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1.
The human secretor type α(1,2)fucosyltrans-ferase gene (FUT2) polymorphism was investigated in Xhosa and Caucasian populations of South Africa by polymerase chain reaction–restriction fragment length polymorphism and DNA sequencing. Six new base substitutions were found in the coding region of FUT2. A single base (C) deletion at nucleotide 778, which led to a frame shift and produced a stop codon at codon 275, was responsible for the enzyme inactivation. Three nonsynonymous base substitutions, A40G (Ile14Val), C379T (Arg127Cys), and G481A (Asp161Asn), and two synonymous base substitutions, A375G (Glu125) and C480T (His160), were also identified in functional alleles. As a result, seven new alleles, Se 40 , Se 481 , Se 40,481 , Se 357,480 , Se 357,379,480 , Se 375 , and se 357,480,778 were identified. Population studies revealed that an allele containing a nonsense mutation G428A (Trp143stop) (se 428 ) was the common null allele in both Xhosa and Caucasian populations, whereas an allele containing a missense A385T (Ile129Phe) mutation (se 357,385 ), which is the common null allele in Orientals, was found to be absent from both populations. The heterozygosity rates of FUT2 genotypes were as high as 0.75 in the Xhosa population and 0.65 in the Caucasian population. Therefore, the extensive polymorphism and race specificity of the FUT2 gene make it suitable for application as a new tool in genetic studies of modern human evolutionary history. Received: 23 March 1998 / Accepted: 9 May 1998  相似文献   

2.
TheSe wA385T mutation of the FUT2 gene was found to correlate with both the erthrocyte Le(a+b+) and/or salivary ABH partial-secretor phenotypes of Polynesians. Constructs with FUT1 and FUT2 wild type genes, and the FUT2Se wA385T,se G428A andse C571T mutated alleles, were cloned into pcDNAI, and expressed in COS-7 cells. COS-7 cells transfected with theSe wA385T allele had weak, but detectable, (1,2)fucosyltransferase activity, with an acceptor substrate pattern similar to the wild type FUT2 gene. Comparative kinetic studies from cell extracts with mutatedSe wA385T and wild type FUT2 alleles gave similarK m values, but less enzyme activity was present in cells transfected withSe wA385T (V max 230 pmol h–1 mg–1), as compared to those transfected with FUT2 (V max 1030 pmol h–1 mg–1), suggesting that the mutated enzyme is more unstable. These results confirm that the molecular basis for the erythrocyte Le(a+b+) and the associated ABH salivary partial-secretor phenotype, is an amino acid change of Ile 129Phe in the secretor (1,2)fucosyltransferase.Abbreviations (1,3/1,4)fucosyltransferase GDP-L-fucose:-D-N-acetylglucosaminide 3/4--L-fucosyltransferase - (1,2)fucosyltransferase GDP-L-fucose: -D-galactoside-2--L-fucosyltransferase - bp base pairs - FUT1 H gene; FUT2,Se gene - FUT3 Lewis gene or Fuc-TIll gene - FUT4 Fuc-TIV gene - FUT5 Fuc-TV gene - FUT6 Fuc-TVI gene - MAb monoclonal antibody - PCR polymerase chain reaction - RFLP restriction fragment length polymorphism - se G428A FUT2 nonsecretor GA mutation at nucleotide 428 - se C571T FUT2 nonsecretor CT mutation at nucleotide 571 - Se wA385T FUT2 secretor weak AT mutation at nucleotide 385 - SSP sequence specific primer  相似文献   

3.
Red cell antigen, serum protein and red cell enzyme groups were determined for a series of 1,821 individuals belonging to six language families in Western New Guinea. Three of the language families represent groupings of languages spoken by people in the swampy coastal plain of south central Western New Guinea, two belong to the Central Highlands and one to the Lake Plain area near the confluence of the Idenburg and Rouffaer Rivers. The distribution of genetic markers reveals similarities with other parts of New Guinea. The A2 allele is absent in the ABO system, the frequency of Ns in the MNS system is very high as is the R1 (CDe) allele in the Rh system. Hp1 frequencies are high, and the transferrin allele TfD 1 is present as in other parts of New Guinea. In the red cell enzyme systems several alleles were detected which are characteristic of Papuan, and in some cases other Melanesian populations: these include MDH3, PGK4, PGK2, PGM92, PGM102, as well as some very restricted alleles such as Peptidase B6 and Pep B2. Three indices of genetic distance were computed. The most striking results are the genetic closeness of the Dani and Moni populations from the Central Highlands to the Asmat on the southern coastal plain, and the relative remoteness of the Awyu from the other south coastal populations. The results are discussed in terms of recent theories on the origin and dispersal of Papuan languages.  相似文献   

4.
Anthropometric measurements and measurements of resting metabolism were made on 15 young male highlanders in Beha village at altitudes between 1,500 m and 1,800 m in the Eastern Highland of Papua New Guinea in August in 1978 and 10 young male Japanese in Nishinomiya in September. New Guineans showed significantly lower height, considerably lower body weight than Japanese but heavier body weight for height and significantly greater mean values of Rohrer's index and Brugsch's index than Japanese. Skinfold thicknesses for New Guineans were significantly smaller than those for Japanese. Thus, physically, New Guineans were more muscular and athletic when compared with Japanese. The mean value of resting metabolic rate for New Guineans, 46.35 W/m2, at 25°C was considerably lower than that for Japanese, 51.01 W/m2. New Guineans showed significantly lower mean value of resting metabolism 47.57 W/m2 at 30°C than Japanese 55.16 W/m2. The mean values of respiratory quotient for New Guineans (RQ = 0.950 at 25°C and 0.971 at 30°C) were significantly greater than those for Japanese (0.81 at 25°C and 0.81 at 30°C). New Guineans showed considerably lower mean value of heart rate at 30°C (71.1 beats/min) than Japanese (79.2 beats/min). The smaller physique of New Guineans might be the result of lower caloric intake and protein intake as well as of living in a tropical climate.  相似文献   

5.
We have analyzed the allele frequency distribution at the highly polymorphic variable number of tandem repeat (VNTR) locus D1S80 (pMCT118) in seven ethnic populations (namely, New Guinea Highlanders of Papua New Guinea, Dogrib Indians of Canada, Pehuenche Indians of Chile, American and Western Samoans, Kacharis of Northeast India, and German Caucasians) using the polymerase chain reaction (PCR) technique. In the pooled sample of 443 unrelated individuals 20 segregating alleles were detected. A trimodal pattern of allelic distribution is present in the majority of populations and is indicative of the evolutionary antiquity of the polymorphism at this locus. In spite of the observed high degree of polymorphism (expected heterozygosity 56%–86%), with a single exception — the marginally significant P value (0.04) of the exact test in American Samoans — the genotype distributions in all populations conform to their respective Hardy-Weinberg expectations. Summary statistics indicate that, in general, the allele frequency distribution at this locus may be approximated by the infinite allele model. The data also demonstrate that alleles that are shared by all populations have the highest average frequency within populations. Furthermore, the kinship bioassay analysis demonstrates that the extensive variation observed at the D1S80 locus is at the interindividual within population level, which dwarfs any interpopulation allele frequency variation, consistent with the population dynamics of hypervariable polymorphisms. These characteristics of the D1S80 locus make it a very useful marker for population genetic research, genetic linkage studies, forensic identification of individuals, and for determination of biological relatedness of individuals.  相似文献   

6.
Gammaglobulin groups (Gm and Inv) of various Southern African populations   总被引:9,自引:0,他引:9  
Data are presented on the distribution of the Gm and Inv groups in approximately 3500 individuals belonging to a number of diverse Southern African populations. The indigenous peoples show the presence of the Gm alleles known to occur in Negroes (Gm1, 5, 13, 14, Gm1, 5, 6, 14 and Gm1, 5, 6) but the Bushmen possess some of them in very low frequencies and have, in addition and in appreciable frequencies the Gm1 and Gm1, 13 alleles which have not been reported as occurring in West African populations. The distribution of the Gm1, 13 allele in various Bantu-speaking tribes of the sub-continent reveals a marked cline, increasing from north to south along the eastern seaboard. The correlation between the frequency of Gm1, 13 and the Khoisan morphological, features present in a number of the tribes, and with the linguistic evidence which has been used to group them is high. The Bushmen possess a Gm1, 5 allele and may also have a Gm1, 5, 13, 14, 17, 21 allele. A Gm1, 2, 5, 13, 14, 17 allele seems to be present in the Bantu. Its presence in Eastern New Guinea would also appear to be indicated by the population data presented here.  相似文献   

7.
B. Wallace 《Genetica》1982,58(2):141-151
Sepia-eyed flies carrying the slow electrophoretic variant of either Est-6 or Adh were introduced in low numbers and at infrequent intervals into populations of wildtype flies (+ se /+ se ) that were also homozygous for the fast moving variant of either Est-6 (50 populations) or Adh (50 populations). After 24 generations, the frequency of the sepia alleles was approximately 25%, although there was considerable variation from population to population. The fate of the Est-6 slow allele corresponded closely to that of sepia (which is located ten map units distant), although one population retained the slow allozyme variant but rejected sepia. The Adh slow allele was also retained by many populations. A number of them retained Adh-S but not sepia, and vice versa; these loci are on different chromosomes. The advantage of sepia heterozygotes was estimated to be about twice that of wildtype homozygotes. The data suggest that the selective advantage resides not with the sepia locus itself, but with a nearby chromosomal region.Financial support for work reported here was supplied under grant number GM24850, National Institutes of Health.  相似文献   

8.
Pgm allele frequencies of 383 individuals were determined in a sample ofDrosophila melanogaster from three laboratory Sardinian populations, using the techniques of standard electrophoresis, heat denaturation, and isoelectric focusing. The analysis of the progeny obtained from informative crosses showed that the isoelectric focusing patterns segregate in a Mendelian way. ThePgm 1.00 andPgm 0.70 electrophoretic alleles displayed different isoelectric points, whereas thePgm 1.00,tr andPgm 1.00,ts isoelectrophoretic alleles could not be differentiated when tested by isoelectric focusing. Moreover, thePgm 0.70,ts allele was split into two classes, with isoelectric points ofpH 6.4 andpH 6.6.  相似文献   

9.
In human populations, a null allele having several nucleotide differences from the wild-type allele is segregating at the FUT2 locus (the ABO-Secretor locus) encoding α(1,2)fucosyltransferase. To estimate the age of the most recent common ancestor (MRCA) of these two alleles, we sequenced FUT2 homologues from chimpanzee, gorilla, orangutan, and green monkey. Since we did not detect acceleration or any heterogeneity in the substitution rate at this locus among these species, the age of the MRCA was estimated to be around 3 MYA, assuming the divergence time of human and chimpanzee to be 5 MYA. We developed a simple test to examine whether or not the old age of the MRCA of the FUT2 is consistent with that expected for two divergent neutral alleles sampled from a random mating population. An application of the test to the data at FUT2 indicated that the age of the MRCA is too old to be explained by the simple neutral assumptions, although our test depends on accurate estimation of the divergence time of human and chimpanzee in units of twice the human population size. Various possibilities including balancing selection are discussed to explain this old age of the MRCA. Received: 9 May 1999 / Accepted: 20 September 1999  相似文献   

10.
The aim of this paper is to accurately identify a case of B para-Bombay and to analyze the genetic mutation. ABO and Lewis blood groups were identified by standard serological methods, and trace antigens on RBCs were detected by adsorption-elution test, while blood group substances in the saliva were detected by agglutination inhibition test. The ABO gene exons 6-7, FUT1 gene exon 4 and FUT2 gene exon 2 were directly sequenced. Serological results showed that there were B antigens on RBCs without H antigens, anti-A and anti-HI antibodies in serum, and B and H blood group substances in the saliva. The Lewis phenotype was Le (a-b+). According to gene sequencing analysis, ABO, FUT1 and FUT2 genotypes were B101/O02, h328G/Ah328G/A and Se357C/TSe357C/T, respectively. This rare phenotype can be mislabeled as "O" if any of the detailed investigations are not performed. Therefore, in order to ensure the safety of blood transfusion, genetic and serological tests are necessary for the correct identification of difficult blood groups.  相似文献   

11.
The aim of this paper is to accurately identify a case of B para-Bombay and to analyze the genetic mutation. ABO and Lewis blood groups were identified by standard serological methods, and trace antigens on RBCs were detected by adsorption-elution test, while blood group substances in the saliva were detected by agglutination inhibition test. The ABO gene exons 6-7, FUT1 gene exon 4 and FUT2 gene exon 2 were directly sequenced. Serological results showed that there were B antigens on RBCs without H antigens, anti-A and anti-HI antibodies in serum, and B and H blood group substances in the saliva. The Lewis phenotype was Le (a-b+). According to gene sequencing analysis, ABO, FUT1 and FUT2 genotypes were B101/O02, h328G/Ah328G/A and Se357C/TSe357C/T, respectively. This rare phenotype can be mislabeled as "O" if any of the detailed investigations are not performed. Therefore, in order to ensure the safety of blood transfusion, genetic and serological tests are necessary for the correct identification of difficult blood groups.  相似文献   

12.
13.
Distribution of ADH2 and ALDH2 genotypes in different populations   总被引:19,自引:0,他引:19  
Summary The distribution of the human liver alcohol dehydrogenase, ADH2, and aldehyde dehydrogenase, ALDH2, genotypes in 21 different populations comprising Mongoloids, Caucasoids, and Negroids was determined by hybridization of the amplified genomic DNA with allele-specific oligonucleotide probes. Whereas the frequency of the ADH 1 2 allele was found to be relatively high in the Caucasoids, Mexican Mestizos, Brazilian Indios, Swedish Lapps, Papua New Guineans and Negroids, the frequency of the ADH 2 2 gene was considerably higher in the Mongoloids and Australian Aborigines. The atypical ALDH2 gene (ALDH22) was found to be extremely rare in Caucasoids, Negroids, Papua New Guineans, Australian Aborigines and Aurocanians (South Chile). In contrast, this mutant gene was found to be widely prevalent among the Mongoloids. Individuals possessing the abnormal ALDH2 gene show alcohol-related sensitivity responses (e.g. facial flushing), have the tendency not to be habitual drinkers, and apparently suffer less from alcoholism and alcohol-related liver disease.  相似文献   

14.
C. Náiera  J. L. Ménsua 《Genetica》1988,77(2):123-131
In previous work analyzing variability of eye colour alleles existing in natural populations of D melanogaster, it was observed that the number of females heterozygous for some eye colour alleles was greater in a wine cellar population than in populations outside this cellar. In order to determine which mechanisms caused these eye colour alleles to be favored in the heterozygotes, the changes in the frequency of four eye colour alleles frequently seen in the cellar population (se77o, sf77m, cd77o and multichromosomal 77o) was studied in artificial populations. Two different culture media, one supplemented with 10% ethanol and the other without ethanol were used. It was found that each of the four mutants reached similar equilibrium frequencies in both media, though the safranin allele (sf77m) equilibrium frequency was significantly higher in the alcohol medium. A significant excess of heterozygotes were also observed in these populations.  相似文献   

15.
16.
Summary A C7 cDNA probe detecting a TaqI restriction fragment length polymorphism has been used to examine the segregation of the silent allele (C7*Q0) in two familial deficiencies. Carrier diagnosis in healthy children is possible when both parents are heterozygotes. Only one of these two families was informative. The silent allele is linked to different TaqI alleles in both families. This suggests that at least two different C7*Q0 alleles are present in our population. This paper gives a protocol for genetic studies of hereditary traits in which the C7 gene and other genes tightly linked to it are involved.  相似文献   

17.
To investigate the paternal population history of New Guinea, 183 individuals from 11 regional populations of West New Guinea (WNG) and 131 individuals from Papua New Guinea (PNG) were analyzed at 26 binary markers and seven short-tandem-repeat loci from the nonrecombining part of the human Y chromosome and were compared with 14 populations of eastern and southeastern Asia, Polynesia, and Australia. Y-chromosomal diversity was low in WNG compared with PNG and with most other populations from Asia/Oceania; a single haplogroup (M-M4) accounts for 75% of WNG Y chromosomes, and many WNG populations have just one Y haplogroup. Four Y-chromosomal lineages (haplogroups M-M4, C-M208, C-M38, and K-M230) account for 94% of WNG Y chromosomes and 78% of all Melanesian Y chromosomes and were identified to have most likely arisen in Melanesia. Haplogroup C-M208, which in WNG is restricted to the Dani and Lani, two linguistically closely related populations from the central and western highlands of WNG, was identified as the major Polynesian Y-chromosome lineage. A network analysis of associated Y-chromosomal short-tandem-repeat haplotypes suggests two distinct population expansions involving C-M208--one in New Guinea and one in Polynesia. The observed low levels of Y-chromosome diversity in WNG contrast with high levels of mtDNA diversity reported for the same populations. This most likely reflects extreme patrilocality and/or biased male reproductive success (polygyny). Our data further provide evidence for primarily female-mediated gene flow within the highlands of New Guinea but primarily male-mediated gene flow between highland and lowland/coastal regions.  相似文献   

18.
We have analyzed the allele frequency distribution at the hypervariable locus 3' to the apolipoprotein B gene (ApoB 3' VNTR) in five well-defined human populations (Kacharis of northeast India, New Guinea Highlanders of Papua New Guinea, Dogrib Indians of Canada, Pehuenche Indians of Chile, and a relatively homogeneous Caucasian population of northern German extraction) by using the PCR technique. A total of 12 segregating alleles were detected in the pooled sample of 319 individuals. A fairly consistent bimodal pattern of allele frequency distribution, apparent in most of these geographically and genetically diverse populations, suggests that the ApoB 3' VNTR polymorphism predates the geographic dispersal of ancestral human populations. In spite of the observed high degree of polymorphism at this locus (expected heterozygosity levels 55%-78%), the genotype distributions in all populations (irrespective of their tribal or cosmopolitan nature) conform to their respective Hardy-Weinberg predictions. Furthermore, analysis of the congruence between expected heterozygosity and the observed number of alleles reveals that, in general, the allele frequency distributions at this locus are in agreement with the predictions of the classical mutation-drift models. The data also show that alleles that are shared by all populations have the highest average frequency within populations. These findings demonstrate the potential utility of highly informative hypervariable loci such as the ApoB 3' VNTR locus in population genetic research, as well as in forensic medicine and determination of biological relatedness of individuals.  相似文献   

19.
Five novel missense mutations, viz., C304 A, T370 G, G484 A, G667 A, and G808 A, in the Lewis gene (FUT3) were detected in African (Xhosa) and Caucasian individuals in South Africa. These single base substitutions may result in changes in amino acid residues from Gln102 to Lys in the 304 mutation, Ser124 to Ala in the 370 mutation, Asp162 to Asn in the 484 mutation, Gly223 to Arg in the 667 mutation, and Val270 to Met in the 808 mutation. Out of the five novel mutations identified in this investigation, four new alleles (le 484,667 , le 484,667,808 , Le 304 , and Le 370 ) were determined in the Xhosa population and two new alleles (le 202,314,484 and Le 304 ) in the Caucasian population. The determination of α(1,3/1,4)fucosyltransferase activity, after transfection of plasmids containing the new alleles into COS7 cells, suggested that alleles le 484,667 and le 484,667,808 encoded an inactive enzyme, and that alleles Le 304 and Le 370 encoded a functional enzyme. In addition, we also examined the incidence of five common alleles, Le 59 , le 59,508 , le 59,1067 , le 202,314 , and le 1067 in two populations by the polymerase chain reaction/restriction fragment length polymorphism method and compared differences in the allele frequencies of FUT3 among three ethnic groups (Orientals, Africans, and Caucasians). Received: 19 January 1998 / Accepted: 4 Febraury 1998  相似文献   

20.
The distribution of the three previously reported alleles, with normal products at the factor XIII A subunit structural locus, FXIIIA*1, FXIIIA*2 and FXIIIA*4 has been studied in populations from the region extending from the Indonesian archipelago through Papua New Guinea, Australia and New Zealand to the Pacific Islands of Micronesia, Melanesia and Polynesia. In addition a population from the Caspian Littoral of Iran and a population of South American Indians were studied. The FXIIIA*1 and FXIIIA*2 alleles were polymorphic in all populations studied. The distribution of the FXIIIA*4 allele suggests that it may be a Melanesian marker.  相似文献   

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