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1.
SUMMARY: Two different reciprocal translocations, rcp (8;14) (p21;q25) and rcp (7;13) (q13;q46), were described for the first time in Poland in the Polish Landrace and Duroc pigs. Observation of synaptonemal complexes showed the presence of a quadrivalent composed of translocational chromosomes and their homologues. Individuals carrying translocations were characterized by normal external appearance and correct semen parameters. Analysis of fertility made on the basis of litter size demonstrated that fertility decreased by 25% in the carrier of translocation rcp (8;14) and by 52% in the carrier of translocation rcp (7;13). ZUSAMMENFASSUNG: Zum erste mal festgestelte gegenseitige Translokationen bei Schweine in Polen Bein Polnischen Landras und Duroc Schweinen wurden zum erstenmal in Polen, zwei verschiedene reciproke Translokationen-rcp (8;14) (p21;q25) und rcp (7;13) (q13;q46)-festgestellt. Anhand der Beobachtungen des Synaptonemal Complex wurde die Anwesenheit eines Tetravalent nachgewiesen, welches aus Translokationschromosomen und seinen Homologen zusammengesetzt ist. Die Translokationstiere hatten normale Exterieur und Spermaparameter. Aufgrund der Fortpflanzungsergebmissen wurden verminderte Fruchtbarkeit bei Translokationstieren rcp (8;14)-um 25% und bei Translokationstieren rcp (7;13)-um 52% festgestellt. RéSUMé: Les translocations réciproques identifiées pour la prèmière fois chez les porcs levés en Pologne Chez les porcs des races Landrace et Duroc on a constaté, pour la première fois en Pologne deux translocations réciproques différentes-rcp (8;14) (p21;q25) ainsi que rcp (7;13) (q13;q46). L'observation des complexes synaptonémals a manifesté la présence du quadrivalent composé de chromosomes de translocation et de leurs homologes. Les animaux-les porteurs de la translocation ont se caractérisé par l'extérieur normal et par les paramètres réguliers du sperme. L'analyse de la fertilité expérimenté selon de la taille des portées a démontré la réduction de la fertilité pour le porteur de la translocation rcp (8;14) à 25% cependant pour les porteurs de la translocation rcp (7;13) à 52%.  相似文献   

2.
SUMMARY: Two boars of Finnish Yorkshire breed were selected for chromosomal analysis because of their small litters. One had a complex three breakpoint reciprocal translocation where the small distal chromosome segments were fused in new combinations between autosomes 2,9 and 14. This boar with a 2n = 38,XY,t(2;9;14)(q23;q22;q25) karyotype had produced approximately 3.3 piglets per litter and its fertility was reduced by 70% compared to average of litter size in Finnish Yorkshire breed pigs. In another Finnish Yorkshire breed boar, the long arm of autosome 7 had broken and attached to the terminal end of autosome 15. The boar had a 2n = 38,XY, rcp(7q-;15q+)(q24;q26) karyotype. The average of piglets per litter sired by this boar was 5.2 and the litter size was reduced by approximately 50%. The chromosomal rearrangements t(2;9;14) was inherited by four of the boar's offspring studied from two whole litters having seven piglets altogether. Meiotic chromosomes were analysed conventionally from one male translocation carrier offspring of the t(2;9;14) boar. Total sperm count and progressive motility of spermatozoa were within normal limits in one male translocation carrier offspring of the t(2;9;14) boar and in the rcp(7q-;15q+) boar. The two reciprocal translocations seem to have arisen spontaneously in these two boars. ZUSAMMENFASSUNG: Zwei F?lle reziproker Translokationen bei Ebern mit kleinen Nachkommen Würfen Von zwei Finnischen Yorkshire Ebern hatte einer drei komplexe reziproke Translokationen, wo kurze distale Chromosomensegmente zu neuen Kombinatioenen zwischen Autosomen 2, 9 und 14 fusioniert waren. Der Eber mit 2n = 38,XY,t(2;9;14)(q23;q22;q25) Karyotyp hatte Nachkommenwürfe mit etwa 3.3 Ferkel weniger und 70% Fruchtbarkeit der bei dieser Rasse normalen. In einem anderen Eber war der lange Arm von Chromosom 7 gebrochen und am Ende von Chromosom 15: 2n = 38,XY, rcp(7q-; 15q+)(q24;q26) Karyotyp. Nachkommenwurfgr??e war 5.2. Das chromosomale Rearrangement t(2;9;14) wurde an 4 Nachkommen in zwei Würfen mit zusammen 7 Ferkel vererbt. Meiotische Chromosomen wurden bei einem m?nnlichen Translokationstr?ger dieser Nachkommen analysiert. Gesamtspermienenzahl und ihre Vorw?rtsbewegung waren in normalen Grenzen bei diesem Nahkommen ebenso wie beim rcp(7q-;15q+) Eber. Die zwei reciproken Translokationen scheinen spontan entstanden zu sein.  相似文献   

3.
Cytogenetic examination of G-banded lymphocyte chromosomes of an Icelandic ram from a line with a history of poor fertility revealed a rcp (13;20) (q12;q22) translocation. Meiotic studies showed a quadrivalent configuration at diakinesis and this was confirmed by C-banding.  相似文献   

4.
The small intestine is a vital organ in animal gastrointestinal system, in which a large variety of nutrients are absorbed. To identify quantitative trait loci (QTL) for the length of porcine small intestine, phenotypic values were measured in 1034 individuals at 240 d from a White Duroc × Chinese Erhualian intercross F2 population. The length of small intestine showed strong correlation with growth traits and carcass length in the F2 population. A whole‐genome scan was performed based on 183 microsatellites covering the pig genome in the F2 population. A total of 10 QTL for this trait were identified on 8 pig chromosomes (SSC), including four 1% genome‐wide significant QTL on SSC2, 4, 7 and 8, one 5% genome‐wide significant QTL on SSC12, and five 5% chromosome‐wide significant QTL on SSC5, 7, 13 and 14. The Erhualian alleles were generally associated with shorter length of the small intestine except the alleles on SSC7 and 13. The QTL on SSC4 overlapped with the previously reported QTL for the length of small intestine. Several significant QTL on SSC2, 8, and 12 were consistent with previous reports. The significant QTL detected on SSC7 was reported for the first time. All QTL identified in this study corresponded to the known region significantly associated with growth traits, supporting the important role of the length of small intestine in pig growth.  相似文献   

5.
Pigs show extensive variation in exterior appearance. This variation has been explored as one of the selection targets to form breeding features in the pig industry. In this study, a customized Affymetrix Axiom Pig1.4M array plate was used to conduct genome‐wide association studies (GWAS) for two exterior traits—spotted coat color (SC) and facial type (FT)—in Chinese Dongxiang spotted pigs. Two and 12 single nucleotide polymorphisms (SNPs) were identified to be associated with SC and FT at the 5% genome‐wide significant level, respectively. Of these SNPs, two associated with SC were located around the DACH1 gene on Sus Scrofa chromosome (SSC)11. Eleven SNPs associated with FT were located within a 7.68 Mb region (29.03–36.71 Mb) on SSC7. Based on the GWAS results and the biological functions of genes, we highlight EDNRB as a candidate gene for SC and HMGA1 and RPS10 as the potential genes affecting facial variation. The findings contribute to the final characterization of causative genes and mutations underlying the effects of the SSC7 and SSC11 loci and improve our understanding of the genetic basis of phenotypic variation in Chinese indigenous pigs.  相似文献   

6.
Effects of genetic variation in porcine adipocyte and heart fatty acid-binding protein genes, A-FABP and H-FABP, respectively, on intramuscular fat (IMF) content and backfat thickness (BFT) were examined in F2 crossbreds of Meishan and Western pigs. The involvement of each FABP gene in IMF accretion was studied to confirm previous results for Duroc pigs. The F2 crossbred pigs were genotyped for various markers including microsatellite sequences situated within both FABP genes. Linkage analysis assigned the A-FABP and H-FABP genes to marker intervals S0001-S0217 (20 cM) on SSC4 and Sw316-S0003 (16.6 cM) on SSC6, respectively, refining previous chromosomal assignments. Next, the role of both chromosome regions/genes on genetic variation in IMF content and BFT was studied by 1) screening SSC4 and SSC6 for QTL affecting both traits by performing a line-cross analysis and 2) estimation of the effect of individual A-FABP and H-FABP alleles on both traits. In the first analysis, suggestive and chromosome-wise significant evidence for a QTL affecting IMF was detected on SSC6. The H-FABP gene is a candidate gene for this effect because it resides within the large region containing this putative QTL. The second analysis showed a considerable but nonsignificant effect of H-FABP microsatellite alleles on IMF content. Suggestive evidence for a QTL affecting BFT was found on SSC6, but H-FABP was excluded as a candidate gene. In conclusion, present and previous results support involvement of H-FABP gene polymorphisms in IMF accretion independently from BFT in pigs. Therefore, implementation of these polymorphisms in marker-assisted selection to control IMF content independently from BFT may be considered. In contrast to previous findings for Duroc pigs, no evidence was found for an effect of the A-FABP gene on IMF or BFT in this population.  相似文献   

7.
Boar reproductive traits are economically important for the pig industry. Here we conducted a genome‐wide association study (GWAS) for 13 reproductive traits measured on 205 F2 boars at day 300 using 60 K single nucleotide polymorphism (SNP) data imputed from a reference panel of 1200 pigs in a White Duroc × Erhualian F2 intercross population. We identified 10 significant loci for seven traits on eight pig chromosomes (SSC). Two loci surpassed the genome‐wide significance level, including one for epididymal weight around 60.25 Mb on SSC7 and one for semen temperature around 43.69 Mb on SSC4. Four of the 10 significant loci that we identified were consistent with previously reported quantitative trait loci for boar reproduction traits. We highlighted several interesting candidate genes at these loci, including APN, TEP1, PARP2, SPINK1 and PDE1C. To evaluate the imputation accuracy, we further genotyped nine GWAS top SNPs using PCR restriction fragment length polymorphism or Sanger sequencing. We found an average of 91.44% of genotype concordance, 95.36% of allelic concordance and 0.85 of r2 correlation between imputed and real genotype data. This indicates that our GWAS mapping results based on imputed SNP data are reliable, providing insights into the genetic basis of boar reproductive traits.  相似文献   

8.
家猪13/17罗伯逊易位染色体遗传规律的研究   总被引：8，自引：0，他引：8  
本研究采用微量全血培养法对１３／１７ 染色体易位猪的５ 种交配组合所产３４２ 头后代的染色体组型进行了分析。结果表明,家猪１３／１７ 罗伯逊易位染色体的遗传符合孟德尔遗传规律,且具有稳定的遗传性。１３／１７ 易位纯合子互交后代仍然为１３／１７ 易位纯合子;１３／１７ 易位杂合子互交后代出现１３／１７ 易位纯合子（２ｎ ＝ ３６） ,１３／１７ 易位杂合子（２ｎ ＝ ３７） 和正常核型家猪（２ｎ ＝ ３８） 三种核型,经卡方检验符合１ ２ １ 的理论比值。本文还讨论了家猪和野猪的染色体进化,１３／１７ 罗伯逊易位染色体的应用。  相似文献   

9.
Ventro‐cranial chronic pleuritis can be a result of pleuropneumonia and enzootic pneumonia. These diseases cause severe losses in intensive pig production worldwide, but host resistance is difficult to breed for. It could be beneficial to use marker‐assisted selection, and a step towards this is to identify genomic regions associated with the trait. For this purpose, 7304 pigs from 11 boar families were analysed for associations between single nucleotide polymorphisms and ventro‐cranial chronic pleuritis. The pigs were genotyped by the use of the iSelect Custom 7 K porcine SNP Chip. Quantitative trait loci (QTL), significant at the chromosome‐wide level, were identified on Sus scrofa chromosomes (SSC) 2, 4, 11, 12 and 13 in four different boar families. The QTL on SSC 4 in family G was also significant at the genome‐wide threshold according to Bonferroni correction. We have identified a number of candidate genes, but the causative mutations still need to be identified. Markers closely associated with the resistance traits have a strong potential for use in breeding towards animals with improved characteristics concerning ventro‐cranial chronic pleuritis.  相似文献   

10.
用13/17染色体易位杂合子猪互交获得的1头13/17染色体易位纯合子公猪[2n=36,XY,rob(13/17)]与4头正常核型母猪(2n=38,XX)交配,结果4头母猪全部妊娠并正常分娩.其产仔数分别为13,16,12,11,产活仔数分别为12,13,12,11;窝断奶头数分别为12,13,9,10.经核型鉴定,其后代全部为13/17易位杂合子[2n=37,XX或XY,rob(13/17)].此结果表明,13/17易位染色体的遗传完全符合孟德尔的遗传规律,13/17易位纯合子公猪具有正常的繁殖力.本杂交试验所产活仔48头,其性别比例为35?:13?,接近3:1的比例,经X~2检验不符合1:1的理论比率(X~2=10.08,P<0.01).此外,本杂交试验所产仔猪生长发育正常,并具有一定的杂合优势,这一结果为13/17易位纯合子猪的进一步推广应用,尤其是作为商品猪生产的杂交父本提供了可靠依据.  相似文献   

11.
A cytogenetical study was made of 9 descendants of a Charolais bull, heterozygous for a presumptive 1/29 translocation, three of the dams of some of these descendants, and three unrelated bulls which were mated to some of the descendants. Photographic karyotypes of Giemsa stained and C-banded chromosomes were prepared for each animal. The dams of the progeny showed no chromosomal abnormalities indicating that translocations were inherited from the sire. Three daughters of the Charolais bull and two of his grand daughters were heterozygous for the translocation, with a modal chromosomal number of 59, while the remaining three daughters and their progeny possessed normal karyotypes. No phenotypic abnormalities were observed in the animals examined. Measurements of the arms of the chromosomes suggested that the translocation chromosome (a large submetacentric) contained chromosomes 1 and 29. The submetacentric translocation chromosome had a single C-band, the two submetacentric X chromosomes showed no C-bands and each acrocentric autosome had a single C-band. All cattle heterozygous for the translocation showed normal fertility.  相似文献   

12.
Balanced autosomal translocations are a known cause for repeated early embryonic loss (REEL) in horses. In most cases, carriers of such translocations are phenotypically normal, but the chromosomal aberration negatively affects gametogenesis giving rise to both genetically balanced and unbalanced gametes. The latter, if involved in fertilization, result in REEL, whereas gametes with the balanced form of translocation will pass the defect into next generation. Therefore, in order to reduce the incidence of REEL, identification of translocation carriers is critical. Here, we report about a phenotypically normal 3‐year‐old Arabian mare that had repeated resorption of conceptuses prior to day 45 of gestation and was diagnosed with REEL. Conventional and molecular cytogenetic analyses revealed that the mare had normal chromosome number 64,XX but carried a non‐mosaic and non‐reciprocal autosomal translocation t(4;10)(q21;p15). This is a novel translocation described in horses with REEL and the first such report in Arabians. Previous cases of REEL due to autosomal translocations have exclusively involved Thoroughbreds. The findings underscore the importance of routine cytogenetic screening of breeding animals.  相似文献   

13.
The enterotoxigenic Escherichia coli (ETEC) F4ac is a major cause of diarrhoea in newborn and young pigs. The locus for the intestinal ETEC F4ac receptor (F4acR) has been mapped to pig chromosome (SSC) 13q41 with known homology to human chromosome (HSA) 3q21 and q29. However, the causative gene and mutation(s) remain unknown. The aim of this study was to characterize gene-derived markers on SSC13q41 for fine mapping of the F4acR locus, and construct a high-resolution pig–human comparative map to select positional candidate genes for F4acR. Pig-specific sequence-tagged site markers were developed for 20 genes that are located in a 6.8-Mb region on HSA3q21 and q29, and a total of 34 single-nucleotide polymorphisms (SNPs) were identified in 14 of 20 markers developed. Eighteen markers were mapped to SSC13q41, while the other two markers ( PLXNA1 and KLF15 ) were assigned to SSC13q32 and SSC7q13, respectively, by radiation hybrid mapping. This result showed that there was a small conserved segment on SSC7 corresponding to HSA3q21. A framework map comprising 18 markers on SSC13q41 was established, refining the synteny breakpoint on SSC13q41 to a region of 12.3 centiRay. The comparative radiation hybrid (RH) map revealed three interesting candidate genes for F4acR from the human genome, viz. MUC4 , MUC13 and MUC20 . Linkage analysis with six marker polymorphisms revealed that MUC4 had the most significant linkage with the F4acR locus.  相似文献   

14.
The main aim of this study was to document the prevalence of chromosomal aberrations found to date on the pig population in Spain, a country in which this production sector has a critical role, being the fourth country in the world in pig production and the second one within the European Union. The total number of animals studied was 849, and the founded frequency of carrier pigs with chromosomal alterations was 3.8%. When only the structural alterations were considered, the prevalence in males was 3.3%. This percentage is far from the 0.5% of carrier boars that has been estimated in France, a country where there is a systematic cytogenetic screening of future breeding pigs since 1992. In order to avoid the productive and economic losses caused by karyotype alterations in breeding pigs, it would be important to establish a cytogenetic screening of breeding animals at artificial insemination centres and genetic selection farms.  相似文献   

15.
Chromosomal anomalies, like Robertsonian and reciprocal translocations, represent a big problem in cattle breeding as their presence induces, in the carrier subjects, a well‐documented fertility reduction. In cattle, reciprocal translocations (RCPs, a chromosome abnormality caused by an exchange of material between non‐homologous chromosomes) are considered rare as to date only 19 reciprocal translocations have been described. In cattle, it is common knowledge that the Robertsonian translocations represent the most common cytogenetic anomalies, and this is probably due to the existence of the endemic 1;29 Robertsonian translocation. However, these considerations are based on data obtained using techniques that are unable to identify all reciprocal translocations, and thus, their frequency is clearly underestimated. The purpose of this work is to provide a first realistic estimate of the impact of RCPs in the cattle population studied, trying to eliminate the factors that have caused an underestimation of their frequency so far. We performed this work using a mathematical as well as a simulation approach and, as biological data, we considered the cytogenetic results obtained in the last 15 years. The results obtained show that only 16% of reciprocal translocations can be detected using simple Giemsa techniques, and consequently, they could be present in no <0.14% of cattle subjects, a frequency five times higher than that shown by de novo Robertsonian translocations. This data is useful to open a debate about the need to introduce a more efficient method to identify RCP in cattle.  相似文献   

16.
To understand molecular genetic characteristics of Korean pigs, the genetic relationships of nine pig breeds including two Korean pigs (Korean native pig and Korean wild pig), three Chinese pigs (Min pig, Xiang pig, and Wuzhishan pig), and four European breeds (Berkshire, Duroc, Landrace, and Yorkshire) were characterized from a 16-microsatellite loci analysis. The mean heterozygosity within breeds ranged from 0.494 to 0.703. Across multiple loci, significant deviation from Hardy-Weinberg equilibrium was observed in most pig breeds, except for two Chinese pigs (Min pig and Wuzhishan pig). This deviation was in the direction of heterozygote deficit. Across population loci, 36 of 144 significantly deviated (P < 0.05) from Hardy-Weinberg equilibrium. The mean FST, a measure of genetic divergence among subpopulations, of all loci indicated that 26.1% of total variation could be attributed to the breed difference. Relationship trees based on the Nei's DA genetic distance and scatter diagram from principal component analysis consistently displayed pronounced genetic differentiation among the Korean wild pig, Xiang pig, and Wuzhishan pig. Individual assignment test using a Bayesian method showed 100% success in assigning Korean and Chinese individual pigs into their correct breeds of origin and 100% exclusion success from all alternative reference populations at P < 0.001. These findings indicate that the Korean native pig has been experiencing progressive interbreeding with Western pig breeds after originating from a North China pig breed with a black coat color. Considering the close genetic relationship of Korean pigs to the Western breeds such as Berkshire and Landrace, our findings can be used as valuable genetic information for the preservation and further genetic improvement of the Korean native pig.  相似文献   

17.
Peripheral blood samples from a 13-year-old Thoroughbred mare were submitted for chromosome analysis. The mare had a poor reproduction record only producing four live foals during her 10 years as a broodmare. She had remained barren or experienced early embryonic loss in the other 6 years. Chromosomal analysis revealed the mare carried a rare nonreciprocal translocation involving chromosomes 2 and 13 [64,XX,t(2;13)]. Fluorescence in situ hybridization with probes specific for horse chromosomes 2 and 13 were used to confirm the nonreciprocal translocation. Both conventional and molecular cytogenetic techniques are important for identifying and characterizing chromosomal abnormalities in horses with poor reproductive performance, particularly in mares experiencing repeated early embryonic loss.  相似文献   

18.
Understanding of the genetic control of female reproductive performance in pigs would offer the opportunity to utilize natural variation and improve selective breeding programs through marker-assisted selection. The Chinese Meishan is one of the most prolific pig breeds known, farrowing 3 to 5 more viable piglets per litter than Western breeds. This difference in prolificacy is attributed to the Meishan's superior prenatal survival. Our study utilized a 3-generation resource population, in which the founder grandparental animals were purebred Meishan and Duroc pigs, in a genome scan for QTL. Grandparent, F1, and F2 animals were genotyped for 180 microsatellite markers. Reproductive traits, including number of corpora lutea (number of animals = 234), number of fetuses per animal (n = 226), number of teats (n = 801), and total number born (n = 288), were recorded for F2 females. Genome-wide significance level thresholds of 1, 5, and 10% were calculated using a permutation approach. We identified 9 QTL for 3 traits at a 10% genome-wise significance level. Parametric interval mapping analysis indicated evidence of a 1% genome-wise significant QTL for corpora lutea on SSC 3. Nonparametric interval mapping for number of teats found 4 significant QTL on chromosomes SSC3 (P < 0.01), SSC7 (P < 0.01), SSC8 (P < 0.01), and SSC12 (P < 0.05). Partial imprinting of a QTL affecting teat number (P < 0.10) was detected on SSC8. Using the likelihood-ratio test for a categorical trait, 2 QTL for pin nipples were detected on SSC2 and SSC16 (P < 0.01). Fine mapping of the QTL regions will be required for their application to introgression programs and gene cloning.  相似文献   

19.
In the mouse, homozygous animals for the high growth mutation show a 30–50% increase in growth without becoming obese. This region is homologous to the distal part of pig chromosome 5 (SSC5). A previous genome scan detected several quantitative trait loci (QTL) in this region for body composition and meat quality using a three generation Berkshire × Yorkshire resource family. In this study, the effects on swine growth, fat and meat quality traits of three genes previously identified within the mouse high growth region were analysed. The genes studied were CASP2 and RIPKI domain containing adaptor with death domain ( CRADD ), suppressor of cytokine signalling 2 ( SOCS2 ) and plexinC1 ( PLXNC1 ). In addition, the influence of two other genes located very close to this region, namely the plasma membrane calcium-transporting ATPase 1 ( ATP2B1 ) and dual specificity phosphatase 6 ( DUSP6 ) genes, was also investigated. Single nucleotide polymorphisms were identified and used to map these genes to the QTL region on SSC5. Results indicate significant associations between these genes and several phenotypic traits, including fat deposition and growth in pigs. The present study suggests associations of these genes with swine fat and growth related traits, but further studies are needed in order to clearly identify the genes involved in the regulation of the QTL located on SSC5.  相似文献   

20.
In this study, the karyotypes of 14 piglets from four different litters produced by intracytoplasmic sperm injection (ICSI) and embryo transfer were analysed. The chromosome analysis was based on a classical cytogenetic examination following the standard protocols of lymphocyte cultures. Two cases of reciprocal translocation [(4; 7)(p+; q-) and (2; 8)(q-; q+)] were detected in two female transgenic piglets. These animals showed neither anatomical nor physiological alterations and had normal growth. To our knowledge, this is the first karyotype study of piglets produced by ICSI.  相似文献   

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