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1.
R S Balgir 《HOMO》2006,57(2):163-176
Tribal communities in India constitute the largest tribal population in the world. There are about 635 biological isolates (tribes and subtribes), which constituted 8.08% (about 84.3 million) of the total population of India as per the 2001 census. Out of 635 scheduled tribes (aborigines), 62 live in the state of Orissa alone forming about 10.8% of the tribal population of India. Orissa state occupies an important place, being the 3rd in rank for the highest concentration of tribal population in the country. In India, tribal communities are highly vulnerable to hereditary diseases and have a high degree of malnutrition, morbidity and mortality. The sickle cell haemoglobinopathy and glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency are important genetic and public health problems in Central-Eastern part of India. In order to map out these genetic disorders among the tribal people, a cross-section of 15 major tribal communities from different parts of Orissa was randomly screened for haemoglobin variants and G6PD deficiency. The high frequency of sickle cell haemoglobinopathy (0-22.4%) and G6PD deficiency (4.3-17.4%), with beta-thalassemia trait (0-8.5%) taking almost an intermediate position, was observed. For G6PD deficiency, hemizygous males as well as female heterozygotes and female homozygotes were detected. Twelve cases showed compound heterozygosity for sickle cell haemoglobinopathy and G6PD deficiency. There seems to be a trend towards an inverse relationship between the sickle cell allele and G6PD deficiency, and sickle cell and beta-thalassemia allele in a cross-section of malaria endemic (Plasmodium falciparum) tribal communities in Orissa. When the frequency of sickle cell allele decreases in a cross-section of malaria endemic tribal population, the frequency of G6PD enzyme deficiency and beta-thalassemia allele increases and vice versa. Natural selection had played a major role in favour of sickle cell, beta-thalassemia and G6PD mutation alleles so that they had probably evolved as a protective mechanism against the lethal effects of malaria in this part of the country. However, the calculated values of 0.074, 0.218 and 0.337, respectively, of Pearson's correlation co-efficient (r), showed no correlation between sickle cell disorders and G6PD deficiency, sickle cell disorders and beta-thalassemia, and G6PD deficiency and beta-thalassemia. 相似文献
2.
K D Krasnopol'skaia T L Shatskaia I K Filippov G A Annenkov T V Zakharova 《Genetika》1977,13(8):1455-1461
Examination on G6PD deficiency in 349 patients of Shekii district hospital (Azerbaijan) revealed 16 hemi-, 4 homo- and 9 heterozygotic carriers of the defect. Gd- frequency, calculated from the data obtained (7.7%), may be compared to neighbouring regions' frequencies (6-30%). Carriers of G6PD deficiency are residents of 11 villages located in Alasani-Aphtalan valley, highly endemic with malaria in the past; nearly all marriages are endogamic. Physico-chemical and kinetic study of 10 mutant forms of G6PD, according to WHO program, led to identification of 5 variants of the II class (Shekii, Bideiz, Shirin-Bulakh, Okhut I and Zakataly) and 2 variants of the III class (Okhut II and Martinique-like). Resemblance of the majority of variants in electrophoretic mobility and the level of erythrocyte enzyme activity permit to suggest the existence of a common parental mutant G6PD allele distributed in this area. 相似文献
3.
Alphaxard Manjurano Nuno Sepulveda Behzad Nadjm George Mtove Hannah Wangai Caroline Maxwell Raimos Olomi Hugh Reyburn Eleanor M. Riley Christopher J. Drakeley Taane G. Clark MalariaGEN Consortium 《PLoS genetics》2015,11(2)
X-linked Glucose-6-phosphate dehydrogenase (G6PD) A- deficiency is prevalent in sub-Saharan Africa populations, and has been associated with protection from severe malaria. Whether females and/or males are protected by G6PD deficiency is uncertain, due in part to G6PD and malaria phenotypic complexity and misclassification. Almost all large association studies have genotyped a limited number of G6PD SNPs (e.g. G6PD202 / G6PD376), and this approach has been too blunt to capture the complete epidemiological picture. Here we have identified 68 G6PD polymorphisms and analysed 29 of these (i.e. those with a minor allele frequency greater than 1%) in 983 severe malaria cases and controls in Tanzania. We establish, across a number of SNPs including G6PD376, that only female heterozygotes are protected from severe malaria. Haplotype analysis reveals the G6PD locus to be under balancing selection, suggesting a mechanism of protection relying on alleles at modest frequency and avoiding fixation, where protection provided by G6PD deficiency against severe malaria is offset by increased risk of life-threatening complications. Our study also demonstrates that the much-needed large-scale studies of severe malaria and G6PD enzymatic function across African populations require the identification and analysis of the full repertoire of G6PD genetic markers. 相似文献
4.
Bidhan Kanti Das 《International Journal of Anthropology》2006,21(2):151-163
Increased mortality and morbidity including congenital malformations among the offspring of consanguineous marriages have been widely reported in human populations from different parts of the world. However, there are few studies on the effect of the intensity of inbreeding and different degrees of inbreeding on mortality and morbidity. The present study is an attempt to examine the effects of inbreeding on mortality and morbidity including congenital disorders in different levels of inbreeding among Telugu-speaking populations of Kharagpur, West Bengal, India, based on data collected through extensive pedigrees. The study reveals that the frequency of spontaneous abortions and stillbirths is higher in the offspring of consanguineous marriages than in that of non-consanguineous marriages. A similar effect is also observed in the infant mortality rate, which is known to have a genetic component, but is not seen in the mortality rate of children and juveniles. The rate of morbidity is consistently higher in the offspring of consanguineous marriages with a sex bias in favour of inbred females. The increased morbidity rates in inbred individuals tend to be inversely correlated with the increase in average autosomal inbreeding coefficient. This appears to strengthen Sanghvi’s hypothesis of a decline in the frequency of deleterious genes with intensification of inbreeding through generations. The present study also confirms an increase in genetic disorders with an increase in inbreeding in almost all populations. 相似文献
5.
Marla K. Johnson Tamara D. Clark Denise Njama-Meya Philip J. Rosenthal Sunil Parikh 《PloS one》2009,4(9)
Background
Clinical association studies have yielded varied results regarding the impact of glucose-6-phosphate dehydrogenase (G6PD) deficiency upon susceptibility to malaria. Analyses have been complicated by varied methods used to diagnose G6PD deficiency.Methodology/Prinicipal Findings
We compared the association between uncomplicated malaria incidence and G6PD deficiency in a cohort of 601 Ugandan children using two different diagnostic methods, enzyme activity and G6PD genotype (G202A, the predominant East African allele). Although roughly the same percentage of males were identified as deficient using enzyme activity (12%) and genotype (14%), nearly 30% of males who were enzymatically deficient were wild-type at G202A. The number of deficient females was three-fold higher with assessment by genotype (21%) compared to enzyme activity (7%). Heterozygous females accounted for the majority (46/54) of children with a mutant genotype but normal enzyme activity. G6PD deficiency, as determined by G6PD enzyme activity, conferred a 52% (relative risk [RR] 0.48, 95% CI 0.31–0.75) reduced risk of uncomplicated malaria in females. In contrast, when G6PD deficiency was defined based on genotype, the protective association for females was no longer seen (RR = 0.99, 95% CI 0.70–1.39). Notably, restricting the analysis to those females who were both genotypically and enzymatically deficient, the association of deficiency and protection from uncomplicated malaria was again demonstrated in females, but not in males (RR = 0.57, 95% CI 0.37–0.88 for females).Conclusions/Significance
This study underscores the impact that the method of identifying G6PD deficient individuals has upon association studies of G6PD deficiency and uncomplicated malaria. We found that G6PD-deficient females were significantly protected against uncomplicated malaria, but this protection was only seen when G6PD deficiency is described using enzyme activity. These observations may help to explain the discrepancy in some published association studies involving G6PD deficiency and uncomplicated malaria. 相似文献6.
This paper reports the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the male and female population of A1-Ula in the northwestern province of Saudi Arabia. The frequency of G6PD deficiency in the male population was 0.098 and in the females it was 0.028. This frequency is significantly lower than those reported for other malaria endemic regions in Arabia. The population was further subgrouped on the basis of their haemoglobin phenotypes and the highest frequency of G6PD deficiency was obtained in male Hb S heterozygotes followed by the male Hb S homozygotes. Phenotyping of G6PD revealed the presence of G6PD-Mediterranean, G6PDA+, G6PDA- and G6PD Mediterranean-like, and the frequency of these variants in Al-Ula was different from those reported in other regions of Saudi Arabia. 相似文献
7.
The average inbreeding coefficients of the highly consanguineous Fur and Baggara tribes of Western Sudan were 0.04167 and 0.04450, respectively. Two hundred ninety-eight subjects from the two tribes were tested for polymorphism of hemoglobins, seven red cell enzymes, and four serum proteins. The Baggara showed a higher gene frequency of HbS and TfD and lower gene frequency of GdA and PC compared to the Fur. Both tribes showed a low gene frequency of PGM1 and high frequency of G6PD deficiency when compared to other Sudanese tribes. In spite of the high degree of inbreeding, no significant deviation from the Hardy-Weinburg equilibrium was observed in either tribe. The effects of inbreeding seem to be offset by mixing between the two tribes on Gabal Marra Plateau. The flow of the sickle gene from the Baggara into the Fur and other Sudanese tribes is discussed. 相似文献
8.
R Palmarino R Agostino F Gloria P Lucarelli L Businco G Antognoni G Maggioni P L Workman E Bottini 《American journal of physical anthropology》1975,43(2):177-186
The frequency of PC allele for acid phosphatase in fourteen Sardinian villages correlates positively with the altitude and negatively with past malarial morbidity and GdMed prevalence. The susceptibility towards hemolytic favism in Sardinian males with G6PD deficiency is dependent on the erythrocyte acid phosphatase and thalassemia phenotypes. Thalassemia trait exerts a protective action only in subjects carrying PA allele for acid phosphatase. The data suggest that the gradient for malaria morbidity directly or indirectly, through interactions with thalassemia and G6PD polymorphisms, mediated by the habit of eating Vecia faba, may have had a significant role in determining the heterogeneous distribution of acid phosphatase polymorphism in Sardinia. Besides malaria, other environmental factors related with altitude seem to have been very important in shaping the present pattern of distribution of both acid phosphatase and G6PD polymorphisms in Sardinia. 相似文献
9.
The harmful effects of inbreeding can be reduced if deleterious recessive alleles were removed (purged) by selection against homozygotes in earlier generations. If only a few generations are involved, purging is due almost entirely to recessive alleles that reduce fitness to near zero. In this case the amount of purging and allele frequency change can be inferred approximately from pedigree data alone and are independent of the allele frequency. We examined pedigrees of 59,778 U.S. Jersey cows. Most of the pedigrees were for six generations, but a few went back slightly farther. Assuming recessive homozygotes have fitness 0, the reduction of total genetic load due to purging is estimated at 17%, but most of this is not expressed, being concealed by dominant alleles. Considering those alleles that are currently expressed due to inbreeding, the estimated amount of purging is such as to reduce the expressed load (inbreeding depression) in the current generation by 12.6%. That the reduction is not greater is due mainly to (1) generally low inbreeding levels because breeders in the past have tended to avoid consanguineous matings, and (2) there is essentially no information more than six generations back. The methods used here should be applicable to other populations for which there is pedigree information. 相似文献
10.
Ebrahim Miri-Moghaddam Yousef Mortazavi Alireza Nakhaee Abdurrashid Khazaei Feizabad 《Biochemical genetics》2013,51(1-2):131-138
To determine the prevalence of G6PD deficiency and a Mediterranean mutation among males in southeastern Iran, we studied 1,097 Sistani and Balouch schoolboys. A questionnaire was used to collect demographic data and a history of malaria infection; blood samples were evaluated for G6PD deficiency and the G6PD Mediterranean mutation. Of the 1,097 boys screened, 175 were G6PD deficient (5.8 % of the Sistani boys and 19.3 % of the Balouch boys). The malaria survey indicated that among Balouch subjects, malaria infection was about 14 times that of Sistani subjects. Molecular characterization of G6PD-deficient samples revealed a general frequency of 85.1 % for the Mediterranean variant among all subjects (75 % among Sistani and 86.2 % among Balouch cases). The high prevalence of G6PD deficiency among Balouch populations confirms the hypothesis that the distribution of G6PD deficiency is concordant with the geographic distribution of malaria. 相似文献
11.
Glucose 6-phosphate dehydrogenase deficiency and incidence of hematologic malignancy. 总被引:1,自引:0,他引:1
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A M Ferraris G Broccia T Meloni G Forteleoni G F Gaetani 《American journal of human genetics》1988,42(3):516-520
We have evaluated the hypothesis of a negative association between glucose 6-phosphate dehydrogenase (G6PD) deficiency and cancer in a cohort of 481 Sardinian males with hematological malignancies. The frequency of G6PD deficiency in the patients was not different from the incidence in a group of 16,219 controls. The same conclusion resulted from the comparison of the frequency of expression of the GdB gene in 23 heterozygous women having a clonal hematologic disease and a control group of 37 healthy heterozygotes. Therefore at present there is no evidence that G6PD deficiency has a protective effect against development of hematologic neoplasms. 相似文献
12.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in humans. Deficiency alleles for this X-linked disorder are geographically correlated with historical patterns of malaria, and the most common deficiency allele in Africa (G6PD A-) has been shown to confer some resistance to malaria in both hemizygous males and heterozygous females. We studied DNA sequence variation in 5.1 kb of G6pd from 47 individuals representing a worldwide sample to examine the impact of selection on patterns of human nucleotide diversity and to infer the evolutionary history of the G6PD A- allele. We also sequenced 3.7 kb of a neighboring locus, L1cam, from the same set of individuals to study the effect of selection on patterns of linkage disequilibrium. Despite strong clinical evidence for malarial selection maintaining G6PD deficiency alleles in human populations, the overall level of nucleotide heterozygosity at G6pd is typical of other genes on the X chromosome. However, the signature of selection is evident in the absence of genetic variation among A- alleles from different parts of Africa and in the unusually high levels of linkage disequilibrium over a considerable distance of the X chromosome. In spite of a long-term association between Plasmodium falciparum and the ancestors of modern humans, patterns of nucleotide variability and linkage disequilibrium suggest that the A- allele arose in Africa only within the last 10,000 years and spread due to selection. 相似文献
13.
Méndez D Linares M Diez A Puyet A Bautista JM 《Free radical biology & medicine》2011,50(10):1305-1313
Multiple glucose-6-phosphate dehydrogenase (G6PD)-deficient alleles have reached polymorphic frequencies because of the protection they confer against malaria infection. A protection mechanism based on enhanced phagocytosis of parasitized G6PD-deficient erythrocytes that are oxidatively damaged is well accepted. Although an association of this phenotype with the impairment of the antioxidant defense in G6PD deficiency has been demonstrated, the dysfunctional pathway leading to membrane damage and modified exposure of the malaria-infected red cell to the host is not known. Thus, in this study, erythrocytes from the common African variant G6PD A- were used to analyze by redox proteomics the major oxidative changes occurring in the host membrane proteins during the intraerythrocytic development of Plasmodium falciparum, the most lethal malaria parasite. Fifteen carbonylated membrane proteins exclusively identified in infected G6PD A- red blood cells revealed selective oxidation of host proteins upon malarial infection. As a result, three pathways in the host erythrocyte were oxidatively damaged in G6PD A-: (1) traffic/assembly of exported parasite proteins in red cell cytoskeleton and surface, (2) oxidative stress defense proteins, and (3) stress response proteins. Additional identification of hemichromes associated with membrane proteins also supports a role for specific oxidative modifications in protection against malaria by G6PD polymorphisms. 相似文献
14.
Knowledge of the G6PD genotype and its associated enzyme activity is significant for population genetics, diagnosis of disease, and management of patients. We tested 2,872 unrelated subjects from a Hakka population in China for G6PD activity by the WHO standard method and for genotype by DHPLC and DNA sequencing. Among female heterozygotes, 78.5% had relatively normal enzyme activity. The phenotype frequency of G6PD deficiency is 0.028, and the causal allele frequency is 0.060 in females. The accuracy, sensitivity, and specificity of DHPLC are more than 98% for detecting G6PD-deficient hemizygotes, heterozygotes, and homozygotes. Measuring enzyme activity alone is not sufficient for the diagnosis of heterozygotes. A combination of enzyme activity and DNA analysis should be used. 相似文献
15.
Glucose-6-phosphate dehydrogenase (G6PD) and hemoglobin E (HbE) were studied among 708 malarial patients and control groups of Ao Nagas from the Mokokchung District of Nagaland in the extreme northeast of India. The data suggest that malaria is an important ecologic factor in maintaining the high frequency of G6PD deficiency and HbE among the Ao Nagas. Although migrations from adjoining populations that have a high frequency of both these traits could have contributed to the presence of these genes in the Ao Nagas, malaria also could be an essential determinant in maintaining the current high frequency in present-day Ao Nagas. 相似文献
16.
A total of 1,112 randomly selected Saudi Arabs, of both sexes, living in Jeddah and the surrounding areas were screened for the phenotypic distribution of red cell glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD). They were also investigated for haemoglobin and for thalassaemia. Phenotyping of the haemoglobins and the red cell enzymes was carried out by starch gel electrophoresis and the dye-decolouration screening test, while the investigation for thalassaemia was carried out by globin-chain biosynthesis, followed by column chromatography. The red cell Gd- alleles were significantly associated with the sickle-cell gene in both the males (chi 2(1): AS-28.80; SS-4.89) and females (chi 2(1): AS-10.99; SS-13.16). A similar association was also observed between G6PD deficiency and thalassaemias in males (chi 2(1): alpha-thalassaemia - 3.13; beta-thalassaemia - 11.06) and females (chi 2(1): alpha-thalassaemia - 6.63). However, no such association was detected between red cell 6PGD types and haemoglobin genes. The results suggest that the red cell G6PD deficiency, sickle-cell and thalassaemia genes might have evolved as a result of the same ecological factor, probably malaria. 相似文献
17.
Giuseppe Martini Matilde Valeria Ursini 《BioEssays : news and reviews in molecular, cellular and developmental biology》1996,18(8):631-637
We review here some recent data about glucose-6-phosphate dehydrogenase (G6PD), the first and key regulatory enzyme of the pentose phosphate pathway. New evidence has been presented to suggest that malaria is a selective agent for G6PD deficiency, which is the most common enzymopathy in man, and that G6PD deficiency, generally considered to be a mild and benign condition, is significantly disadvantageous in certain environmental conditions. At the molecular level, the enzyme structure has recently been elucidated and mechanisms regulating G6PD gene expression have been determined. A G6PD knock-out mutation introduced in mouse cells makes them exquisitely sensitive to oxidative stress, indicating that this ubiquitous metabolic enzyme has a major role in the defence against oxidative stress, even in eukaryotic nucleated cells, which have several alternative routes for providing the same protection. Because of the high prevalence of G6PD deficiency in many populations, it is expected that these findings will prompt further studies to ascertain the putative role of G6PD deficiency in conditions such as carcinogenesis and ageing. 相似文献
18.
A Valls 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》1985,43(1):59-68
Using data from parish records from 1712 to 1982 in a Spanish Pyrenean village, Ansó, the effects of the raw nuptiality, the types of consanguineous marriages and the rate and evolution of inbreeding on the mating structure have been studied. This structure has been modified in the course of time mostly through the secular variations in the frequency of consanguineous marriages. Recent inbreeding decrease in Ansó is related to the population diminution and cultural changes associated with isolate breakdown. 相似文献
19.
Nicholas Amoako Kwaku Poku Asante George Adjei Gordon A. Awandare Langbong Bimi Seth Owusu-Agyei 《PloS one》2014,9(12)
Background
Red blood cell (RBC) polymorphisms are common in malaria endemic regions and are known to protect against severe forms of the disease. Therefore, it is important to screen for these polymorphisms in drugs or vaccines efficacy trials. This study was undertaken to evaluate associations between clinical malaria and RBC polymorphisms to assess biological interactions that may be necessary for consideration when designing clinical trials.Method
In a cross-sectional study of 341 febrile children less than five years of age, associations between clinical malaria and common RBC polymorphisms including the sickle cell gene and G6PD deficiency was evaluated between November 2008 and June 2009 in the middle belt of Ghana, Kintampo. G6PD deficiency was determined by quantitative methods whiles haemoglobin variants were determined by haemoglobin titan gel electrophoresis. Blood smears were stained with Giemsa and parasite densities were determined microscopically.Results
The prevalence of clinical malarial among the enrolled children was 31.9%. The frequency of G6PD deficiency was 19.0% and that for the haemoglobin variants were 74.7%, 14.7%, 9.1%, 0.9% respectively for HbAA, HbAC, HbAS and HbSS. In Multivariate regression analysis, children with the HbAS genotype had 79% lower risk of malaria infection compared to those with the HbAA genotypes (OR = 0.21, 95% CI: 0.06–0.73, p = 0.01). HbAC genotype was not significantly associated with malaria infection relative to the HbAA genotype (OR = 0.70, 95% CI: 0.35–1.42, p = 0.33). G6PD deficient subgroup had a marginally increased risk of malaria infection compared to the G6PD normal subgroup (OR = 1.76, 95% CI: 0.98–3.16, p = 0.06).Conclusion
These results confirm previous findings showing a protective effect of sickle cell trait on clinical malaria infection. However, G6PD deficiency was associated with a marginal increase in susceptibility to clinical malaria compared to children without G6PD deficiency. 相似文献20.
Blanco Villegas MJ Boattini A Otero HR Pettener D 《Human biology; an international record of research》2004,76(2):191-210
Marital structure and inbreeding coefficients were analyzed in La Cabrera, an isolated mountain region in northwestern Spain. A total of 5,714 marriages were celebrated from 1880 to 1989 in the 37 parishes of the area. The total frequency of consanguineous marriages (up to the fourth degree) is 23.05%; multiple consanguineous marriages are remarkably common, reaching 5.43% of the total. The first cousin/second cousin ratio (referred to as kinship-type frequencies) is 0.43. The inbreeding values are the highest recorded in Spain and in Europe: alpha3 is 4.82 x 10(-3) for the whole period and alpha4 is 6.78 x 10(-3) for 1880--1919. The temporal trend of inbreeding shows high values (alpha3 > 4.5 x 10(-3)) for a particularly long period (1900--1959) and a rapid decline from 1960 onward. This historical inbreeding trend is clearly related to changes in population size. The frequencies of multiple consanguineous marriages and the analysis of isonymy show that the inbreeding structure is related to geographic and demographic factors. Comparing the results at two hierarchical levels (La Cabrera as a whole and the 37 parishes individually), we conclude that the inbreeding values are affected by internal geographic subdivision of the population (Wahlund effect). Social and cultural factors, such as avoidance of or preference for consanguineous marriages, are less important but depend on the kinship type involved. 相似文献