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1.
Until recently, the Waorani Indians of Ecuador's Amazon headwaters maintained a fierce resistance to all intruders into their territory, and as a result of their actions and reputations a population of 600 people controlled a very large territory (about 8,000 square miles). The isolation of the Waorani has resulted in a large linguistic and genetic distance from their neighbors. Our survey of red cell enzymes, immunoglobulin allotypes, and dermatoglyphics demonstrates that the Waorani are a highly inbred and homogeneous population. Of 18 red cell enzymes studied, the Waorani have a limited polymorphism for only 6. Only two Gm haplotypes (Gm1,2,17,21, Gm1,17,21) were found and 60% of those tested were homozygous for the Gm1,17,21 haplotype. All individuals were A2m (1) and 95% of these were homozygous. The Waorani's dermatoglyphic traits fell within the wide range found among other South American Indians with close affinity to the Ecuadorian Jivaro group. Despite the limitations of these genetic systems, they demonstrate that the Waorani share limited genetic traits with the neighboring Jivaro Indians and are isolated from other tribal populations in South America.  相似文献   

2.
Since the discovery of Gm ab3st haplotype which characterizes Mongoloid populations in 1966, the distribution of the genetic markers of immunoglobulins (Gm) among the Mongoloid populations scattered from Southeast Asia through East Asia to South America has been investigated and concluded as follows: 1) Mongoloid populations characterized by the four Gm haplotypes, ag, axg, ab3st and afb 1b3 are divided into two groups on the basis of analysis of genetic distances based on the Gm haplotype frequencies: one is a southern group characterized by a remarkably high frequency of Gm afb 1b3 and a low frequency of Gm ag and the other is a northern group characterized by a high frequency of Gm a and an extremely low frequency of Gm afb 1b3. 2) Populations in China, mainly Han including minority nationalities, show remarkable heterogeneities from north to south, in sharp contrast to Korean and Japanese populations showing homogeneities, respectively. The center of dispersion of the Gm afb 1b3 characterizing southern Mongoloids must exist in Guangxi and Yunnan area in the southwest China. 3) The Gm ab3st gene found in the highest incidence among the north Baikal Buriats flows in all directions. The gene, however, shows precipitous drop which occur from mainland China to Southeast Asia and from North to South-America, although the Gm ab3st gene is still found in high incidences among Eskimos, Yakuts, Tibetans, Olunchuns, Koreans, Japanese and Ainus. On the other hand, the gene is introduced into Huis, Uighurs, Indians, Iranians and far Hungarians.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Summary Since the discovery in 1966 of the Gm ab3st gene, which characterizes Mongoloid populations, the distribution of allotypes of immunoglobulins (Gm) among Mongoloid populations scattered from Southeast Asia through East Asia to South America has been investigated, and the following conclusions can be drawn: 1. Mongoloid populations can be characterized by four Gm haplotypes, Gm ag, axg, ab3st, and afb1b3, and can be divided into two groups based on the analysis of genetic distances utilizing Gm haplotype frequency distributions: the first is a southern group characterized by a remarkably high frequency of Gm afb1b3 and a low frequency of Gm ag, and the second, a northern group characterized by a high frequency of both Gm ag and Gm ab3st but an extremely low frequency of Gm afb1b3. 2. Populations in China, mainly Han but including minority nationalities, show remarkable heterogeneity of Gm allotypes from north to south and contrast sharply to Korean and Japanese populations, which are considerably more homogenous with respect to these genetic markers. The center of dispersion of the Gm afb1b3 gene characterizing southern Mongoloids has been identified as the Guangxi and Yunnan area in the southwest of China. 3. The Gm ab3st gene, which is found with its the highest incidence among the northern Baikal Buriats, flows in all directions. However, this gene shows a precipitous drop from mainland China to Taiwan and Southeast Asia and from North to South America, although it is still found in high frequency among Eskimos, Koryaks, Yakuts, Tibetans, Olunchuns, Tungus, Koreans, Japanese, and Ainus. On the other hand, the gene was introduced into Huis, Uyghurs, Indians, Iranians, and spread as far as to include Hungarians and Sardinians in Italy. On the basis of these results, it is concluded that the Japanese race belongs to northern Mongoloids and that the origin of the Japanese race was in Siberia, and most likely in the Baikal area of the Soviet Union.  相似文献   

4.
A review is made of the Gm haplotype distribution in 60 groups of Eskimos, North, Central and South American Indians, totaling 22,808 individuals. Differences were observed in the shapes of the distribution of Gm*ag and the other markers. Nearly identical values for FST and average heterozygosities were obtained in the North+Central/South comparisons. North-South and Southwest/Northeast clinal differences were observed in the Americas using correspondence factorial analysis. The two haplotypes mainly responsible for these differences are Gm*axg and Gm*abOst. When the populations are classified by language groups, besides the recognized differences between Eskimos and Athabaskan (Na-Dene) speakers compared with Amerinds, others are found. For instance, Uto-Aztecan speakers of the United States and Mexico differ in Gm frequencies from the Nuclear Chibchan, Macro-Arawak, and Carib speakers of Central and South America. The notion of a homogeneous Amerind genetic pool does not conform with these and other results. © 1993 Wiley-Liss, Inc.  相似文献   

5.
Serum samples from 226 Gypsies were tested for Gm(1,2,4,5,8,10,11,14,17,21,23,25) and for Inv(1,2). The Gm phenotypes found are very numerous and the more frequent among this population are: Gm(4,5, 8,10,11,14,17,23,25) and Gm(1,2,4,5,8,10,11,14,17,21,23,25). All the phenotypes except three can be explained by nine haplotypes: Gm4,5,8,10,11,14,23,25, Gm1,4,5,8,10,11,14,23,25, Gm4,5,8,10,11,14,25, Gm1,17,21, Gm1,10,11,17,25, Gm1,2,17,21, Gm1,8,17,21, Gm1,8,17,21,23 and Gm1,5,10,11,14,17. The haplotypes Gm1,17,21, Gm1,2,17,21, Gm4,5,8,10,11,14,25 (with or without Gm[ 3]) are all three common among Caucasoids, Gm1,4,5,10,11,14,23,25 (common among Mongoloids) and Gm1,5,10,11,14,17 (common to Negroids). For the Inv system, this population possesses a very low frequency of Inv(1) and Inv(2).  相似文献   

6.
We report the results of typings, for immunoglobulin G allotypes, of 5392 Native Americans from ten samples, the typings having been performed over the last 20 years. Four cultural groups are represented: the Pimans-Pima and Papago; the Puebloans-Zuni and Hopi; the Pai-Walapai; and the Athabascans-Apache and Navajo. The haplotype Gm1;21 has the highest frequency in each population while Gm1,2;21 is polymorphic in all except the Hopi. The Mongoloid marker Gm1;11,13 is found primarily in the Athabascans. The Caucasian haplotype Gm3;5,11,13 is found at polymorphic frequencies in several of the populations but its frequency is very low or absent among nonadmixed individuals. Although Nei's standard genetic distance analysis demonstrates genetic similarity at the Gm and Km loci, the heterogeneity that does exist is consistent both with what is known about the prehistory of Native Americans and traditional cultural categories. When the current Gm distributions are analyzed with respect to the three-migration hypothesis, there are three distinct Gm distributions for the postulated migrants: Gm1;21 and Gm1,2;21 for the Paleo-Indians 16,000 to 40,000 years ago; Gm1;21, Gm1,2;21, and Gm1;11,13 for the second wave of Na-Dene hunters 12,000 to 14,000 years ago; and Gm1;21 and Gm1;11,13 for the Eskimo-Aleut migration 9,000 years ago. The Pimans, Puebloans, and the Pai are descendents of the Paleo-Indians while the Apache and Navajo are the contemporary populations related to the Na-Dene. Finally, the Gm distribution in Amerindians is found to be consistent with a hypothesis of one migration of Paleo-Indians to South American, while the most likely homeland for the three ancestral populations is found to be in northeastern Asia.  相似文献   

7.
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10.
The Gm and Inv types were determined for eight San (Bushman) populations, two Khoikhoi (Hottentot) populations, one Coloured population, 112 San families in which the genotypes of the parents could be unambiguously determined, and for 65 San families in which the genotype of one or both parents could not be determined with certainty. The population and family data establish that the haplotype array of the San is composed of Gm1,21, Gm1,13, Gm1,5,13,14, and Gm1,5,13,14,21; Gm1,5,6 and Gm1,5,6,14 are also present but may have been acquired through admixture with Negroes. The Gm1,5,13,14,21 haplotype has not been found to be polymorphic in any other population. The haplotype array of the Khoikhoi is composed of Gm1,2,21, Gm1,13, and Gm1,5,13,14; Gm1,5,6 and Gm1,5,6,14 are also present but, as in the case of the San, may be due to admixture. The San and Khoikhoi differ from each other in that the former have the Gm1,21 and Gm1,5,13,14,21 haplotypes not present in the latter, and the Khoikhoi have the Gm1,2,21 haplotype not present in the San. These three haplotypes and Gm1,13 serve to distinguish the Khoisan people from other African peoples.  相似文献   

11.
Gm typing on the serum specimens of 507 Ashkenazic Jews (pre-dominantly of Polish-Russian ancestry) from Toronto, Canada has established the presence of haplotypes Gm3;5, Gm1;21, Gm1,2;21, and Gm1,17;5, and the absence of haplotypes Gm1;13,15,16, Gm1;5,6, and Gm1;5,6,24 which have been found in other Jewish peoples. It is suggested that Ashkenazic populations have lower frequencies of haplotype Gm1,17;5 than non-European Jewish populations, and that some eastern European Jewish populations have acquired the Gm1;13,15,16 haplotype through gene flow from Central Asia. Thus Jewish populations show differences in the Gm system; many of the differences may be in the direction of similarities to neighbouring non-Jewish populations.  相似文献   

12.
A radioimmunoassay for the human allotype Gm(b0) which provides a sensitive and quantitative measurement of the level of this IgG3 genetic marker has been developed. The assay system can detect 15 nanograms of Gm(b0) IgG3 protein and is not inhibited by immunoglobulins of other allotypes and isotypes. Using this assay, good correlation was found between IgG3 and Gm(b0) levels in homozygous Gm(f, b0) sera and gene dosage effects could be confirmed. The correlation between Gm(b0) levels and IgG3 in Negroid Gm(a, b0) sera was not as good. This reduced correlation has been attributed to antigen differences in the IgG3 Gm markers characteristic of some Negroid Gm(a, b0) sera.  相似文献   

13.
14.
R. H. Ward  James V. Neel 《Genetics》1976,82(1):103-121
The Yanomama Indians are a South American tribe distributed over an irregular area approximately 200 x 300 miles. The gene frequencies observed at 12 loci in 47 villages within this area have been analyzed for the occurrence of clines. Apparently significant clines are observed for alleles of the Rh, MNSs, Kidd, Gm, Inv and serum albumin system. Available data concerning recent tribal expansion and admixture permit a tentative analysis of the causes of these clines. Although the action of selection cannot be rigorously excluded, it seems unlikely to be the major cause. Admixture with surrounding tribes plays a role which can be quantified because of the fortuitous circumstance of two genetic markers for admixture. It is suggested that an important factor in the origin of these clines is the manner in which the tribe has recently expanded through successive village fissionings and a predominantly centrifugal pattern of village migration.  相似文献   

15.
In a sample of 4,920 Native Americans of the Pima and Papago tribes, there is a very strong negative association between the Gm haplotype Gm3;5,13,14 and type 2--or non-insulin-dependent--diabetes mellitus (prevalence ratio = 0.27, 95% confidence interval 0.18-0.40). One might conclude from this observation that the absence of this haplotype--or the presence of a closely linked gene--is a causal risk factor for the disease. It is shown that Gm3;5,13,14 is a marker for Caucasian admixture, and it is most likely the presence of Caucasian alleles and the concomitant decrease of Indian alleles that lowers the risk for diabetes, rather than the direct action of the haplotype or of a closely linked locus. This study demonstrates both the potential confounding effect of admixture on the interpretation of disease association studies and the importance of considering genetic admixture (or excluding individuals with genetic admixture) in studies of genetic markers of disease. The relationship between this admixture marker and the prevalence of diabetes also suggests a strong genetic component in the susceptibility to type 2 diabetes in Pima and Papago Indians.  相似文献   

16.
调查了我国24个民族、74个群体的免疫球蛋白同种异型Gm、Km分布。测定了9560例个体的Gm(1,2,3,5,21)因子和9611例个体的Km(1)因子。根据Gm单体型频率计算了遗传距离并绘制了系统树。结果支持作者早前提出的有关中华民族起源于古代两个不同群体的假说。这两个群体大致以北纬30度为界,分别居栖在黄河和长江流域。本文数据和其他主要人种的Gm分布资料相比较,作者认为在人类进化中,尼格鲁人种首先和高加索-蒙古人种分离;然后高加索人种和蒙古人种分离。不同人种间的差异,大于同一人种内不同群体间的差异。蒙古人种明显地被分为南、北两大类型,分别以具有高频率的Gm~(1;21)和Gm~(1,3;5)单体型作为种族的标记。与高加索人种关联的Gm~(3;5)单体型存在于中国西北地区的少数民族中,提示混有高加索人种血缘。很可能来源于中亚地区的高加索人,通过“丝绸之路”进入中国。Km因子在所调查的74个群体中呈随机分布。  相似文献   

17.
We have identified an AFLP marker SA598 that is linked to Gm7, a gene conferring resistance to biotypes 1, 2 and 4 of the gall midge ( Orseolia oryzae), a major dipteran pest of rice. A set of PCR primers specific to an RFLP marker, previously identified to be linked to another gall midge resistance gene Gm2, also amplified a 1.5-kb (F8LB) fragment that is linked to Gm7. Gm7 is a dominant gene and non-allelic to Gm2. Hybridization experiments with clones from a YAC library of Nipponbare, a japonica variety, a BAC library of IR-BB21, an indica variety, and cosmid clones encompassing Gm2 from Phalguna, an indica variety, with F8LB and SA598 as probes, revealed that Gm7 is tightly linked to Gm2 and is located on chromosome 4 of rice. SA598 was sequenced and the sequence information was used to design sequence-characterized amplified region (SCAR) primers. The potential use of these SCAR primers in marker-aided selection of Gm7 in a rice breeding program has been demonstrated.  相似文献   

18.
Long non-coding RNAs (lncRNAs) have been found to participate in the regulation of human spermatogenic cell development. However, little is known about the abnormal expression of lncRNAs associated with spermatogenic failure and their molecular mechanisms. Using lncRNA microarray of testicular tissue for male infertility and bioinformatics methods, we identified the relatively conserved lncRNA Gm2044 which may play important roles in non-obstructive azoospermia. The UCSC Genome Browser showed that lncRNA Gm2044 is the miR-202 host gene. This study revealed that lncRNA Gm2044 and miR-202 were significantly increased in non-obstructive azoospermia of spermatogonial arrest. The mRNA and protein levels of Rbfox2, a known direct target gene of miR-202, were regulated by lncRNA Gm2044. Furthermore, the miR-202-Rbfox2 signalling pathway was shown to mediate the suppressive effects of lncRNA Gm2044 on the proliferation of human testicular embryonic carcinoma cells. Understanding of the molecular signalling pathways for lncRNA-regulated spermatogenesis will provide new clues into the pathogenesis and treatment of patients with male infertility.  相似文献   

19.
Salivary proline-rich protein (PRP) polymorphism, PRH1, PRH2, Ps, Pm (PmF), PmS and Gl, were investigated in three ethnic groups in Singapore: Chinese, Malays and Indians. The phenotype and gene frequencies were presented and comparison with other ethnic groups was made. The As protein, which was recently found in Japanese but not in Caucasians as a new allelic product of the PRH1 locus, was also observed in Chinese and Malays but not in Indians. Another allelic product (Ps4) of Ps protein polymorphism was found in Malays but not in Chinese and Indians. The results indicate the usefulness of salivary PRP polymorphism as markers in population genetic studies.  相似文献   

20.
MICA polymorphism in South American Indians   总被引:3,自引:0,他引:3  
We have studied the MICA alleles of 196 unrelated subjects from three South American Indian tribes (Toba, Wichi and Terena). They are members of isolated tribes located in the Gran Chaco area in northeastern Argentina and in Mato Grosso do Sul in South Central Brazil. Of 55 previously known alleles, nine were observed in South American Indians, compared with 16 that were found in North American Caucasians, suggesting a more restricted allelic distribution of MICA in these tribes. In South American Indians, MICA*00201 was the most frequent allele, with a gene frequency of 33% in Toba, 47% in Wichi and 44% in Terena. MICA*00201, MICA*027 (external domain sequence like MICA*008/TM allele A5) and MICA*010 accounted for more than 90% of all the MICA genes in South American Indians. In North American Caucasians, MICA*00801 (*008/A5.1) accounted for 42% of the genes and was the most common allele. We observed a high degree of linkage disequilibrium between certain alleles of MICA and of HLA-B in the South American Indian populations. Phylogenetic trees constructed using gene frequencies of the transmembrane short tandem repeats in the populations reported here, and in other populations taken from published reports, suggest that South American Indians are more closely related to Asians than to Europeans.  相似文献   

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