Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overf...Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.展开更多
To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The ...To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity （GS） values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions （0.447）, while Australia accessions have the furthest distance （0.503）. A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.展开更多
The aim of genetic monitoring is to checking the genetic contamination within inbred starains,which insures that the strains according with the require of colony . At present the methods based on allozyme biochemistry...The aim of genetic monitoring is to checking the genetic contamination within inbred starains,which insures that the strains according with the require of colony . At present the methods based on allozyme biochemistry are the National Standard instructed. methods that using microsatellite DNA would be more useful for genetic monitoring than methods based on allozyme biochemistry because the genome itself is being tested rather than a protein product and a larger portion of the genome can be sampled, and easy to distinguish. methods that using microsatellite DNA had abundant microsatellite loci(over 7300,before 1999) can be identified. Applying enough microsatellite loci will present abundant straps and well polymorphism, which can reflection inherit and variation of roundly genene.In addition, this novel approach allows the rapid, sensitive,convenientand accuracy, even individual identificaton. So we should select microsatellite DNA which is polymorphisms as genetic monitoring markers to determining the strains’origin and genetic background of inbred mice. Untill now Only feasibility has been reported,and in which microsatellite DNA loci have not enough polymorphisms to distinguish genetic differences.Articles on standards and practicality have not been founded in our country. With the optimization of components of reaction buffer and amplificaton parameter,PCR for amplification microsatellite DNA was finally set up.Using the techniques microsatellite DNA can amplified efficaciously. The final concentrations of Mg 2+ was 1 .5—3.0 mmol/L,annealing temperature was 50℃—65℃.The condition for the PCR amplify were ,94℃for 3min,30cycles of 94℃ for 30s, 50℃—65℃ for 30s,72℃ for 1min,finally at 72℃ for 1min,then store at 4℃. Ten kinds of inbred strain mice including C57BL/6J,C3H/He, TA1,TA 2,615,BALB/c ,DBA/2N,129/Sv,FVB/N,AMMS/1 were investigated by PCR analysis. 14 microsatellites DNA loci on different chromosomes which we selected applied in genetic monitoring is the first time on 10 commonly used inbred mouse strains. It showed that all these microsatellites DNA loci display single allelic gene band. Fourteen loci are polymorphisms, among which the polymorphisms of D1Mit365、D2Mit30、D3Mit51、D5Mit48、D6Mit102、D10Mit180、D11Mit128、D12Mit147、D14Mit102 and D17Mit36 are significant .These results suggest that these mice tested meet the request of inbred strain. The genetic background of TA1 was similar with that of TA 2,the similarity indices were from 14.3%( C57 between 129)to 92.9%( TA1 between TA 2).This means that TA1 and TA 2 had closer genetic relationship, C57 and 129 had farther relationship. In addition , the similarity indices of BALB/c and BALB/c-nu-nu was 92.9%,All show that strains or substrains can be distinguished by microsatellites DNA. Screened loci showing marked polymorphisms typically reflect the speciality of strains and genetic backgrounds, which could be used in determining the strains’ origin and genetic background of mice.展开更多
BACKGROUND Colorectal cancer(CRC)ranks third in terms of incidence and second in mortality worldwide.In CRC,the silencing of mismatch repair genes,including the mutL homolog 1(hMLH1)has been linked to microsatellite i...BACKGROUND Colorectal cancer(CRC)ranks third in terms of incidence and second in mortality worldwide.In CRC,the silencing of mismatch repair genes,including the mutL homolog 1(hMLH1)has been linked to microsatellite instability(MSI),the lengthening or shortening of microsatellite repeats.Very limited data have been presented so far on the link of hMLH1 methylation and MSI in Southeast Asia populations with sporadic CRC,and on its clinical significance.AIM To investigate the significance of the MSI status and hMLH1 methylation in CRC Filipino patients.METHODS Fifty-four sporadic CRC patients with complete clinical data were included in this study.Genomic DNA from CRC tumor biopsies and their normal tissue counterparts were profiled for MSI by high resolution melting(HRM)analysis using the Bethesda Panel of Markers(BAT25,BAT26,D2S123,D5S346,and D17S250).hMLH1 methylation screening was performed using bisulfite conversion and methylation specific polymerase chain reaction.Statistical analysis was conducted to calculate their associations to clinicopathological characteristics and survival relevance(Kaplan-Meier curves and the log-rank test).RESULTS hMLH1 methylation was observed in 9%and 35%of CRC and normal samples,respectively.Higher incidence of consistently methylated hMLH1 found in both normal and CRC was noticed for relation to location of tumor(P<0.05).As for MSI status,D2S123 the most common unstable microsatellite and MSI-high(MSIH)was the most common MSI profile,counted for 46%and 50%of normal and CRC tissues,respectively.The presence of MSI-low(MSI-L)and microsatellite stable(MSS)was 43%and 11%for normal,and 31%and 19%for CRC samples.The mean month of patients’survival was shorter in patients whose normal and tumor tissues had methylated compared to those with unmethylated hMLH1 and with MSI-H compared to those with MSI-L/MSS(P<0.05).This was supported by significant difference in Kaplan-Meier with log-rank analysis.This data indicated that hMLH1 methylation and high MSI status have prognostic value.CONCLUSION This study showed the clinical significance of hMLH1 methylation and MSI status in sporadic CRC Filipino patients,especially in the normal part of the tumor.展开更多
基金The National Natural Science Foundation of China under contract Nos 32170536 and 31672257。
文摘Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.
基金supported by the National Natural Science Foundation of China (30800700)the China Agriculture Research System
文摘To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity （GS） values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions （0.447）, while Australia accessions have the furthest distance （0.503）. A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.
文摘The aim of genetic monitoring is to checking the genetic contamination within inbred starains,which insures that the strains according with the require of colony . At present the methods based on allozyme biochemistry are the National Standard instructed. methods that using microsatellite DNA would be more useful for genetic monitoring than methods based on allozyme biochemistry because the genome itself is being tested rather than a protein product and a larger portion of the genome can be sampled, and easy to distinguish. methods that using microsatellite DNA had abundant microsatellite loci(over 7300,before 1999) can be identified. Applying enough microsatellite loci will present abundant straps and well polymorphism, which can reflection inherit and variation of roundly genene.In addition, this novel approach allows the rapid, sensitive,convenientand accuracy, even individual identificaton. So we should select microsatellite DNA which is polymorphisms as genetic monitoring markers to determining the strains’origin and genetic background of inbred mice. Untill now Only feasibility has been reported,and in which microsatellite DNA loci have not enough polymorphisms to distinguish genetic differences.Articles on standards and practicality have not been founded in our country. With the optimization of components of reaction buffer and amplificaton parameter,PCR for amplification microsatellite DNA was finally set up.Using the techniques microsatellite DNA can amplified efficaciously. The final concentrations of Mg 2+ was 1 .5—3.0 mmol/L,annealing temperature was 50℃—65℃.The condition for the PCR amplify were ,94℃for 3min,30cycles of 94℃ for 30s, 50℃—65℃ for 30s,72℃ for 1min,finally at 72℃ for 1min,then store at 4℃. Ten kinds of inbred strain mice including C57BL/6J,C3H/He, TA1,TA 2,615,BALB/c ,DBA/2N,129/Sv,FVB/N,AMMS/1 were investigated by PCR analysis. 14 microsatellites DNA loci on different chromosomes which we selected applied in genetic monitoring is the first time on 10 commonly used inbred mouse strains. It showed that all these microsatellites DNA loci display single allelic gene band. Fourteen loci are polymorphisms, among which the polymorphisms of D1Mit365、D2Mit30、D3Mit51、D5Mit48、D6Mit102、D10Mit180、D11Mit128、D12Mit147、D14Mit102 and D17Mit36 are significant .These results suggest that these mice tested meet the request of inbred strain. The genetic background of TA1 was similar with that of TA 2,the similarity indices were from 14.3%( C57 between 129)to 92.9%( TA1 between TA 2).This means that TA1 and TA 2 had closer genetic relationship, C57 and 129 had farther relationship. In addition , the similarity indices of BALB/c and BALB/c-nu-nu was 92.9%,All show that strains or substrains can be distinguished by microsatellites DNA. Screened loci showing marked polymorphisms typically reflect the speciality of strains and genetic backgrounds, which could be used in determining the strains’ origin and genetic background of mice.
基金Department of Science and Technology and the Philippine Council for Health Research and Development(DOST-PCHRD)(to Cabral LKD)St.Luke’s Medical Center,Manila,Philippinesand Regione Autonomo FVG in Progetti Internazionali 2021 to the FIF,No.DGR 189 dd 12/2/21.
文摘BACKGROUND Colorectal cancer(CRC)ranks third in terms of incidence and second in mortality worldwide.In CRC,the silencing of mismatch repair genes,including the mutL homolog 1(hMLH1)has been linked to microsatellite instability(MSI),the lengthening or shortening of microsatellite repeats.Very limited data have been presented so far on the link of hMLH1 methylation and MSI in Southeast Asia populations with sporadic CRC,and on its clinical significance.AIM To investigate the significance of the MSI status and hMLH1 methylation in CRC Filipino patients.METHODS Fifty-four sporadic CRC patients with complete clinical data were included in this study.Genomic DNA from CRC tumor biopsies and their normal tissue counterparts were profiled for MSI by high resolution melting(HRM)analysis using the Bethesda Panel of Markers(BAT25,BAT26,D2S123,D5S346,and D17S250).hMLH1 methylation screening was performed using bisulfite conversion and methylation specific polymerase chain reaction.Statistical analysis was conducted to calculate their associations to clinicopathological characteristics and survival relevance(Kaplan-Meier curves and the log-rank test).RESULTS hMLH1 methylation was observed in 9%and 35%of CRC and normal samples,respectively.Higher incidence of consistently methylated hMLH1 found in both normal and CRC was noticed for relation to location of tumor(P<0.05).As for MSI status,D2S123 the most common unstable microsatellite and MSI-high(MSIH)was the most common MSI profile,counted for 46%and 50%of normal and CRC tissues,respectively.The presence of MSI-low(MSI-L)and microsatellite stable(MSS)was 43%and 11%for normal,and 31%and 19%for CRC samples.The mean month of patients’survival was shorter in patients whose normal and tumor tissues had methylated compared to those with unmethylated hMLH1 and with MSI-H compared to those with MSI-L/MSS(P<0.05).This was supported by significant difference in Kaplan-Meier with log-rank analysis.This data indicated that hMLH1 methylation and high MSI status have prognostic value.CONCLUSION This study showed the clinical significance of hMLH1 methylation and MSI status in sporadic CRC Filipino patients,especially in the normal part of the tumor.
