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1.
基于F-2群体的藏鸡羽色、胫色性状的遗传分析   总被引:4,自引:0,他引:4  
王存芳  李宁  吴常信 《遗传》2006,28(7):810-814
采用白来航、寿光鸡分别与藏鸡进行正反交交配,F1代进行自群交配产生F2群体,观察F1和F2代中羽色、胫色的表现和分离比例。结果表明,白来航鸡的白羽和寿光鸡的黑羽对藏鸡麻羽的遗传方式是完全显性遗传;麻羽是由两个或两个以上的等位基因决定的,只有同时存在这两个或两个以上的等位基因,才可能表现出麻羽来;决定胫色性状的Id/id基因为伴性遗传,隐性基因id在纯合子时有个逐步表达的过程;本研究证实了所用白来航公鸡胫色性状的基因型为显性纯合子。  相似文献   

2.
Based on the ecological features of the mole vole, family analysis of the inheritance of coat color was performed with the use of material collected in a wild population. Analysis of coat color in parents and offspring has demonstrated that the offspring segregation into black and nonblack animals after crosses of different types agrees with the hypothesis on the monogenic inheritance of these color variations. Black mole voles are homozygous for the recessive allele (genotype aa). Homozygotes for the dominant allele (AA) are brown. Heterozygotes (Aa) may be brown or have transitional color. The mean frequency of brown coat color in heterozygotes is 0.509 and is very variable. The higher the color intensity in black elements of parent coat color, the more is the offspring coat color saturated with these elements.  相似文献   

3.
The harlequin color pattern of Great Dane dogs differs from merle in that the background is white instead of blue. Harlequin by harlequin matings produced 60 black, 77 harlequin, 42 merle, and 35 homozygous merle pups. Harlequin by black matings produced 44 black, 26 harlequin, 25 merle, and one white (homozygous merle?) pups. All harlequins produced some merles. These data best fit the hypothesis that harlequin is a modification of merle (Mm) caused by an autosomal dominant mutation that is lethal to homozygotes, and to about half of heterozygotes when combined with the MM genotype. The symbol H is proposed for this mutation.  相似文献   

4.
The growth, physiology and skin pigmentation of pacamã Lophiosilurus alexandri juveniles were evaluated in an experiment using different tank colours (white, yellow, green, blue, brown and black) over an 80 day period. The tank colours did not cause significant differences to final body mass, total length, survival rate, carcass composition (moisture, crude protein, ash, ether extract, calcium, phosphorus, energy), or to plasma protein, triglyceride and cholesterol values. Haematocrit values, however, were highest for fish kept in white tanks (ANOVA P < 0·05), while the greatest haemoglobin levels were recorded for fish kept in blue and brown tanks (P < 0·01). The concentrations of cortisol (P < 0·001) and glucose (P < 0·01) were the most in fish in the black tanks. Tank colour affected skin pigmentation significantly, with fish in white tanks having the highest values of L* (brightness) and the lowest values in blue and black tanks. L*, however, decreased in all treatments throughout the experiment. C*ab increased significantly over the course of the experiment in fish kept in white tanks. Similar increases of C*ab were recorded in the other treatments but to a lesser extent. The use of black tanks during the cultivation of L. alexandri caused stress and should be avoided. Cultivation in white and yellow tanks produced individuals with a pale skin colour, while cultivation in blue and black tanks resulted in juveniles with a darker and more pigmented skin.  相似文献   

5.
Two single nucleotide polymorphisms rs12979860C/T and rs8099917T/G around interleukin-28B (IL28B) locus have been extensively investigated in their association with hepatitis C virus (HCV) spontaneous clearance. However, with the variable and even inconsistent results, it is necessary to conduct a meta-analysis. A literature search was conducted to seek articles about genetic variation of IL28B and spontaneous clearance of HCV. Odds ratio with 95% confidential interval were calculated to estimate their relationship. Furthermore, meta-regression analysis was performed to search for potential affective factors. A total of 8 studies including 2460 patients with chronic HCV infection and 1052 individuals with spontaneous HCV clearance met inclusion criteria, in which seven studies describing rs12979860 and three studies describing rs8099917. Analysis performed in Caucasian populations indicated that rs12979860CC and rs8099917TT contributed to HCV spontaneous clearance in both dominant model (CC vs. CT + TT, P < 1 × 10− 4; TT vs. TG + GG, P < 10− 4, respectively) and co-dominant model (CC vs. CT, P < 1 × 10− 4, CC vs. TT, P < 1 × 10− 4; TT vs. TG, P < 10− 4, TT vs. GG, P = 0.012, respectively). Meta-regression analysis suggested that male proportion (P = 1 × 10− 5) and mean age (P = 1 × 10− 3) might weaken the effect of rs12979860CC, but HCV genotype 1/4 (P = 4 × 10− 4) might contribute to it. IL28B rs12979860CC and rs8099917TT genotypes contribute to spontaneous HCV clearance in Caucasians.  相似文献   

6.
In this paper, the incorporation of methamphetamine (MA) into rat hair was studied. The main purpose of this study was to investigate whether MA can be detected or positive hair results can be obtained in hair of rats administered a single dose of MA. The relationship between dose and frequency of administration and the concentrations of MA and its metabolite, amphetamine (AP), in rat hair were evaluated and the MA and AP concentrations in white and pigmented hair were compared. MA was administered to rats as follows: low dose (0.5 mg/kg/day), medium dose (2 mg/kg/day) and high dose (10 mg/kg/day). The frequency of administration was one time per day for 1, 2, 3, 4, 5, 15 and 30 days. Hair and urine samples were collected from rats and analyzed by gas chromatography/mass spectrometry (GC/MS). MA could be identified in pigmented rat hair when MA was administered for 4 or more days at low daily dose and on day 1 following administration of medium and high daily doses. Positive results for MA were obtained from pigmented rat hair when MA was administered for 30 days at low daily dose, for 4 or more days at medium daily dose, or for 2 or more days at high daily dose. The concentrations of MA and AP found in rat hair were proportional to the dose and frequency of administration. The concentrations of MA and AP in pigmented rat hair were 2–10 times higher than those in white rat hair. The results of this study on the incorporation of MA into rat hair can serve as a model to better understand the incorporation of MA into human hair even though there are differences between animal models and human hair.  相似文献   

7.
Freshwater inflows from river diversions may affect nekton populations by altering the salinity and temperature of estuarine waters. To investigate the influence of these environmental variables on the growth and survival rates of brown shrimp Farfantepenaeus aztecus and white shrimp Litopenaeus setiferus, we conducted field experiments in May and September 2007 to expose experimental animals to the range of different combinations of salinity and water temperature that commonly occur in an estuarine environment. Growth rates for shrimp held in mesocosms for approximately 7 days were compared among four locations and three treatments; locations were identified by the dominant marsh vegetation and distance from the Gulf of Mexico (low to high salinity: Intermediate, Brackish, Saline UE = Saline Up Estuary, Saline DE = Saline Down Estuary). At each location, the treatments were replicated four times and included shallow water with additional food, shallow water without food added, and deeper water (an attempt to expose animals to lower temperatures). Our experiments were designed to test the null hypothesis that shrimp growth and survival rates did not differ by location or treatment. Both brown shrimp and white shrimp grew more slowly at the Intermediate than higher salinity locations. Potential prey (benthic infauna) biomass was relatively low at both the Intermediate and Brackish locations in May, and both shrimp species consistently grew faster in mesocosms where food was added. We conclude that reduced growth in low salinity environments is likely due to the combined effects of increased metabolic costs and less food in these areas. River diversions that reduce estuarine salinities over a large portion of available habitat during peak recruitment periods may reduce overall growth rates and shrimp productivity in the affected areas.  相似文献   

8.
The purple pericarp color in rice was controlled by two dominant complementary genes, Pb and Pp. Crossing black rice ‘Heugnambyeo’ variants with three varieties of white pericarp rice gave a segregation ratio of 9 purple: 3 brown: 4 white. The Pp genes were segregated by homozygous PpPp alleles for the dark purple pericarps, heterozygous Pppp alleles for the medium and mixed purple pericarps, and homozygous pppp alleles for either brown or white pericarps with a 1 PpPp: 2 Pppp: 1 pppp segregation ratio, indicating that the Pp allele in rice is incompletely dominant to the recessive pp allele. Among the purple seeds, the amount of cyanidin-3-O-glucoside was higher in the dark purple seeds (Pb_PpPp) than in the medium purple seeds (Pb_Pppp). Moreover, no cyanidin-3-glucoside was detected in brown (Pb_pppp) or white pericarp seeds (pbpbpppp). These findings indicated that the level of cyanidin-3-glucoside was determined by the copy number of the Pp allele. Further genotype investigation of the F3 progeny demonstrated that the dominant Pb allele was present in either purple or brown pericarp. A 2-bp (GT) deletion from the DNA sequences of the dominant and functional Pb was found in the same DNA sequences of the recessive and non-functional pb allele. These findings suggested that the presence of at least a dominant Pb allele was an essential factor for color development in rice pericarps. In conclusion, the Pp allele in rice is incompletely dominant to the recessive pp allele; thus, the number of dominant Pp alleles determines the concentration of cyanidin-3-O-glucoside in black rice.  相似文献   

9.
M. L. Ryder    R. B. Land    R. Ditchburn 《Journal of Zoology》1974,173(4):477-485
Analysis of the numerical proportions of Soay, Orkney and Shetland sheep of different colours together with test matings, produced results compatible with the hypothesis that these breeds have a multiple allelic series at locus A , white ( A 1) being dominant to grey ( A 2) and both being dominant to the gene for self-colour ( A 5). The alleles at the A locus are epistatic to the alleles for pigment production at locus B , black ( B 1) being dominant to brown ( B 2).  相似文献   

10.
The relationships between testosterone concentrations in male African rhinoceros and the presence of conspecific males and females were investigated. Serum testosterone concentrations were measured using enzyme-linked immunoassay (EIA) in 37 male black rhinoceros (Diceros bicornis) and 21 male white rhinoceros (Ceratotherium simum) housed at 37 institutions in the USA. Testosterone concentrations in both black (n = 37) and white (n = 21) rhinoceros males rose with increasing numbers of females present (P < 0.05). Average testosterone concentrations also rose with an increased number of conspecific males (n = 34) in black rhinoceros (P < 0.05). However, no specific pattern was found among male white rhinoceros housed with other males. We inferred that introduction of females to a male may play an important role in stimulating libido and spermatogenesis. The similar response of black rhinoceros and white rhinoceros to increased numbers of females suggested that, at least historically, herd structure for blacks may have been more similar to whites than previously realized, and should be investigated further.  相似文献   

11.
Although some external coloration and pigmentation patterns in molluscan shells may be attributable to environmental factors, most variation in these phenotypic characters depends on uncomplicated genetic mechanisms. Genetic research on inheritance of color variations in the north-Chilean scallop (Argopecten purpuratus) has now been expanded to analyze color segregation in juvenile scallops produced under controlled conditions employing self- and cross-fertilization. Calculations from the results were used for comparison with different numerical models based on Mendelian inheritance, and results were also obtained on the inheritance of a dorsoventral white line often observed on the left (upper) valve in this species. The results confirmed the hereditary basis for color variation in the shell of this scallop, suggesting a simple, dominant model of epistasis to explain the distribution of the different color variants observed (purple, brown, orange, yellow, and white). The presence of the white line may be controlled by a recessive allele with simple Mendelian traits on a locus distinct from those that control color variation.  相似文献   

12.
Adults of the cabbage beetle Colaphellus bowringi display a summer diapause in response to the exposure of their larvae to long photoperiods. In the present study, the inheritance of the photoperiodic response controlling summer diapause in C. bowringi by crossing a high diapause strain (D strain) with a laboratory selected nondiapause strain (N strain) was investigated under different photoperiods at 22, 25 and 28 °C. The beetles in both reciprocal crosses and backcrosses showed a clear short-day response for the induction of diapause at all temperatures, similar to that of the D strain, suggesting that photoperiodic response of this beetle is heritable. The diapause incidences in the progeny from all the crosses under LD 15:9 or LD 12:12 at 25 °C suggest that genetic and genetic-environmental interactions are involved in diapause induction. The incidence of diapauses in F1 progeny was significantly lower than that in the D × D strain but significantly higher than that in the N × N strain, indicating that the diapause capability is inherited in an incomplete dominant manner. The incidence of diapause was greater among the offspring of hybrid females when those females had a D strain mother or grandmother rather than a N strain mother or grandmother, indicating that maternal effects on diapause induction are stronger than paternal effects. The laboratory selected nondiapause strain also showed a short-day photoperiodic response at a low temperature of 22 °C, indicating that the photoperiodic photoreceptor and photoperiodic clock still function in the nondiapause strain.  相似文献   

13.

Background

Evidence showed that the SCN1A IVS5N+5G>A polymorphism might be associated with susceptibility to epilepsy with febrile seizures (EFS), however, the published data were inconclusive. Therefore, a meta-analysis was performed to estimate the overall EFS risk with the polymorphism.

Methods

The PubMed and Medline were searched up to March, 2013 for studies on the association between SCN1A IVS5N+5G>A polymorphism and EFS risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by means of a genetic model free approach. The heterogeneity and sensitivity of each report and the publication bias were also performed. All the statistical analyses were done using the STATA 11.0 software.

Result

A total of 6 studies with 2719 cases and 2317 controls met the selection criteria. We found significant association between SCN1A polymorphism and EFS (A vs. G: OR = 1.498, 95%CI = 1.138–1.972; AA vs. GG: OR = 2.292, 95%CI = 1.620–3.243; AG vs. GG: OR = 1.414, 95%CI = 1.010–1.978; recessive model: OR = 1.747, 95%CI = 1.119–2.728 and dominant model: OR = 1.730, 95%CI = 1.259–2.376). When compared with the epilepsy without febrile seizure (EWFS), the subgroup analysis stratified by ethnicity showed that the SNP was significantly associated with EFS in Caucasian (A vs. G: OR = 1.505, 95%CI = 1.218–1.861; AA vs. GG: OR = 2.081, 95%CI = 1.358–3.189; recessive model: OR = 1.715, 95%CI = 1.273–2.310 and dominant model: OR = 1.625, 95%CI = 1.096–2.410), but not in Indian and Chinese. When applying Bonferroni correction (significance was set at 0.05/20), the Caucasian still has robust association with EFS and epilepsy.

Conclusion

The present meta-analysis suggests that SCN1A IVS5N+5G>A polymorphism is a risk factor of EFS and epilepsy, especially in Caucasian.  相似文献   

14.
Inheritance of extreme overweight in black families   总被引:2,自引:0,他引:2  
We used complex segregation analysis to compare the genetic transmission of overweight in randomly selected black (N = 60) and white (N = 961) families. In both groups we found evidence for polygenic transmission. Major gene inheritance was strongly supported in whites and was marginally supported in blacks. Parameter estimates for black and white families were similar, suggesting that overweight is similarly transmitted in the black and white families we observed. There was evidence in both black and white families for high gene frequency and recessive gene expression. Extreme phenotypes common in black families may be the result of interactions between major genotype and polygenic or environmental factors; alternative explanations for differences in black and white families' transmission patterns are discussed. Replication with a larger group of black families is needed to confirm our findings.  相似文献   

15.
We investigated whether diapause pupae of Byasa alcinous exhibit pupal color diphenism (or polyphenism) similar to the diapause pupal color polyphenism shown by Papilio xuthus. All diapause pupae of B. alcinous observed in the field during winter showed pupal coloration of a dark-brown type. When larvae were reared and allowed to reach pupation under short-day conditions at 18 °C under a 60 ± 5% relative humidity, diapause pupae exhibited pupal color types of brown (33%), light-brown (25%), yellowish-brown (21%), diapause light-yellow (14%) and diapause yellow (7%). When mature larvae reared at 18 °C were transferred and allowed to reach pupation at 10 °C and 25 °C under a 60 ± 5% relative humidity after a gut purge, the developmental ratio of brown and light-brown, yellowish-brown, and diapause light-yellow and diapause yellow types was 91.2, 8.8 and 0.0% at 10 °C, and 12.2, 48.8 and 39.0% at 25 °C, respectively. On the other hand, when mature larvae reared at 18 °C were transferred and allowed to reach pupation at 10 °C, 18 °C and 25 °C under an over 90% relative humidity after a gut purge, the developmental ratio of brown and light-brown, yellowish-brown, and diapause light-yellow and diapause yellow types was 79.8, 16.9 and 3.3% at 10 °C, 14.5, 26.9 and 58.6% at 18 °C, and 8.3, 21.2 and 70.5% at 25 °C, respectively. These results indicate that diapause pupae of brown types are induced by lower temperature and humidity conditions, whereas yellow types are induced by higher temperature and humidity conditions. The findings of this study show that diapause pupae of B. alcinous exhibit pupal color diphenism comprising brown and diapause yellow types, and suggest that temperature and humidity experienced after a gut purge are the main factors that affect the diapause pupal coloration of B. alcinous as environmental cues.  相似文献   

16.

Aims

Post-procedural myocardial necrosis manifested by elevated cardiac troponin T (cTnT) often complicates percutaneous coronary intervention (PCI). Plasma pentraxin 3 (PTX3) levels are increased in patients with arterial inflammation and especially unstable angina pectoris (UAP). This study tested whether plasma PTX3 levels can predict post-PCI cTnT elevation.

Main methods

We evaluated 94 consecutive patients with AP and normal pre-PCI cTnT levels who underwent PCI. Pre-PCI virtual histology-intravascular ultrasound was performed to assess culprit plaque composition. Plasma PTX3 and serum hs-CRP levels were measured pre-PCI. Patients were divided into 2 groups according to presence (Group I, n = 34) or absence (Group II, n = 60) of post-PCI cTnT elevation > 3 × the upper limit of normal at 24 h after PCI.

Key findings

Plasma PTX3 (4.06 ± 2.05 ng/ml vs 2.17 ± 1.02 ng/ml, p < 0.001), serum hs-CRP levels (0.25 ± 0.03 vs 0.16 ± 0.03 mg/dl, p = 0.048), plaque burden (80.9 ± 5.3 vs 75.4 ± 10.6%, p = 0.047), presence of positive remodeling (59 vs 25%, p = 0.034), and percent necrotic core area (19.0 ± 7.4 vs 14.0 ± 5.9%, p = 0.046) were significantly higher in Group I than in Group II. Receiver-operating characteristic curve analysis showed that with a best cut-off value of 2.83 ng/ml, plasma PTX3 level (AUC 0.823) predicted post-PCI cardiac TnT elevation better than did serum hs-CRP level (AUC 0.618). Multiple logistic regression analysis showed that plasma PTX3 level was the most independent predictor of post-PCI cardiac cTnT elevation (OR: 2.65; 95% CI: 1.56–10.1; p = 0.003).

Significance

Plasma PTX3 level may be a useful marker for predicting post-PCI cardiac cTnT elevation, which is associated with inflammatory status of culprit lesions.  相似文献   

17.
Cheprakov MI  Evdokimov NG  Glotov NV 《Genetika》2005,41(11):1552-1558
Based on the ecological features of the mole vole, family analysis of the inheritance of coat color was performed with the use of material collected in a wild population. Analysis of coat color in parents and offspring has demonstrated that the offspring segregation into black and nonblack animals after crosses of different types agrees with the hypothesis on the monogenic inheritance of these color variations. Black mole voles are homozygous for the recessive allele (genotype aa). Homozygotes for the dominant allele (AA) are brown. Heterozygotes (Aa) may be brown or have transitional color. The mean frequency of brown coat color in heterozygotes is 0.509 and is very variable. The higher the color intensity in black elements of parent coat color, the more is the offspring coat color saturated with these elements.  相似文献   

18.
A barley straw was modified by a surfactant, cetylpyridinium chloride, and used as an adsorbent for acid (acid blue 40) and reactive dye (reactive black 5) adsorption in aqueous solution. Characterization of the modified barley straw was performed using N2 adsorption, titration, and FT-IR analysis. It was found that the surfactant modified barley straw exhibits higher adsorption to acid blue 40 than reactive black 5 and adsorption of the dyes is influenced by several parameters such as dye initial concentration, adsorbent dosage, solution pH, and adsorption temperature. Adsorption isotherms show that maximum adsorption of acid blue 40 and reactive black 5 is 1.02 × 10−4 and 2.54 × 10−5 mol/g, respectively. Desorption studies show that both dyes are strongly bounded with the adsorbent and exhibit low desorption.  相似文献   

19.
N. K. Sen  M. K. Jana 《Genetica》1964,34(1):46-57
In black gram, the mode of inheritance of six pairs of characters has been analysed, viz.: erect versus spreading habit; hairy versus glabrous fruit; bluish black versus straw fruit colour; shiny versus dull seed surface; green versus brown seed colour. On the basis of the results, the following gene symbols are proposed:Erect habitSp is incompletely dominant over spreading,sp.—Hairy fruitG is dominant over glabrous,g, while inG plants the extent of hairiness is controlled by more than one pair of genes.—Bluish black fruit colourS is dominant over straw,s.—Shiny seed surfaceD is dominant over dull,d.—Green seed colourBr is dominant over brown;br.—Mosaic colour pattern of the seedUc is dominant over non-patterned,uc.Linkage was observed betweenS andUc, as well as betweenBr andD.  相似文献   

20.

Background

A variety of studies have evaluated the association between the − 786T>C polymorphism in the promoter region of endothelial nitric oxide synthase (eNOS) and risk of coronary artery disease (CAD). However, the results remain conflicting. To better understand the role of eNOS − 786T>C polymorphism in CAD risk, we conducted a comprehensive systematic review and meta-analysis.

Methods

Case–control, cohort or cross-sectional studies evaluating the association between eNOS − 786T>C polymorphism and CAD risk were searched in electronic databases of PubMed, ISI Web of Knowledge, Medline, Embase and Google Scholar Search (up to January 2013). Overall and subgroup analyses were performed. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the association between eNOS − 786T>C polymorphism and CAD risk. Statistical analysis was performed with Review Manager 5.0 and STATA12.0.

Results

Twenty-four studies were analyzed between 6192 CAD cases and 9281 healthy controls. The combined results of overall analysis showed significant positive associations between CAD risk and eNOS − 786T>C polymorphism in dominant model (OR = 1.45, 95% CI = 1.27–1.65), recessive model (OR = 1.37, 95% CI = 1.20–1.56), homozygote comparison (OR = 1.64, 95% CI = 1.31–2.04), heterozygote comparison (TC vs. TT, OR = 1.39, 95% CI = 1.23–1.57; CC vs. TC, OR = 1.20, 95% CI = 1.04–1.37) and allele comparison (OR = 1.35, 95% CI = 1.21–1.50). On subgroup analysis based on the ethnicity of population (Caucasians, Asians and others), significant differences were found in all genetic models for Caucasians, similar associations existed in Asians except heterozygote comparison (CC vs. TC). However, the associations were only found in dominant model, heterozygote comparison (TC vs. TT) and allele comparison for the populations named others.

Conclusions

Our investigations demonstrate the significant associations between eNOS − 786C>T polymorphism and CAD risk, and this polymorphism might become an early marker for the risk evaluation of CAD.  相似文献   

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