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1.
A mathematical relationship between total ridge count (TRC) and pattern intensity index (PII) is explored using data from a sample of 180 males and 213 females of Negroid origin from southwestern Haiti, West Indies. Linear regression of total ridge count on pattern intensity index gave good fit to data in males. In females the linear and quadratic regression models were less satisfactory probably due to the considerable overlap of ridge count distribution between loops and whorls. Two other measures which compare better than total ridge count are absolute ridge count and weighted total ridge count. Predictions of TRC from PII on the basis of regression estimates from Haitian data gave satisfactory results for Negroid and some Caucasoid populations but less satisfactory results for Mongoloid groups suggesting that the relationship might be different in different ethnic groups.  相似文献   

2.
It is now generally accepted that Polynesia was first settled by peoples from southeast Asia. An alternative that eastern parts of Polynesia were first inhabited by Amerindians has found little support. There are, however, many indications of a 'prehistoric' (i.e. before Polynesia was discovered by Europeans) contact between Polynesia and the Americas, but genetic evidence of a prehistoric Amerindian contribution to the Polynesian gene pool has been lacking. We recently carried out genomic HLA (human leucocyte antigen) typing as well as typing for mitochondrial DNA (mtDNA) and Y chromosome markers of blood samples collected in 1971 and 2008 from reputedly non-admixed Easter Islanders. All individuals carried HLA alleles and mtDNA types previously found in Polynesia, and most of the males carried Y chromosome markers of Polynesian origin (a few had European Y chromosome markers), further supporting an initial Polynesian population on Easter Island. The HLA investigations revealed, however, that some individuals also carried HLA alleles which have previously almost only been found in Amerindians. We could trace the introduction of these Amerindian alleles to before the Peruvian slave trades, i.e. before the 1860s, and provide suggestive evidence that they were introduced already in prehistoric time. Our results demonstrate an early Amerindian contribution to the Polynesian gene pool on Easter Island, and illustrate the usefulness of typing for immunogenetic markers such as HLA to complement mtDNA and Y chromosome analyses in anthropological investigations.  相似文献   

3.
The total ridge count (TRC) was viewed as a common composite trait with definite correlations between its components — the ridge counts (RC) of individual fingers. The TRC variability was accordingly examined as a function of the variability of these components. The distribution of pattern types on the fingers, the RC of patterns per total as well as per finger location, and the mean finger RC were all analyzed in relation to the RC variability and to a newly described phenomenon — the mutual influence on the RC variability of different patterns present concomitantly in an individual. It was concluded that the TRC variability is conditioned by the frequencies of the same genes which are responsible for the presence of the different finger pattern types. A high negative correlation coefficient, −0.901, was found between the pattern intensity index (PII) and the coefficient of variation of the TRC. The linear regression equation was: CV=90.75−4.20 PII. Biological isolation and the ensuing consanguinity may affect the TRC variability of a population by modifying the frequencies of these genes. This influence may be a decreasing as well as an increasing one. In contrast, when a common metric trait which is determined by additive genes without any dominance (as the TRC is frequently believed to be) is subjects to consanguinization effects, only a decrease in the variation is expected. The dermatoglyphics of 625 Jewish males were investigated and the general character of some dermatoglyphic regularities and trends was compared with and corroborated by data from the literature.  相似文献   

4.
Isolated populations that recently have been derived from small homogeneous groups of founders should have low genetic diversity and high levels of linkage disequilibrium and should be ideal for mapping ancestral polymorphisms that influence complex genetic disease susceptibility. Populations that fulfill these criteria have been difficult to identify. We have been looking for Polynesian populations with these characteristics, because Polynesians have high rates of complex genetic diseases. In Niue Islanders all ancestral female (mitochondrial HSVI sequence) and 90.4% of ancestral male (Y-chromosome haplogroup) lineages are of Southeast Asian origin. The frequency of European Y-chromosome haplogroups is 7.2%. The diversities of mitochondrial HSV1 sequences (h = 0.18 +/- 0.05) and Y-chromosome haplo-groups (h = 0.18 +/- 0.05) are lower than values published for any other population. Ten autosomal microsatellites spaced over 5.8 cM show low allele numbers in Niue Islanders relative to Europeans (55 vs. 88 total alleles, respectively) and a modest reduction in heterozygous loci (0.71 +/- 0.02 vs. 0.78 +/- 0.02, p = 0.04). The higher linkage disequilibrium (d2) between these loci in Niue Islanders relative to Europeans (p = 0.001) is negatively correlated (r = -0.47, p = 0.01) with genetic distance. In summary, Niue Islanders are genetically isolated and have a homogeneous Southeast Asian ancestry. They have reduced autosomal genetic diversity and high levels of linkage disequilibrium that are consistent with the influence of genetic drift mechanisms, such as a founder effect or bottlenecks. High-powered linkage disequilibrium studies designed to map ancestral polymorphisms that influence complex genetic disease susceptibility may be feasible in this population.  相似文献   

5.
The palmar prints of 297 male and female Easter Islanders were analyzed according to the Penrose and Loesch topological classification system. While the frequencies of most pattern elements were not found to differ significantly between the sexes, the placement of the axial triradius was found to be highly significant (P less than 0.01). Both males and females were found to exhibit considerable bilateral asymmetry in the a-b count and in the atd angle, but there was no significant difference between the sexes in the amount of asymmetry expressed. Family data for a small subset of the sample (51 individuals) were subjected to further statistical analysis, from which significant results (P less than 0.05) were obtained both on chi-square tests for frequency of pattern elements and ANOVA tests for a-b counts, atd angle, and A-line exit. The implications of these results are considered from a developmental perspective. It is suggested that a particular pattern combination (termed a formula) could be used to represent a default value and that other formulae might then be considered as deviations from this default value. Such variation, theoretically at least, might be traced to genetic influences or to the embryological environment present during the time of dermatoglyphic formation.  相似文献   

6.
In repetitive movement patterns of everyday behaviour in humans a time constant of about 3 s could be shown to prevail. This time constant was found in four independent cultures (Europeans, Trobriand Islanders, Yanomami Indians and Kalahari Bushmen) and structures behaviour into units. As Pöppel (1978, 1985) has already found such a time constant in recited verse and optical illusions, it seems that we are dealing here with a universal central nervous mechanism structuring time. Its function could be seen in creating a subjective present and in facilitating communication and synchronisation between interactants. Only 15% of patterns in the investigated behaviour repetitions do not obey the 3-s time span. These are stereotyped behaviour patterns of longer duration which seem to have a special function.  相似文献   

7.
Among 1,605 Solomon Islanders from four tribes, there was no sex difference in relative length of the first and second toes. In three of the tribes, longer first toes were slightly more frequent in persons over the age of 45. The percentages of longer first toes in the groups as a whole were 60.5% for Baegu, 66.4% for Nasioi, and 72.1% for Kwaio. These frequencies, resembling those reported for white Americans, Europeans, and single small samples of New Caledonians and Vietnamese, were much below those for Africans. The fourth tribe, the Lau, had only 37.1% with a longer first toe, the lowest percentage reproted so far around the world. No simple mode of single-gene inheritance was apparent, and polygenic inheritance is proposed.  相似文献   

8.
Finger dermatoglyphics of the Peruvian Cashinahua   总被引:1,自引:0,他引:1  
The Peruvian Cashinahua are an isolate of unmixed American Indians living in four villages in the Southeastern part of the country. Finger dermatoglyphic data were collected from the three most closely grouped villages in the summer of 1966. The relatively low proportion of whorls and high proportion of arches, and the low values of pattern intensity (10.75) and total ridge count (89.14) contrasts markedly with other American Indian groups in general, and with Amazon Basin groups in particular. The distinctive finger print patterns may be explained by factors such as genetic drift and inbreeding, which can alter gene and phenotype frequencies in small populations.  相似文献   

9.
Microridges are F-actin-based surface protrusions of the superficial layer cells of fish epidermis. Microridge patterns progress in complexity during fish embryogenesis, often transitioning from abundant surface microvilli to the classical fingerprint arrangement. This progression suggests pattern changes may also occur during later stages of fish development. Fluorescent labelling of F-actin and morphometric analysis were therefore used to assess changes in epidermal microridge patterns in juvenile and adult sunfish (Lepomis gibbosus). The microridge patterns found in adult pumpkinseed were similar to that described for many fishes, consisting of whorls or complex multi-branched ridges. The microridge patterns of the scales from three different-sized groups of juvenile pumpkinseed were distinctly different from that of adult, however, and were present mainly as unbranched concentric or nearly concentric rings in the two larger juvenile groups. In the smallest juveniles, microridges were often apparent as fragmented ridges with abundant actin puncta. Larger juveniles sometimes displayed mixed patterns, with some microridges similar to that of both adult and juvenile patterns. The results show a transition from simple microridge patterns in juvenile pumpkinseeds to distinctly different, diverse and more complex patterns in adults. The different pattern types may reflect particular microridge functions relevant to fish size and age.  相似文献   

10.
A Bener 《Human heredity》1985,35(1):39-42
A sample of 539 Polish families and 2,500 individuals were analysed to determine whether there was any evidence of linkage between the dermatoglyphic pattern elements on fingertips and blood groups. The results of the present study did not show any indication of linkage between dermatoglyphic patterns on fingertips (ulnar loops, radial loops, whorls and arches) and the ABO, MN, Rh, Kell and Xg blood groups.  相似文献   

11.
It was stated by Birdsong and Rashad (1972) that the child of birth order number six of Korean families has significantly more true whorls on the finger tips than older brothers and sisters. To verify this assertion we studied a sample of all members of 43 normal German families with 5 or more legitimate children. The findings of the epidermal finger pattern types and those of the toe patterns were analysed. Results indicate a different conclusion regarding the number of digital whorls which were not increased statistically with increasing number of sibs. The number of whorls were randomly distributed within the heritable range of variability of the particular family. It appears of importance that, due to our analyses, the value of information of the characteristic "number of whorls" is not reduced and does not require a specific consideration regarding birth order. Furthermore, it can be stated preliminarly that there is no hint pointing to an influence of the maternal age on the number of whorls in their offspring.  相似文献   

12.
Discrete cranial morphological traits of prehistoric/protohistoric Rapa Nui (Easter Island) inhabitants have been examined and have illustrated distinct regional or tribal differences; however, craniometric traits have not been as extensively evaluated to determine if similar regional population differences exist. This study examines the range of variability of Rapa Nui craniometrics and utilizes population genetic techniques to evaluate the level of homogeneity/heterogeneity within the island populations. The data consist of 50 cranio-facial measurements of Rapanui (Easter Islanders) skeletal material from the Late Prehistoric (1680-1722) and Protohistoric (1722-1868) periods. The sample was divided into five tribal regions: North, Northeast, South, Southwest, and West. General linear models (GLM) statistical analyses revealed one variable significant for males and 10 for females across tribal regions, totaling 11 regionally significant variables. Discriminant function analyses utilizing crossvalidation provided classification error rates of 55.8% males and 59.0% for females when utilizing those eleven significant variables. Minimum F(ST) values for males (0.06378) and females (0.09409) were calculated from unbiased Mahalanobis D(2) values. These values indicate that males have greater between-group homogeneity than females. The determinant ratio for the Northeast tribal region was the only significant ratio, yet all but one of the regional determinant ratios displayed a pattern of greater male than female mobility. These results indicate that significant craniometric differences between the tribal regions did not exist in prehistoric/protohistoric Rapa Nui populations, supporting the findings of previous research which has documented the homogeneity of the craniometrics of those tribal populations. The calculated minimum F(ST) values indicate the existence of different levels of heterogeneity between the male and female Rapa Nui regional populations resulting from differential levels of migration and gene flow. This variation reflects the establishment in prehistoric times of extensive tribal marriage tumus, and the existence of lineage endogamy/restricted exogamy, not the widespread practice of strict tribal endogamy.  相似文献   

13.
Studies of gastropod shell growth at the level of fine growth layers are scarce, because coiling of gastropod shells hinders the observation of continuous growth series spanning across whorls. We propose here a new method to obtain continuous growth patterns of gastropod shells over whorls with Terebralia palustris (L.) as an example. Comparison of vertical and horizontal sections of the shell of this species reveals that growth patterns can be observed continuously for several whorls on the vertical section of the columella. In addition, an obvious tidal growth pattern preserved in this species enables us to trace its growth with a precision of 12.4 h and indicates that it takes about two years for a shell to grow from 3 cm to 9.5 cm in height and add 5 complete whorls.  相似文献   

14.
The human leukocyte antigen (HLA) distributions in 16 Pacific populations have been collated from published and unpublished reports. Gene frequency and linkage disequilibrium relationships among groups show that Australians and Papuans share a common ancestry, that coastal Melanesia has about 16% Austronesian admixture, and that Fiji is truly intermediate between Melanesia and Polynesia. In Polynesia, Cook Islanders show closer affinity with populations of Western Polynesia than with Maoris and Easter Islanders, in contrast to their linguistic affiliations, but otherwise HLA distributions show a clear division between the populations of Eastern and Western Polynesia. This study emphasizes the contribution the HLA system can make to anthropological studies and has provided a version of colonization of the Pacific compatible with theories based on prodigious efforts in many disciplines.  相似文献   

15.
Variations in asymmetry and interdigital diversity for the three finger-dermatoglyphic traits, total finger ridge count (TRC), absolute total finger ridge count (ARC), and finger pattern intensity index (PII) have been studied here from a sample of 646 males belonging to nine population groups from Maharashtra, India. It is seen that at such local level of population differentiation the ridge count measures TRC and ARC discriminate the population better as compared to PII. A considerable amount of variations also exist in their asymmetries and interdigital diversities and these suggest the possibility of their genetic controls. Such genetic controls might mediate both asymmetry and interdigital diversity jointly, as there seems to be positive correlation between these measures with respect to all the three finger-dermatoglyphic traits.  相似文献   

16.
Lipophilic persistent organic pollutants (POPs) are ubiquitous in the environment and suspected to interfere with hormone activities and reproduction. In previous studies we demonstrated that POP exposure can affect sperm DNA integrity and differences between Inuits and Europeans in sperm DNA integrity and xenobiotic activity were observed. The aim of this study was to investigate possible relations between human sperm chromatin integrity and the xenobiotic serum activity of lipophilic POPs assessed as effects on the estrogen (ER), androgen (AR), and/or aryl hydrocarbon (AhR) receptors. Human sperm chromatin integrity was assessed as DNA fragmentation index (%DFI) and high DNA stainability (%HDS) using the flow cytometric sperm chromatin structure assay (SCSA). Xenobiotic receptor activities were determined using chemically activated luciferase gene expression (CALUX) assay. The study included 53 Greenlandic Inuits and 247 Europeans (Sweden, Warsaw (Poland) and Kharkiv (Ukraine)). A heterogeneous pattern of correlations was found. For Inuits, ER and AhR activities and %DFI were inversely correlated, whereas a positive correlation between AR activity and %DFI was found for Europeans. In contrast, no correlation between receptor activities and %HDS was observed for Inuits but for Europeans positive and negative correlations were observed between ER and AR activities and %HDS, respectively. We suggest that the different patterns of xenobiotic serum activities, in combination with diet associated factors and/or genetics, might be connected to the observed differences in sperm chromatin integrity between the Inuits and Europeans.  相似文献   

17.
Analysis of the fingerprints of 571 members of the Habbanite isolate suggest inherited patterns and pattern sequences. A genetic theory has been developed; it assumes that the basic fingerprint pattern sequence is all ulnar loops and that a variety of genes cause deviations from this pattern sequence. Genes that have been proposed include: (1) a semidominant gene for whorls on the thumbs (one homozygote has whorls on both thumbs, the other has ulnar loops on both thumbs and the heterozygote usually has two ulnar loops or one ulnar loop and one whorl); (2) a semidominant gene for whorls on the ring fingers which acts like the gene for whorls on the thumbs; (3) a dominant gene for arches on the thumbs and often on other fingers; (4) one or more dominant genes for arches on the fingers; (5) a dominant gene for whorls on all fingers except for an ulnar loop on the middle finger; (6) a dominant gene for radial loops on the index fingers, frequently associated with an arch on the middle fingers; and (7) a recessive gene for radial loops on the ring and little fingers. These genes may act independently or may show epistasis.  相似文献   

18.
Eight hundred Nigerians (400 males and 400 females) were screened for the analysis of digital dermatoglyphic patterns. The frequency distribution of the patterns are 52.09%, 27.67%, 19.20% and 1.13% for ulnar loops, whorls, arches and radial loops respectively. Except for arches, the males have more of the patterns than females. The pattern intensity indices for males and females are 11.2 and 9.9 respectively. Bilateral symmetry is similar in both sexes and the percent distribution is as high as 81.5% and 84% on digit V in males and females respectively.  相似文献   

19.
The global pattern of variation at the homologous microsatellite loci DYS413 (Yq11) and DXS8174 and DXS8175 (Xp22) was analyzed by examination of 30 world populations from four continents, accounting for more than 1,100 chromosomes per locus. The data showed discordant patterns of among- and within-population gene diversity for the Y-linked and the X-linked microsatellites. For the Y-linked polymorphism, all groups of populations displayed high FST values (the correlation between random haplotypes within subpopulations, relative to haplotypes of the total population) and showed a general trend for the haplotypes to cluster in a population-specific way. This was especially true for sub-Saharan African populations. The data also indicated that a large fraction of the variation among populations was due to the accumulation of new variants associated with the radiation process. Europeans exhibited the highest level of within-population haplotype diversity, whereas sub-Saharan Africans showed the lowest. In contrast, data for the two X-linked polymorphisms were concordant in showing lower FST values, as compared with those for DYS413, but higher within-population variances, for African versus non-African populations. Whereas the results for the X-linked loci agreed with a model of greater antiquity for the African populations, those for DYS413 showed a confounding pattern that is apparently at odds with such a model. Possible factors involved in this differential structuring for homologous X and Y microsatellite polymorphisms are discussed.  相似文献   

20.
Flowers are determinate shoots comprised of perianth and reproductive organs displayed in a whorled phyllotactic pattern. Floral organ identity genes display region-specific expression patterns in the developing flower. In Arabidopsis, floral organ identity genes are activated by LEAFY (LFY), which functions with region-specific co-regulators, UNUSUAL FLORAL ORGANS (UFO) and WUSCHEL (WUS), to up-regulate homeotic genes in specific whorls of the flower. PENNYWISE (PNY) and POUND-FOOLISH (PNF) are redundant functioning BELL1-like homeodomain proteins that are expressed in shoot and floral meristems. During flower development, PNY functions with a co-repressor complex to down-regulate the homeotic gene, AGAMOUS (AG), in the outer whorls of the flower. However, the function of PNY as well as PNF in regulating floral organ identity in the central whorls of the flower is not known. In this report, we show that combining mutations in PNY and PNF enhance the floral patterning phenotypes of weak and strong alleles of lfy, indicating that these BELL1-like homeodomain proteins play a role in the specification of petals, stamens and carpels during flower development. Expression studies show that PNY and PNF positively regulate the homeotic genes, APETALA3 and AG, in the inner whorls of the flower. Moreover, PNY and PNF function in parallel with LFY, UFO and WUS to regulate homeotic gene expression. Since PNY and PNF interact with the KNOTTED1-like homeodomain proteins, SHOOTMERISTEMLESS (STM) and KNOTTED-LIKE from ARABIDOPSIS THALIANA2 (KNAT2) that regulate floral development, we propose that PNY/PNF-STM and PNY/PNF-KNAT2 complexes function in the inner whorls to regulate flower patterning events.  相似文献   

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