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1.
Allozyme, microsatellite and mtDNA (RFLP and sequence) data of European red deer populations were examined as to their capability of indicating anthropogenic influences such as the keeping of animals in enclosures, selective hunting for trophies translocation of specimens to improve trophy quality and habitat fragmentation. Deer in enclosures revealed considerable deviations of allele frequencies from isolation-by-distance expectations but no remarkable loss of genetic diversity. Particular allozyme genotypes were associated with antler morphology, and selective hunting was shown to alter allele frequencies in the expected direction. Habitat fragmentation is reflected by various kinds of genetic markers but due to the lack of information on population histories no unequivocal evidence on particular human activities could be obtained.  相似文献   

2.
Heterozygosity-fitness correlations (HFCs) are increasingly reported but the underlying mechanisms causing HFCs are generally poorly understood. Here, we test for HFCs in roe deer ( Capreolus capreolus ) using 22 neutral microsatellites widely distributed in the genome and four microsatellites in genes that are potentially under selection. Juvenile survival was used as a proxy for individual fitness in a population that has been intensively studied for 30 years in northeastern France. For 222 juveniles, we computed two measures of genetic diversity: individual heterozygosity ( H ), and mean d 2 (relatedness of parental genomes). We found a relationship between genetic diversity and fitness both for the 22 neutral markers and two candidate genes: IGF1 (Insulin-like Growth Factor I) and NRAMP (natural resistance-associated macrophage protein). Statistical evidence and the size of genetic effects on juvenile survival were comparable to those reported for early development and cohort variation, suggesting a substantial influence of genetic components on fitness in this roe deer population. For the 22 neutral microsatellites, a correlation with fitness was revealed for mean d 2, but not for H , suggesting a possible outbreeding advantage. This heterosis effect could have been favored by introduction of genetically distant (Hungarian) roe deer to the population in recent times and, possibly, by the structuring of the population into distinct clans. The locus-specific correlations with fitness may be driven by growth rate advantages and resistance to diseases known to exist in the studied population. Our analyses of neutral and candidate gene markers both suggest that the observed HFCs are likely mainly due to linkage with dominant or overdominant loci that affect fitness ("local" effect) rather than to a genome-wide relationship with homozygosity due to inbreeding ("general" effect).  相似文献   

3.
J. Hojný 《Animal genetics》1973,4(3):161-168
The haemolytic reagent allowing direct serological detection of He homozygous pigs was obtained by the immunization of a Landrace sow. Another monospecific reagent prepared from immune serum of a Miniature pig made possible the evidence for a new factor of the H system - He. This factor is genetically controlled by the allele H be. Its frequency in Miniature pigs was 0.099.
The H system with alleles H 1=Ha, H2= Hb, H3= Hab, H4=Hcd, H5= Hbd, H6=Hbe and H7= H- continues to be a genetically open system.  相似文献   

4.
Allele frequency data from eight microsatellite loci provide evidence of highly significant genetic differentiation among stocks of Atlantic salmon Salmo salar L. from the Bay of Fundy, eastern and north-western Nova Scotia and Newfoundland. Estimates of genetic structure ( R ST and θ) were significant both among all samples taken from the different geographical locations and among samples from geographical regions for which more than one stock was sampled. Samples from the Bay of Fundy taken from stocks which are phenotypically and behaviourally diverse showed particularly high levels of genetic structure. Rogers', allele sharing and (δμ)2 distances also revealed significant differences among stock samples and were significantly correlated [Rogers' and (δμ)2] with sea distance between rivers. Results suggest that stocks of Atlantic salmon in eastern Canada are highly diverse genetically and that this should be an important consideration in any management programme for stocks in the area.  相似文献   

5.
The aim of the present study was to estimate the genetic, shared and nonshared environmental contributions to self-reported and parent-reported internalizing and externalizing problems in a follow-up study of intercountry adopted young adults. Young Adult Self-Report ratings were obtained from 1475 adoptees aged 22–32 years and Young Adult Behavior Checklist ratings from 1115 adoptive parents. For the genetic analyses, a subset of 143 adopted biologically related and 295 unrelated siblings was used. The data were subjected to model fitting decomposing three sources of variance: genetic factors (A) shared environment (C) and nonshared environment (E). Genetic factors were of more importance in both self-reported ( A 2= 54%, C 2= 0, and E 2= 46%) and parent-reported ( A 2= 76%, C 2= 15% and E 2= 9%) internalizing problems. Environmental factors were of more importance in both self-reported ( A 2= 33%, C 2= 17% and E 2= 50%) and parent-reported ( A 2= 28%, C 2= 27% and E 2= 45%) externalizing problems. This was in contrast with findings from the first and second assessments in the same sample during adolescence when genetic factors were more important in explaining externalizing problems compared with internalizing problems. Our results suggest a developmental reversal in genetic and environmental influences on behavior problems from early adolescence into adulthood, which could be related to different underlying developmental trajectories.  相似文献   

6.
So far, at least eight alleles in the goat CSN2 locus have been associated with the level of β -casein expression in milk. Alleles CSN2 A , CSN2 A 1, CSN2 B , CSN2 C , CSN2 D and CSN2 E have been associated with normal content (allele effects of about 5 g of β -casein per litre), whereas the CSN2 0 and CSN2 01 alleles have been associated with non-detectable levels of β -casein. Most of these alleles have been characterized genetically. Herein, we report the identification of a previously unreported SNP in the goat CSN2 promoter region ( AJ011018 :g.1311T>C), which is associated with the absence of β -casein in the milk. Furthermore, we developed a PCR-based method that allows detection of this mutation.  相似文献   

7.
Two new erythrocyte antigens have been detected by isoimmune antibodies obtained from Gottingen Miniature pigs. By family studies they proved to belong to the E system. The factor designated En is genetically controlled by alleles E 2= E edghkmn, E 3= E aegln, E 4= E edfhkmn, E 6= E aefln, E 9= E edghjmn, E 12= E aegmno and E edgkln, and the factor designated Eo by the allele E 12= E aegmno.
The En blood factor occurs in all the breeds studied and in frequency it comes close to a related Ee factor. It stands in opposition not only to Eb but also to Ei factor. The Eo factor can be characterized as a rarely occurring Ea subgroup. Besides being antithetic to Ed it is also antithetic to El and Ei factors. For the present, it was found only in Miniature pigs.  相似文献   

8.
In a programme aimed at tagging rust-resistance genes in flax with the maize transposable element Ac , a primary transformant of a line called 'Forge' that is homozygous for four rust-resistance genes, L 6, M, N and P 2, was identified that possessed 10 copies of the Ac element, one of which was linked (29 map units) to L 6. Descendants of this plant, which had from 8 to 15 copies of Ac , were crossed to a rust-susceptible line and the progeny screened for rust-susceptible mutants. When the Ac linked to L 6 was present in the parent, a high frequency of L 6 mutants was observed (29 mutants in 30 575). By contrast, when this Ac was absent, no such mutants were observed in 9258 progeny. The background frequency of L 6 mutants was low (five in 124 088). A detailed analysis was made of the first 11 L 6 mutants recovered from parents carrying the L 6-linked Ac element. While none of the mutants possessed a tagged resistance gene, all lacked an RFLP marker closely linked to L 6, suggesting that deletions were responsible for loss of the L 6 specificity. In many of the mutants, one or more RFLP markers in the vicinity of the linked Ac were also absent. These findings suggest that the linked Ac may be inducing chromosome breakage.  相似文献   

9.
Polymorphism for two autosomal alleles of equine plasminogen, PLG 1 and PLG 2, was demonstrated in plasma by isoelectric focusing and immunofixation, with a goat anti-human plasminogen antibody. The frequency of PLC 2 was 0.16 in 150 Standardbreds, 0.20 in 96 Thoroughbreds, and 0.39 in 32 Shetland ponies. No evidence for linkage of PLG with any of 13 marker loci was found.  相似文献   

10.
Effects of Rumpshaker Mutation on CNS Myelin Composition and Structure   总被引:1,自引:0,他引:1  
Abstract: Myelinated CNS tissues from homozygous/hemizygous and heterozygous jimpy rumpshaker jp rsh mutant mice were examined to determine the consequences on myelin structure of this mutation in the proteolipid protein (PLP) gene. Polyacrylamide gel electrophoresis and immunoblotting of brain homogenates confirmed that there was a decrease in PLP levels on the B6C3 genetic background onto which this gene was bred. We also observed an increase in level of a protein band that could correspond to the uncharacterized 10-kDa PLP previously reported in jp rsh mice on an Rb(1.3) 1Bnr background. High-performance TLC and densitometry of lipids from brain homogenate and isolated myelin revealed a decrease in content of cerebrosides and sulfatides. Electron microscopy on optic nerves revealed that normal radial component is retained in jp rsh myelin, further substantiating that PLP is not a component of this junctional complex. X-raydiffraction measurements on unfixed optic nerves showed that the jp rsh period is 5–10 Å larger than normal. Moreover, jp rsh optic nerve myelin was unstable, as evidenced by a continual increase in the period postdissection. jp rsh myelin that was equilibrated at varying pH and ionic strength typically had a larger than normal period under all conditions (both swelling and compacting). Our findings thus demonstrate that the biochemical abnormalities in the jp rsh mutant correlate with a wider periodicity and less stable packing of the myelin.  相似文献   

11.
RNA precursor uptake and incorporation, amino acid uptake and incorporation, and the characterization of newly synthesized RNA and protein in pools of normal morulae and pools containing one-third t 12/ t 12 morulae were compared. Maturing spermatoza of +/+ and T / t 12 animals were analyzed for RNA and protein content, and the RNA characterized. No differences in these parameters could be ascribed to the t 12 gene in homozygous embryos or haploid sperm.  相似文献   

12.
Summary
Sequence differences within the pig apoB gene can be used to identify rapidly four of eight known pig apoB alleles, designated LPB 1- LPB 8. We describe the use of gene amplification, followed by endonuclease digestion and agarose gel electrophoresis, to discern size and restriction site differences. LPB 5, a common allele associated with reduced low density lipoprotein clearance and hypercholesterolaemia in pigs, is identified by a 283-bp insertion in intron 28. LPB 3 and LPB 7 are distinguished by a unique Hind III site; LPB 8 shares a unique Hinc II site with LPB 5. This method facilitates identification of the apoB genotype of pigs used in lipoprotein research and allows for further investigation into the association of particular apoB alleles with lipoprotein metabolism abnormalities.  相似文献   

13.
Fine mapping of the FecL locus influencing prolificacy in Lacaune sheep   总被引:1,自引:0,他引:1  
In the Lacaune sheep population, two major loci influencing ovulation rate are segregating: FecX and FecL . The FecX L mutation is a non-conservative substitution (p.Cys53Tyr) in BMP15 that prevents the processing of the protein. Using a statistical approach, FecL has been shown to be an autosomal major gene. A full genome scan localized the FecL locus on sheep chromosome 11. Fine mapping reduced the interval containing FecL to markers BM17132 and FAM117A , corresponding to a synteny block of 1.1 megabases on human chromosome 17, which encompasses 20 genes. The expression of 16 genes from this interval was observed in tissues of the reproductive axis, but expression was not affected in homozygous FecL L females. In this interval, a unique haplotype was associated with the FecL L mutation. This particular haplotype could be predicted by the DLX3 :c.*803A>G SNP in the 3' UTR sequence of the DLX3 gene. This SNP provided accurate classification of animals (99.5%) as carriers or non-carriers of the mutation and therefore maybe useful in marker assisted selection. A synergistic action of FecL L and FecX L mutations on both ovulation rate and litter size was demonstrated. Until now, all the Fec genes identified in sheep belong to the bone morphogenetic protein (BMP) system. Based on the human orthologous region, none of the 20 genes in the FecL region corresponds to known molecules in the BMP system. The identification of the FecL L mutation could lead to the discovery of a new pathway involved in the regulation of ovulation rate.  相似文献   

14.
ABSTRACT. Rumen contents were obtained from 23 white-tailed deer (Odocoileus virginianus), located in the eastern portion of central Ohio. Samples were taken during late fall and winter over a 4-yr period, 1986–1990. Protozoan numbers ranged from 0.002 to 7.25 × 106 per ml of rumen contents, with a mean of 2.96 × 106. Six deer had protozoan concentrations higher than any values previously reported in ruminants. In all 23 animals, Entodinium dubardi was the only ciliate protozoan species present.  相似文献   

15.
Microsatellite measures of inbreeding: a meta-analysis   总被引:17,自引:0,他引:17  
Abstract Meta-analyses of published and unpublished correlations between phenotypic variation and two measures of genetic variation at microsatellite loci, multilocus heterozygosity (MLH) and mean d2, revealed that the strength of these associations are generally weak (mean r < 0.10). Effects on life-history trait variation were significantly greater than zero for both measures over all reported effect sizes ( r = 0. 0856 and 0.0479 for MLH and mean d 2, respectively), whereas effects on morphometric traits were not ( r = 0.0052 and r = 0.0038), which is consistent with the prediction that life-history traits exhibit greater inbreeding depression than morphometric traits. Effect sizes reported using mean d 2 were smaller and more variable than those reported using MLH, suggesting that MLH may be a better metric for capturing inbreeding depression most of the time. However, analyses of paired effect sizes reported using both measures from the same data did not differ significantly. Several lines of evidence suggest that published effects sizes are upwardly biased. First, effect sizes from published studies were significantly higher than those reported in unpublished studies. Second, fail-safe numbers for reported effect sizes were generally quite low, with the exception of correlations between MLH and life-history traits. Finally, the slope of the regression of effect size on sample size was negative for most sets of traits. Taken together, these results suggest that studies designed to detect inbreeding depression on a life-history trait using microsatellites will need to sample in excess of 600 individuals to detect an average effect size ( r = 0.10) with reasonable statistical power (0.80). Very few published studies have used samples sizes approaching this value.  相似文献   

16.
Lychnis alpina is a perennial caryophyllaceous plant with an amphi-Atlantic distribution. 27 populations are described on the basis of allozyme data from 11 electro-phoretic loci. L. alpina has a relatively low level of genetic variation, 3 of the loci are polymorphic ( P.,%= 20.2%) and the mean expected heterozygosity per indivindual is H3= 0.233 the three polymorphic loci included (H = 0.064, 11 loci included). Despite relatively low level of genetic variation, the genetic diversity among populations is relatively high with FST= 0.51. A hierarchial analysis of genetic diversity demonstrates that most of the genetic diversity exists as interpopulational, intra-regional diversity. Genetic identity is not associated with the intercontinental geographical distribution of the populations, neither is the diversity correspondant to taxonomic relationships.  相似文献   

17.
A genetic polymorphism of the pig amylase 2 system is described. It is controlled by two codominant genes, Am 2A and Am 2B. A comparison of some breeds from Byelorussian breeding farms gives the following frequencies for the alleles Am 2A and Am 2B , respectively: 0.35 and 0.865 in Large White (n = 682), 0.257 and 0.743 in Byelorussian Black and White (n = 400), 0.540 and 0.460 in Hampshire (n = 51).
While studying the genotype distribution according to the Hardy-Weinberg law, a genetic imbalance in Byelorussian Black and White pigs was established (χ2= 56.4). Genetic relationship between the Am 1 and Am 2 loci was not found.  相似文献   

18.
A method for genotyping K-casein ( A, B, E ), β-casein ( A 1, A 2, A 3, A5, B ) and β-lactoglobulin ( A, B ) simultaneously by the use of allele discrimination by primer length combined with automated detection of fragments with a sequencing instrument is described. Seven different mutations within the milk protein genes were analysed in order to distinguish between the alleles examined. The samples were amplified in two separate multiplex polymerase chain reactions (PCRs), which were then pooled and separated according to size in a single lane on the gel. By using stringent PCR conditions, we have been able to achieve allele-specific amplifications and minimize amplification of mismatched primer for all seven mutations.  相似文献   

19.
A total of 121 European fallow deer does, being either parous ( n = 15) or nulliparous ( n = 106), were treated with intravaginal progesterone impregnated controlled internal drug release (CIDR) devices for 14 days. The does were divided into three treatment groups and inseminated in utero by laparoscopy, at approximately 65 hours after CIDR device removal, with 25 × 106 fresh Mesopotamian ( n = 40), 25–35 × 106 frozen-thawed Mesopotamian ( n = 41) or 30–32.5 × 106 frozen-thawed European ( n = 40) fallow deer spermatozoa. The semen used had been collected, from two Mesopotamian and two European fallow deer bucks, by electroejaculation under general anaesthesia. Pregnancy was diagnosed by rectal ultrasonogrdphy on Day 50 after insemination.
There were no apparent differences in the quality of ejaculates between the two subspecies of fallow deer. The volume of semen and the total number of spermatozoa ranged between 0.6–1.2 ml and 2.11–4.95 × 109 per ml of semen, respectively. Evaluation of frozen-thawed spermatozoa revealed post-thaw motility rates between 50–70%. The overall conception rate was 65.3%. A higher conception rate was observed following insemination with European than Mesopotamian frozen-thawed spermatozoa (75% vs. 53.7%, respectively, P < 0.05). Insemination with fresh Mesopotamian spermatozoa increased the conception rate to a level not significantly different from that observed following insemination with European frozen-thawed spermatozoa (67.5% vs. 75%, for fresh Mesopotamian and frozen-thawed European semen, respectively).  相似文献   

20.
The effects of external K+, H+ and Ca2+ concentrations on the intracellular K+ concentration, [K+]i, and the K+-ATPase activity in 2-day-old mung bean roots [ Vigna mungo (L.) Hepper] were investigated. [K+]i, in mung bean roots was markedly decreased by external K+ or H+ stress and did not recover the initial value even after the stress was removed. This decrease in [K+]i, gradually disappeared with the addition of (Ca2+. Ca2+ may offset the harmful effects of ion stress. Ca2+ seems to have two effects on K+ transport; control of K+ permeability and activation of K+ uptake, although K+-ATPase activity was inhibited by Ca2+ concentrations higher than 10–4 M. We suggest that Ca2+ activates K+ uptake indirectly through the acidification of the cytoplasm.  相似文献   

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