporters, differs from them in kinetic properties, and potentially regulates the relative activity of low- and high-affinity sucrose transport into sieve elements.

Amino Acid Sequence↗
PubMed1997

Quantitative trait loci associated with promoting effects of sodium L-ascorbate on two-stage bladder carcinogenesis in rats.

In the two-stage rat bladder carcinogenesis model using N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as an initiator and sodium L-ascorbate (SA) as a promoter, we found a notable strain difference between F344/DuCrj (F344) and WS/Shi (WS) rats in susceptibility to the promoting effect of SA. Twenty each of F344, WS and reciprocal F1 hybrid rats were given 0.05% BBN in their drinking water for 4 weeks and then a basal diet with (BBN-SA group) or without (BBN group) a 5% SA supplement for 32 weeks. In F344 and also in reciprocal F1 hybrids, the number of tumors per rat was significantly higher in the BBN-SA group than in the BBN group (P < 0.0001). In contrast, WS rats were not significantly affected by either treatment (P = 0.8). These findings indicate that F344 rats are highly susceptible to the promoter effect of SA, but WS rats are not. Linkage analysis of 108 WSx (WS x F344) F1 backcrosses revealed that this difference was related to a quantitative trait locus mapped on rat Chr. 17 (maximum LOD score, 3.86) named Bladder Tumor Susceptible-1 and possibly another locus on Chr. 5 (maximum LOD score, 2.39). This study has provided the first evidence that host genes influence the risk of bladder cancer development.

Animals↗
PubMed1995

Casein haplotypes and their association with milk production traits in the Finnish Ayrshire cattle.

Polymorphism of casein genes was studied in half-sib families of artificial insemination bulls of the Finnish Ayrshire dairy breed. Ten grandsires and 300 of their sons were genotyped for the following polymorphisms: alpha s1-casein (B, C), beta-casein (A1, A2), the microsatellite within the kappa-casein gene (ms5, ms4) and kappa-casein (A, B, E). Nine different combinations of these alleles, casein haplotypes, were found. Associations between casein haplotypes and milk production traits (milk and protein yield, fat and protein percentage and milking speed) were studied with ordinary least-squares analysis to find a direct effect of the haplotypes or an association within individual grandsire families using the granddaughter design. Estimated breeding values of sons were obtained from cow evaluation by animal model. No direct effect of the casein haplotypes on the traits was found. Within grandsire families, in one out of four families the chromosomal segment characterized by haplotype 3 (B-A2-ms4-A) was associated with an increase in milk yield (P < 0.01) and a decrease in fat percentage (P < 0.01) when contrasted with haplotype 8 (B-A1-ms4-E). The results provide evidence that in the Finnish Ayrshire breed at least one quantitative trait locus affecting the genetic variation in yields traits is segregating linked to either haplotype 3 (B-A2-ms4-A) or 8 (B-A1-ms4-E).

Animals↗
PubMed1997

Relationship of growth hormone and insulin-like growth factor-1 genotypes with growth and carcass traits in swine.

The contribution of chromosomal regions linked to growth hormone (GH) and insulin-like growth factor-1 (IGF-1) loci to variation in preweaning average daily gain, postweaning average daily gain (ADG), 10th rib backfat, loin-eye area and muscle pH were evaluated. Offspring of four purebred sires (A-D; n = 150, 195, 148 and 136, respectively) and two cross-bred sires (E and F; n = 157 and 145, respectively) were genotyped initially with GH and IGF-1 markers. When results of single marker analysis suggested possible linkage with a quantitative trait locus (QTL), additional flanking markers were typed for the family and interval mapping was performed. Growth hormone genotype was not associated with the traits evaluated in the study. Evidence suggestive of linkage was found for IGF-1 genotype and ADG in one sire family (lod = 2.3) where differences were 0.032 +/- 0.01 kg/day for alternative sire alleles. Evidence for a putative ADG QTL was greatest in the interval between IGF-1 and Sw1071. A similar genomic region has been associated with growth variation in mice; however, QTL mapping precision in the current study is insufficient to establish similarity.

Alleles↗
PubMed2006

A predicted microsatellite map of the passerine genome based on chicken-passerine sequence similarity.

Abstract We present a predicted passerine genome map consisting of 196 microsatellite markers distributed across 25 chromosomes. The map was constructed by assigning chromosomal locations based on the sequence similarity between 550 publicly available passerine microsatellites and the draft chicken genome sequence published by the International Chicken Genome Sequencing Consortium. We compared this passerine microsatellite map with a recently published great reed warbler (Acrocephalus arundinaceus) linkage map derived from the segregation of marker alleles in a pedigree of a natural population. Twenty-four microsatellite markers were shared between the two maps, distributed across ten chromosomes. Synteny was maintained between the predicted passerine microsatellite map and the great reed warbler linkage map, confirming the validity and accuracy of our approach. Possible applications of the predicted passerine microsatellite map include genome mapping; quantitative trait locus (QTL) discovery; understanding heterozygosity-fitness correlations; investigating avian karyotype evolution; understanding microsatellite mutation processes; and for identifying loci conserved in multiple species, unlinked loci for use in genotyping sets and sex-linked markers.

Animals↗
PubMed2004

Complex genetic architecture of population differences in adult lifespan of a beetle: nonadditive inheritance, gender differences, body size and a large maternal effect.

Evolutionary responses to selection can be complicated when there is substantial nonadditivity, which limits our ability to extrapolate from simple models of selection to population differentiation and speciation. Studies of Drosophila melanogaster indicate that lifespan and the rate of senescence are influenced by many genes that have environment- and sex-specific effects. These studies also demonstrate that interactions among alleles (dominance) and loci (epistasis) are common, with the degree of interaction differing between the sexes and among environments. However, little is known about the genetic architecture of lifespan or mortality rates for organisms other than D. melanogaster. We studied genetic architecture of differences in lifespan and shapes of mortality curves between two populations of the seed beetle, Callosobruchus maculatus (South India and Burkina Faso populations). These two populations differ in various traits (such as body size and adult lifespan) that have likely evolved via host-specific selection. We found that the genetic architecture of lifespan differences between populations differs substantially between males and females; there was a large maternal effect on male lifespan (but not on female lifespan), and substantial dominance of long-life alleles in females (but not males). The large maternal effect in males was genetically based (there was no significant cytoplasmic effect) likely due to population differences in maternal effects genes that influence lifespan of progeny. Rearing host did not affect the genetic architecture of lifespan, and there was no evidence that genes on the Y-chromosome influence the population differences in lifespan. Epistatic interactions among loci were detectable for the mortality rate of both males and females, but were detectable for lifespan only after controlling for body size variation among lines. The detection of epistasis, dominance, and sex-specific genetic effects on C. maculatus lifespan is consistent with results from line cross and quantitative trait locus studies of D. melanogaster.

Animals↗