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1.
Female predominance among carriers of reciprocal translocations (rec) has been commonly explained by male sterility, although appropriate comparative studies had not been carried out. The objectives of this study were comparative analysis of rates of carriers of balanced chromosomal rearrangement among patients with infertility and among patients with recurrent miscarriages and comparative analysis of maleto-female ratio (sex ratio, SR) in the carriers. Metaanalysis of data from 34 publications on prevalence of chromosomal rearrangements in couples with reproductive failures showed that among couples with infertility, a carrier of reciprocal translocation was found in 0.48% (74/15306) of males and in 0.41% (64/15456) of females, SR =1.17, not different statistically from the population value of 1.06 (p = 0.36). Carriers of Robertsonian translocations (rob) were detected in 0.58% of males and in 0.11% of females, SR = 5.3 (p = 5 × 10–13). Carriers of an inversion (inv) were found at a slightly lower rate among infertile males compared to females, 0.16% vs 0.27%, SR = 0.59 (p = 0.020). Among patients with miscarriages, carriers of rec were detected at a significantly higher rate compared to patients with infertility, in 0.78% (151/19353) of males and in 1.42% (281/19737) of females, SR = 0.55 (p = 1 × 10–9). Carriers of rob were found in 0.33% of male patients and in 0.6% of female patients, SR = 0.56 (p = 9.7 × 10–5). Rates of male and female carriers of inv were 0.17 and 0.20%, respectively. The data obtained corroborate with the observation of female predominance among fertile carriers of rob due to male sterility. However, female predominance among fertile carriers of rec cannot be explained by the same reason. Firstly, there is no significant male prevalence among infertile carriers, secondly, the rate of rec carriers among infertile males is lower compared to that among fertile patients. This phenomenon might be explained by factors inherent to oogenesis affecting meiotic segregation of rearranged.  相似文献   

2.
The predominance of females among reciprocal (rec) translocation carriers, which have problems with reproduction in the anamnesis, is well established and usually accounts for the sterility of male carriers of this type of translocations. However, no careful comparative studies have been performed. Meta-analysis of the data on the examined pairs with reproduction problems shows that, among patients with infertility, the frequency of rec carriers was observed in 0.48% (74/15304) of men and in 0.41% (64/15454) of women; the sex ratio (SR) was 1.17, which does not differ significantly from the population value, 1.06 (p = 0.36). Robertsonian translocations (rob) were observed in 0.58% of men and in 0.11% of women; SR = 5.3 (p = 5 × 10–13) in this group. Inversions (inv) were more often detected in women than in men, 0.14 and 0.27%, SR = 0.59 (p = 0.020). Among patients with habitual miscarriages, the frequencies of rec carriers were significantly higher than in patients with infertility: in 0.78% (151/19353) of men and in 1.42% (281/19737) of women, GR = 0.55 (p = 10–9). Carriers of rob were found in 0.33% of men and 0.60% of women, SR = 0.55 (p = 9.7 × 10–5). The frequency of inv was 0.17 and 0.20%, respectively. The results supports the notion that the predominance of women among fertile carriers of rob is caused by the sterility of male carriers of such rearrangements. However, the predominance of women among fertile carriers of rec cannot be due to this reason. The first reason is because there is no significant prevalence of men over women among infertile carriers of such type translocations. The second reason is because the frequency of rec male carriers among patients with infertility is significantly lower than their frequency among fertile carriers. It is likely that the reason for the observed phenomenon is the inherent oogenesis factors which affect segregation of the aberrant chromosomes.  相似文献   

3.
Robertsonian translocations (rob) are essential in the etiology of congenital malformations and reproductive disorders. However, to date, there has been no systematic comparative analysis of both the frequency and spectrum of rob in different carrier populations. Also, due attention was not paid to the phenomenon of the exceptional rarity of some types of rob. In this paper, the spectrum of rob was determined in the reference group (newborn carriers from the general population and carriers diagnosed prenatally for indications other than family rearrangement) in comparison with groups of carriers with reproductive disorders (infertility and pregnancy loss). The overall rates of rob in the studied groups were calculated as 1.05, 3.3, and 5‰, respectively. It was suggested that homologous translocations do not cause disturbances in spermatogenesis. A rarity of some certain types of translocation could be explained by selection.  相似文献   

4.

Background

The aim of this study was to determine the genotype distribution and allelic frequencies of ACE (I/D), AGTR1 (A +1166 C), BDKRB2 (+9/?9) and LEP (G–2548A) genomic variations in 175 Greek athletes who excelled at a national and/or international level and 169 healthy Greek adults to identify whether some particular combinations of these loci might serve as predictive markers for superior physical condition.

Results

The D/D genotype of the ACE gene (p = 0.034) combined with the simultaneous existence of BDKRB2 (+9/?9) (p = 0.001) or LEP (G/A) (p = 0.021) genotypes was the most prevalent among female athletes compared to female controls. A statistical trend was also observed in BDKRB2 (+9/?9) and LEP (G–2548A) heterozygous genotypes among male and female Greek athletes, and in ACE (I/D) only in male athletes. Finally, both male and female athletes showed the highest rates in the AGTR1 (A/A) genotype.

Conclusions

Our results suggest that the co-existence of ACE (D/D), BDKRB2 (+9/?9) or LEP (G/A) genotypes in female athletes might be correlated with a superior level of physical performance.
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5.
Long-termed intersexual friendly relationships between males and females of the Brauner’s lizard are characterized by high levels of spatial association and high frequency of affiliative behavior between partners (see report 1). In present article we consider changes in the frequency of affiliative behavior in males (Am) and females (Af) after the first appearance of female on the male’s territory and conditions for the transition of lizard to stable residency (SR). Generally, Am becomes stable during the first days of initial period and does not change later. This fact suggests that in most instances male’s choice criteria are some peculiarities of the female’s exterior. In the initial period, Af is always low, however, gradually rises to the level of Am if Am is high. The main condition of female’s SR is high Am of the owner of the territory where female establishes her comfort areas. Hence, social partner choice in female is based on male’s behavior, and high Am triggers the formation of friendly interrelations. Significant correlation between social and sexual interrelations is absent. As can be judged by female’s reactions to male’s sexual behavior, his sexual activity is rather a factor of social disintegration. Structure of costs for social partner search is different in males and females, and these differences well harmonize with differences in gender strategies of partner choice. The social strategies are well interpreted in terms of the optimal foraging theory.  相似文献   

6.
7.
Myristica fatua is a dioecious specialist species restricted to the endangered, freshwater Myristica swamp forests in the Western Ghats, India. Earlier studies have alluded to pollination by deception in members of the Myristica genus, and thus we examined the pollination ecology comprising floral biology, flower production, flower visitors, and reproductive success in M. fatua and inferred the potential strategies that could permit such deception in this habitat specialist tree. Male flowers provide pollen rewards for an extended period of time while female flowers are rewardless and both sexes are visited by generalist insects, mainly by honeybees and stingless bees. Bee visits were significantly more frequent and longer on male than on female flowers as bees collected pollen from male flowers. We found that flower production patterns create a preponderance of males compared to females in the swamp populations. Using a model of honeybee color vision, we found the distance between the color loci of male and female flowers and based on minimum visual angle subtended by these flowers, we suggest that the two floral sexes cannot be discriminated by bees. Bees are likely deceived by the perceptual similarity of rewardless female flowers to pollen-offering male flowers and pollination is the consequence of foraging errors made by pollinators that encounter largely male–rarely female flower mosaics as they forage among clump-distributed M. fatua trees in the swamp habitat.  相似文献   

8.
There is growing evidence that serum levels of various inflammation markers are associated with personality traits. However, only few studies investigated the link between genetic variants of cytokine encoding genes and psychological characteristics. In this study, we examined genotypes in 297 individuals to assess the association between common variants of interleukin 4 (IL-4) and interleukin 10 (IL-10) genes and basic personality traits of extraversion and neuroticism, measured using the Eysenck Personality Questionnaire (EPQ). We found that, in homozygous female carriers of high expression alleles Т (IL-4 C-589T) and G (IL-10 G-1082A), neuroticism scores were higher (p = 0.045 and p = 0.08, respectively). In turn, extraversion scores were significantly higher in both male and female carriers of heterozygous variants CT and GA (p = 0.01). Our results are in accordance with the behavioral immune system hypothesis, and the general paradigm on the role of personality traits in health and longevity.  相似文献   

9.
In the field, male pheromone attracts stink bugs to meet on the same plant and triggers females to call a male by the emission of the calling song. As first among Pentatomidae we describe female rivalry in Chinavia impicticornis, C. ubica and Euschistus heros. Rivalry starts in C. impicticornis by synchronized exchange of the first type of the female calling song pulse trains and proceeds by one of them either to change pulse trains from the first to the second type or to produce readily repeated single pulses. Both reactions either inhibit calling of the rival female or trigger her to respond by alternation with the second type of the calling song pulse trains. Female rivalry in C. ubica differs by the emission of the rival song that replaces alternation with the second type of the calling song typical for C. impicticornis. E. heros females synchronize pulses of the calling song duets and induce emission of the female rival song by one of them that partly inhibits singing of the other. These competitive interactions in Chinavia species reduce the proportion of couples when compared with single couples on a plant. Contrary to both Chinavia species, E. heros female rivalry does not inhibit male response, male signals overlap female emissions and create complex vibrations with modified amplitude modulation pattern caused by interference.  相似文献   

10.
11.

Background

Robertsonian translocations (RobT) are common structural chromosome rearrangements where carriers display a majority of chromosomally balanced spermatozoa from alternate segregation mode. According to some monotony observed in the rates of balanced segregation, is sperm FISH analysis obsolete for RobT carriers?

Methods

Retrospective cohort research study on 23 patients analyzed in our center from 2003 to 2017 and compared to the data of 187 patients in literature from 1983 to 2017.Robertsonian translocation carriers were divided in six groups according to the chromosomes involved in the translocation: 9 patients from our center and 107 from literature carrying 45,XY,der(13;14) karyotype, 3 and 35 patients respectively with 45,XY,der(14;21), 5 and 11 patients respectively with 45,XY,der(13;15), 4 and 7 patients respectively with 45,XY,der(14;15), 1 and 4 patients respectively with 45,XY,der(13;22),and 1 and 10 patients respectively with 45,XY,der(14;22).

Results

Alternate segregation mode is predominant in our group of Robertsonian translocation carriers with 73.45% ±8.05 of balanced spermatozoa (min 50.92%; max 89.99%). These results are compliant with the data from literature for all translocations types (p?>?0.05) and are consistent among the different types of Robertsonian translocations (p?>?0.05) except for der(13;15) that exhibit lower balanced spermatozoa rates (p?<?0.05 versus der(13;14), der(14;21), (13;21) and der(15;22)). Normozoospermic patients also display a significantly (p?<?0.01) higher rate of balanced sperm cells than patients with abnormal seminograms whatever the defect implied.

Conclusions

According to the discrepancies observed between der(13;15) and all the other Rob T carriers, the differences observed among patients presenting normal and abnormal sperm parameters and the input in genetical counselling, sperm FISH does not seem obsolete for these patients. Moreover, it seems important to collect more data for rare RobT.
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12.
Alternative splicing is a widely used mechanism of gene regulation in sex determination pathways of Insects. In species from orders as distant as Diptera, Hymenoptera and Coleoptera, female differentiation relies on the activities of conserved splicing regulators, TRA and TRA-2, promoting female-specific expression of the global effector doublesex (dsx). Less understood is to what extent post-translational modifications of splicing regulators plays a role in this pathway. In Drosophila melanogaster phosphorylation of TRA, TRA-2 and the general RBP1 factor by the LAMMER kinase doa (darkener of apricot) is required for proper female sex determination. To explore whether this is a general feature of the pathway we examined sex-specific differences in phosphorylation levels of SR splicing factors in the dipteran species D. melanogaster, Ceratitis capitata (Medfly) and Musca domestica (Housefly). We found a distinct and reproducible pattern of male-specific phosphorylation on protein extracts enriched for SR proteins in C. capitata suggesting that differential phosphorylation may also contribute to the regulation of sex-specific splicing in the Medfly.  相似文献   

13.
The paper reports a search for association between the relative bone tissue mass (percent of total body mass, %BT) and FokI (rs10735810), BsmI (rs1544410), and TaqαI (rs731236) vitamin D receptor gene polymorphisms. The group of apparently healthy young adults born in the central and northern regions of European Russia included 61 men and 60 women aged 16–23 years. No statistical association was detected between the FokI polymorphism and %BT. The carriers of the BsmI *A allele exhibited a higher %BT (p = 0.0172) compared to the subjects bearing the BsmI *G*G allele. The subjects with the *C*C TaqαI genotype were characterized by increased %BT compared to the carriers of the *T allele (p = 0.0018). The data are in good correspondence with the results obtained in the studies involving apparently healthy representatives of Central European and Northern European populations of the corresponding age.  相似文献   

14.

Background

Obligate pollination mutualisms (OPMs) are specialized interactions in which female pollinators transport pollen between the male and female flowers of a single plant species and then lay eggs into those same flowers. The pollinator offspring hatch and feed upon some or all of the developing ovules pollinated by their mothers. Strong trait matching between plants and their pollinators in OPMs is expected to result in reciprocal partner specificity i.e., a single pollinator species using a single plant species and vice versa, and strict co-speciation. These issues have been studied extensively in figs and fig wasps, but little in the more recently discovered co-diversification of Epicephala moths and their Phyllanthaceae hosts. OPMs involving Epicephala moths are believed occur in approximately 500 species of Phyllanthaceae, making it the second largest OPM group after the Ficus radiation (>?750 species). In this study, we used a mixture of DNA barcoding, genital morphology and behavioral observations to determine the number of Epicephala moth species inhabiting the fruits of Breynia oblongifolia, their geographic distribution, pollinating behavior and phylogenetic relationships.

Results

We found that B. oblongifolia hosts two species of pollinator that co-occurred at all study sites, violating the assumption of reciprocal specificity. Male and female genital morphologies both differed considerably between the two moth species. In particular, females differed in the shape of their ovipositors, eggs and oviposition sites. Phylogenetic analyses indicated that the two Epicephala spp. on B. oblongifolia likely co-exist due to a host switch. In addition, we discovered that Breynia fruits are also often inhabited by a third moth, an undescribed species of Herpystis, which is a non-pollinating seed parasite.

Conclusions

Our study reveals new complexity in interactions between Phyllantheae and Epicephala pollinators and highlights that host switching, co-speciation and non-pollinating seed parasites can shape species interactions in OPMs. Our finding that co-occurring Epicephala species have contrasting oviposition modes parallels other studies and suggests that such traits are important in Epicephala species coexistence.
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15.
16.
A striking infertile phenotype has been discovered in the DDK strain of mouse. The DDK females are usually infertile when crossed with males of other inbred strains, whereas DDK males exhibit normal fertility in reciprocal crosses. This phenomenon is caused by mutation in the ovum (Om) locus on chromosome 11 and known as the DDK syndrome. Previously, some research groups reported that the embryonic mortality deviated from the semilethal rate in backcrosses between heterozygous (Om/ + ) females and males of other strains. This embryonic mortality exhibited an aggravated trend with increasing background genes of other strains. These results indicated that some modifier genes of Om were present in other strains. In the present study, a population of N2 (Om/ + ) females from the backcrosses between C57BL/6J (B6) and F1 (B6 ♀ × DDK ♂) was used to map potential modifier genes of Om. Quantitative trait locus showed that a major locus, namely Amom1 (aggravate modifier gene of Om 1), was located at the middle part of chromosome 9 in mice. The Amom1 could increase the expressivity of Om gene, thereby aggravating embryonic lethality when heterozygous (Om/ +) females mated with males of B6 strain. Further, the 1.5 LOD-drop analysis indicated that the confidence interval was between 37.54 and 44.46 cM, ~6.92 cM. Amom1 is the first modifier gene of Om in the B6 background.  相似文献   

17.
In patients with haematological malignancies, the bowel remains the main source of Escherichia coli bloodstream infections. We present the clinical example of recurrent bowel-blood translocations of E. coli with the unique virulence characteristics in a 55-year-old male with the diagnosis of acute myeloid leukaemia. The virulent factors profile of examined strains confirmed that the co-existence of genes papC, sfa, usp and cnf1, encoding virulence factors, predisposes E. coli to translocation from the gastrointestinal tract to the vascular bed. The close cooperation between haematologists and microbiologists is essential to improve the outcome of patients colonised with highly pathogenic strains.  相似文献   

18.
The Western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), is one of the most destructive sucking pests of flowering plants. We examined behavioral responses of F. occidentalis adults to the floral volatiles of Rosa chinensis, Gardenia jasminoides, and Tagetes erecta in a Y-tube olfactometer with background visual cues (green, red, white, yellow, and blue backgrounds). The results show that F. occidentalis adults had similar responses under all the different background colors, but the responses by sex varied significantly when offered floral volatile or clean air. In pairings of floral volatiles, female F. occidentalis adults presented significant preferences (R. chinensis > G. jasminoides > T. erecta) in each treatment, while male F. occidentalis adults had no significant preference. Furthermore, the responses of female F. occidentalis adults to the three different floral volatiles compared with each other were greater under green and blue backgrounds than red, white, or yellow backgrounds. However, the responses of male F. occidentalis adults to floral volatiles were similar to all five backgrounds. These results indicate that female thrips could discriminate different floral volatiles, while male thrips could not. Both male and female thrips performed steady preferences of floral volatiles under all the five visual backgrounds, and the behavioral responses of female thrips to the floral volatiles could be enhanced under the green and blue backgrounds. These findings could hopefully aid in the development of effective trapping and monitoring strategies for this pest.  相似文献   

19.
Capsicum baccatum L., one of five domesticated species of Capsicum, is a valuable species in chili pepper breeding. In particular, it is a source of disease resistance against anthracnose and powdery mildew. Genetic maps and molecular markers are important to improve the efficiency of crop breeding programs. Recently, using genetic maps several researchers have identified quantitative trait loci (QTLs) for important horticultural traits and have cloned genes of interest. In this study, we constructed a genetic map of C. baccatum in an intraspecific population from a cross between ‘Golden-aji’ and ‘PI594137.’ A total of 395 high-resolution melting markers were developed based on single-nucleotide polymorphisms identified by comparing genome sequences generated through next-generation resequencing of the parents, ‘Golden-aji’ and ‘PI594137.’ The genetic linkage map contained 12 linkage groups, covered a total distance of 1056.2 cM, and had an average distance of 2.67 cM between markers. In addition, the final map was compared to the reference physical map of C. annuum ‘CM334.’ Interestingly, two major reciprocal translocations between chromosomes 3 and 5 and between chromosomes 3 and 9 were found, suggesting that these translocations might act as a genetic barrier between C. annuum and C. baccatum. Translocations between chromosomes 1 and 8 were also observed, as were previously reported in C. chinense, C. frutescens, and wild C. annuum. The synteny of other chromosomes was maintained, on the whole, except for several small inversions. The information on this genetic map will be helpful to analyze QTLs for important traits such as anthracnose resistance in C. baccatum and to study the causes of genetic barriers between C. annuum and C. baccatum.  相似文献   

20.
The molecular-genetic testing of the polymorphic rs2981579 (C>T) locus of the FGFR2 gene as the marker of increased predisposition to the development of mesial occlusion was carried out in 110 patients with mesial occlusion and 103 general-population control subjects from Ukraine. It was shown that polymorphism rs2981579 in gene FGFR2 is associated with mesial occlusion (OR = 1.67, 95% CI = 1.14–2.45, p = 0.009). Compared to CC carriers, TT+CT carriers had a 3.21-fold higher risk of mesial occlusion (95% CI = 1.57–6.57, p = 0.001). We found the protective effect of the homozygous allele C on mesial occlusion development (OR = 0.31, p = 0.001). This is the first published data on FGFR2 polymorphisms rs2981579 (C>T) in patients with mesial occlusion.  相似文献   

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