The PowerPlex Ò 16 System from Promega Corporation allows single tube multiplex amplification of ... more The PowerPlex Ò 16 System from Promega Corporation allows single tube multiplex amplification of sixteen short tandem repeat (STR) loci including all 13 core combined DNA index system STRs. This report presents an updated validation of the PowerPlex Ò 16 System on Applied Biosystem's 96 capillary 3730xl DNA Analyzer. The validation protocol developed in our laboratory allows for the analysis of 1536 loci (96 • 16) in c. 50 min. We have further optimized the assay by decreasing the reaction volume to one-quarter that recommended by the manufacturer thereby substantially reducing the total cost per sample without compromising reproducibility or specificity. This reduction in reaction volume has the ancillary benefit of dramatically increasing the sensitivity of the assay allowing for accurate analysis of lower quantities of DNA. Due to its substantially increased throughput capability, this extended validation of the PowerPlex Ò 16 System should be useful in reducing the backlog of unanalyzed DNA samples currently facing public DNA forensic laboratories.
The Anopheles punctulatus (Diptera: Culicidae) group is the main vector for malaria and Bancrofti... more The Anopheles punctulatus (Diptera: Culicidae) group is the main vector for malaria and Bancroftian Þlariasis in Vanuatu. Anopheles larvae were collected from 10 localities on Þve islands of Vanuatu during the 2004 dry season for species identiÞcation as well as for estimating population structure and gene ßow within and among islands. Species identiÞcation was determined using polymerase chain reaction-restriction fragment length polymorphism analysis of the internal transcribed spacer 2 region. Population structure and gene ßow were examined by sequencing a portion of the ND4/ND5 region of the mitochondrial genome. Only one species of the An. punctulatus group, An. farauti s.s., was identiÞed, consistent with previous studies in Vanuatu. A nonrandom distribution of An. farauti s.s. lineages was observed with one cosmopolitan lineage shared by eight sites on all Þve islands and a preponderance of island-speciÞc lineages (36/40), indicating the introduction of a single main lineage into Vanuatu followed by dispersal, diversiÞcation, and limited lineage exchange between islands. Network analysis suggests a possible second introduction of An. farauti s.s. into the northern islands of Gaua and Malekula. Gene ßow was high on three of the Þve islands, whereas Tanna and Santo have signiÞcant population structure. Among islands, gene ßow was limited, indicating active mosquito dispersal only over short distances and a paucity of passive human-mediated dispersal over long distances. Minimal risk of active dispersal among these islands indicates that vector control can be effectively initiated at the island level within the archipelago of Vanuatu.
15 Contributions of Population Origins and Gene Flow to the Diversity of Neutral and Malaria Sele... more 15 Contributions of Population Origins and Gene Flow to the Diversity of Neutral and Malaria Selected Autosomal Genetic Loci of Pacific Island Populations J. Koji Lum Introduction The ability of a population to adapt to its environment and respond effectively to its pathogens ...
Two polymorphic sites,-107 and-100 with respect to the "cap" site of the human beta globin pseudo... more Two polymorphic sites,-107 and-100 with respect to the "cap" site of the human beta globin pseudogene, recently discovered in our laboratory, turned out to have an ethnically complementary distribution. The first site is polymorphic in Europeans, North Africans, Indians (Hindu), and Oriental Asians, and monomorphic in sub-Saharan Africans. Conversely, the second site is polymorphic in sub-Saharan African populations and monomorphic in the aforementioned populations. Here we report the gene frequencies of these two polymorphic sites in nine additional populations (Egyptians, Spaniards, Japanese, Chinese, Filipinos, Vietnamese, Africans from Togo and from Benin, and Pygmies), confirming their ethnospecificity and, through the analysis of these two markers in Oromo and Amhara of Ethiopia (two mixed populations), their usefulness in genetic admixture studies. Moreover, we studied another marker polymorphic in sub-Saharan African populations only, a TaqI restriction fragment length polymorphism located in the same region as the present markers, demonstrating the absence of linkage disequilibrium between it and the-100 site, so that we can exclude that the information they provide is redundant.
The prevalence of a 9-base-pair (bp) deletion between the mitochondrial cytochrome oxidase II (MT... more The prevalence of a 9-base-pair (bp) deletion between the mitochondrial cytochrome oxidase II (MTCOX*2) and lysine tRNA (MTTK) genes (region V) has been used to estimate the genetic relationships among Asian and Pacific populations. Many East Asian and Pacific Island populations have been examined previously, but the mitochondrial DNA (mtDNA) diversity of the intervening Indonesian archipelago has not previously been systematically examined. The 17,500 islands of Indonesia currently contain nearly 213 million people and extensive cultural, linguistic, and, presumably, genetic diversity. This study of 1091 individuals representing 15 ethnic groups is the most extensive mtDNA survey to date of the Indonesian archipelago. Six distinct length polymorphisms in region V were observed within these 15 populations. The 9-bp deletion was found in every population examined at frequencies comparable to those of previously examined East Asian populations and substantially lower than those in most Pacific Island populations. Despite the inclusion of Austronesian-speaking populations and a Papuan-speaking population, there was no statistically significant heterogeneity in the frequency of the 9-bp deletion among the 15 populations (p = 0.09). These data indicate that substantial gene flow occurred among the populations at some time in the past. Our observations of no significant correlations between genetic and geographic distances (r =-0.04, p = 0.53) coupled with the extensive cultural and linguistic differences currently within the archipelago suggest that little gene flow among neighboring populations has occurred recently. The Indonesian archipelago consists of more than 17,500 islands (Rais 1997) dispersed across an area as vast as the continental United States of America, with a total area of 1,919,440 square kilometers (Figure 1). The inhabitants of this archi
Interdisciplinary contributions to archaeology, 1994
Anthropologists who study human evolution today, especially the later stages, have many advantage... more Anthropologists who study human evolution today, especially the later stages, have many advantages over scientists working on human origins 50 years ago. Biotechnology and the discovery of new fossils in situ help us deduce that some lineages of humans survived and some perished without leaving modern descendants. This information is crucial for understanding the major transitions in human evolution, whether the problem at hand is the origin of bipedalism, or in our case in this volume, the origin of anatomically modern people. This chapter will discuss the contribution that genetics and specifically, studies of maternally inherited genes, have made to furthering our understanding of where and when modern humans arose. It will summarize the insights of many scientists. In the end, we will make a plea for better experimental models which allow us to get at the actual numbers, e.g., how many generations does a morphological transition take, how many ancestors (original founders) were involved, how much genetic isolation was needed, how many survivors were there, and what were the rates of subdivision, rates of extinction, and rates of at which populations expanded? This focus derives from our work on Polynesian migration to Hawaii, lineage extinction and stability, and demographic change due to the introduction of infectious diseases by colonizers to aboriginal peoples.
Advancements in Artificial Intelligence (AI) and Big Data technologies are reshaping the global e... more Advancements in Artificial Intelligence (AI) and Big Data technologies are reshaping the global economy. The community currency network is receiving more attention through enhancing social ties within a community. As the most popular type of community currency, Time Banking (TB) is a generalized community exchange economy, which uses the time to evaluate each participant’s contributions on the same scale rather than any equivalence with the official national currency. TB is a noble idea with the potential to improve the quality of life through prosocial, reciprocally beneficial activities among community members. However, it also brings new concerns about security and trust issues. Inspired by blockchain and smart contract, this paper introduces a Blockchain Integrated Timebanking (BIT) system to secure a decentralized community exchange economy. In BIT system, service providers and recipients can securely exchange effort through a self-executing smart contract without relying on a third-party trust authority. The blockchain network ensures immutability, auditability, and traceability of all data and service transactions recorded on the distributed ledger. A proof-of-concept prototype was implemented and tested on a private Ethereum network. The experimental results verify the feasibility of the proposed BIT to provide decentralized community service exchanges with limited computation overhead and network latency.
Blockchain technology is reshaping the the traditional economies. People may have more trust than... more Blockchain technology is reshaping the the traditional economies. People may have more trust than ever before as the transaction is immutable and transparent. Success in crypto-currency and other technical areas highlights many attractive features of the blockchain technology that can benefit more aspects of modern society. Time Banking is a generalized exchange economy not based on money, but values everyone's contribution on the same scale, the time expended. Time banking is a noble idea with great potential, but the security and trust issues are not well addressed. In this paper a BLockchain-ENabled Decentralized Time Banking System (BlendTBS)is proposed to build a trustful, dynamic and respectful community. People in this community are encouraged to be engaged in mutual serving relationships. For this purpose, the BlendTBS is designed to reward the residents who commit in socially beneficial activities. An initial prototype is implemented on a permissioned blockchain network and a small scale study is planned to examine the utility of BlendTBS to a traditional community on the island of Aneityum, Republic of Vanuatu. Within a selected community in the village of Analgahuat, deeper insights will be explored by observing the trust enabled by Blockchain technology that allows peer to peer service exchanges between any two individuals. Authors hope this position paper may inspire more interests in the roles that blockchain technology can play in modern society.
Tropical Medicine & International Health, Jun 1, 2005
SummaryTumour necrosis factor‐alpha (TNF‐α) is one of the key cytokines that influence the pathol... more SummaryTumour necrosis factor‐alpha (TNF‐α) is one of the key cytokines that influence the pathology of microbial infections. The genetic susceptibility to severe forms of falciparum malaria is differentially associated with TNF‐α promoter gene polymorphisms (TNFP alleles). In a previous study, we identified a TNFP‐allele characterized by a C to T transition at position −857 (TNFP‐D allele) as a marker for susceptibility to cerebral malaria in Myanmar. The frequencies of TNFP alleles on six islands of Vanuatu, Melanesia (South‐west Pacific) were estimated to investigate whether malaria selection pressure on this susceptibility marker has influenced its prevalence. Within the archipelago of Vanuatu there is a decreasing cline of parasite incidence from North to South. Of the four alleles of the TNFP gene detected in Vanuatu, the TNFP‐D allele frequencies were inversely correlated with the parasite incidence of islands; TNFP‐D varied from 0.55 on the island with the lowest parasite incidence to 0.26 on the island with the highest parasite incidence (r = −0.855, P = 0.03). We also observed a significant correlation between the frequencies of α‐thalassaemia alleles, thought to protect against malaria and parasite incidence in the same populations. These data are consistent with a previously reported correspondence between the frequencies of glucose 6‐phosphate dehydrogenase (G6PD) deficiency and parasite incidences on the islands of Vanuatu (Kaneko et al. 1998) and indicate that the degree of malaria endemicity has influenced the allele frequencies of at least three loci that confer both susceptibility (TNFP‐D) and protection (α‐thalassaemias and G6PD deficiency).
A comparison of the patterns of gene flow within and between islands and the genetic diversities ... more A comparison of the patterns of gene flow within and between islands and the genetic diversities of the three species required for malaria transmission (humans, Plasmodium falciparum, and Anopheles farauti s.s.) within the model island system of Vanuatu, shows that the active dispersal of An. farauti s.s. is responsible for within island movement of parasites. In contrast, since both P. falciparum and An. farauti s.s. populations are largely restricted to islands, movement of parasites between islands is likely due to human transport. Thus, control of vectors is crucial for controlling malaria within islands, while control of human movement is essential to control malaria transmission across the archipelago.
The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has... more The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has been determined. Several polymorphisms in the hOGG1 gene were detected in the Japanese populations, and among them, the Ser-Cys polymorphism at codon 326 has been shown to have a functional difference in complementation of mutant Escherichia coli that is defective in the repair of 8-hydroxyguanine. Activity in the repair of 8-hydroxyguanine is greater in hOGG1-Ser326 protein than in hOGG1(326) protein. Because many environmental carcinogens produce 8-hydroxyguanine residue and mismatching to this modified base potentially causes oncogenic mutations, the capacity to repair these lesions can be involved in cancer susceptibility in human beings. We, therefore, examined allele distributions of the Ser326Cys polymorphism in a case-control study of male lung cancer in Okinawa. The analyses based on 241 cases and 197 hospital controls disclosed the following findings. (a) Those with the Cys/Cys genotype were at an increased risk of squamous cell carcinoma and nonadenocarcinoma compared to those with the Ser/Cys and those with the Ser/Ser genotypes combined. The odds ratios adjusted for age and smoking history were 3.01 (95% confidence interval, 1.33-6.83) and 2.18 (95% confidence interval, 1.05-4.54), respectively. (b) The odds ratios for other histological subtypes of lung cancer or those in total were not significant. Those for Cys/Cys or Ser/Cys genotype against Ser/Ser did not reach statistical significance in any cell type. (c) The distributions of this polymorphism varied for different populations (Chinese, Japanese, Micronesians, Melanesians, Hungarians, and Australian Caucasians), with much less prevalence of Cys allele in the latter three populations. Although our sample size was limited, these results indicate that the Ser326Cys variant may be related to squamous cell lung cancer susceptibility. The Cys/Cys genotype appears to be more susceptible to squamous cell carcinoma, although the risk is less than that previously reported to be associated with the CYP1A1 gene. Further studies are needed to assess the importance of the interpopulation variation to cancer susceptibility.
Determinants of the use of insecticide-treated bed nets on islands of pre- and post-malaria n of ... more Determinants of the use of insecticide-treated bed nets on islands of pre- and post-malaria n of the health belief efforts when transmission continues to occur, while the results from Aneityum suggest the possibility of continued Watanabe et al. Malaria Journal 2014, 13:441
Understanding the transmission and movement of Plasmodium parasites is crucial for ma-laria elimi... more Understanding the transmission and movement of Plasmodium parasites is crucial for ma-laria elimination and prevention of resurgence. Located at the limit of malaria transmission in the Pacific, Vanuatu is an ideal candidate for elimination programs due to low endemicity and the isolated nature of its island setting. We analyzed the variation in the merozoite sur-face protein 1 (msp1) and the circumsporozoite protein (csp) of P. falciparum and P. vivax populations to examine the patterns of gene flow and population structures among seven sites on five islands in Vanuatu. Genetic diversity was in general higher in P. vivax than P. falciparum from the same site. In P. vivax, high genetic diversity was likely maintained by greater extent of gene flow among sites and among islands. Consistent with the different patterns of gene flow, the proportion of genetic variance found among islands was substan-tially higher in P. falciparum (28.81–31.23%) than in P. vivax (-0.53–3.99%). Our data s...
<p>a) Evaluation of different surface sterilization protocols. Lane 1: DNA ladder, 2: Ac, 3... more <p>a) Evaluation of different surface sterilization protocols. Lane 1: DNA ladder, 2: Ac, 3:Al, 4:Bl, 5:AlBl, 6:AlAc, 7:AcBl, 8:AlAcBl, 9,12:Extract control, 10:Alcohol, 11:Spike, 13: PCR -ve. b) Effectiveness of surface sterilization. Halite crystals (modern Saline Valley) spiked with different amounts of human DNA. Lane 1: DNA ladder, Lanes 2,3,10,11: 1.5 ng spike, Lanes 4,5,12,13: 3.0 ng spike, Lanes 6,7,14,15: 4.5 ng spike, Lanes 8,9,16,17: no spike. Lanes 2–9: no surface sterilization. Lanes 10–17 surface sterilized.</p
The PowerPlex Ò 16 System from Promega Corporation allows single tube multiplex amplification of ... more The PowerPlex Ò 16 System from Promega Corporation allows single tube multiplex amplification of sixteen short tandem repeat (STR) loci including all 13 core combined DNA index system STRs. This report presents an updated validation of the PowerPlex Ò 16 System on Applied Biosystem's 96 capillary 3730xl DNA Analyzer. The validation protocol developed in our laboratory allows for the analysis of 1536 loci (96 • 16) in c. 50 min. We have further optimized the assay by decreasing the reaction volume to one-quarter that recommended by the manufacturer thereby substantially reducing the total cost per sample without compromising reproducibility or specificity. This reduction in reaction volume has the ancillary benefit of dramatically increasing the sensitivity of the assay allowing for accurate analysis of lower quantities of DNA. Due to its substantially increased throughput capability, this extended validation of the PowerPlex Ò 16 System should be useful in reducing the backlog of unanalyzed DNA samples currently facing public DNA forensic laboratories.
The Anopheles punctulatus (Diptera: Culicidae) group is the main vector for malaria and Bancrofti... more The Anopheles punctulatus (Diptera: Culicidae) group is the main vector for malaria and Bancroftian Þlariasis in Vanuatu. Anopheles larvae were collected from 10 localities on Þve islands of Vanuatu during the 2004 dry season for species identiÞcation as well as for estimating population structure and gene ßow within and among islands. Species identiÞcation was determined using polymerase chain reaction-restriction fragment length polymorphism analysis of the internal transcribed spacer 2 region. Population structure and gene ßow were examined by sequencing a portion of the ND4/ND5 region of the mitochondrial genome. Only one species of the An. punctulatus group, An. farauti s.s., was identiÞed, consistent with previous studies in Vanuatu. A nonrandom distribution of An. farauti s.s. lineages was observed with one cosmopolitan lineage shared by eight sites on all Þve islands and a preponderance of island-speciÞc lineages (36/40), indicating the introduction of a single main lineage into Vanuatu followed by dispersal, diversiÞcation, and limited lineage exchange between islands. Network analysis suggests a possible second introduction of An. farauti s.s. into the northern islands of Gaua and Malekula. Gene ßow was high on three of the Þve islands, whereas Tanna and Santo have signiÞcant population structure. Among islands, gene ßow was limited, indicating active mosquito dispersal only over short distances and a paucity of passive human-mediated dispersal over long distances. Minimal risk of active dispersal among these islands indicates that vector control can be effectively initiated at the island level within the archipelago of Vanuatu.
15 Contributions of Population Origins and Gene Flow to the Diversity of Neutral and Malaria Sele... more 15 Contributions of Population Origins and Gene Flow to the Diversity of Neutral and Malaria Selected Autosomal Genetic Loci of Pacific Island Populations J. Koji Lum Introduction The ability of a population to adapt to its environment and respond effectively to its pathogens ...
Two polymorphic sites,-107 and-100 with respect to the "cap" site of the human beta globin pseudo... more Two polymorphic sites,-107 and-100 with respect to the "cap" site of the human beta globin pseudogene, recently discovered in our laboratory, turned out to have an ethnically complementary distribution. The first site is polymorphic in Europeans, North Africans, Indians (Hindu), and Oriental Asians, and monomorphic in sub-Saharan Africans. Conversely, the second site is polymorphic in sub-Saharan African populations and monomorphic in the aforementioned populations. Here we report the gene frequencies of these two polymorphic sites in nine additional populations (Egyptians, Spaniards, Japanese, Chinese, Filipinos, Vietnamese, Africans from Togo and from Benin, and Pygmies), confirming their ethnospecificity and, through the analysis of these two markers in Oromo and Amhara of Ethiopia (two mixed populations), their usefulness in genetic admixture studies. Moreover, we studied another marker polymorphic in sub-Saharan African populations only, a TaqI restriction fragment length polymorphism located in the same region as the present markers, demonstrating the absence of linkage disequilibrium between it and the-100 site, so that we can exclude that the information they provide is redundant.
The prevalence of a 9-base-pair (bp) deletion between the mitochondrial cytochrome oxidase II (MT... more The prevalence of a 9-base-pair (bp) deletion between the mitochondrial cytochrome oxidase II (MTCOX*2) and lysine tRNA (MTTK) genes (region V) has been used to estimate the genetic relationships among Asian and Pacific populations. Many East Asian and Pacific Island populations have been examined previously, but the mitochondrial DNA (mtDNA) diversity of the intervening Indonesian archipelago has not previously been systematically examined. The 17,500 islands of Indonesia currently contain nearly 213 million people and extensive cultural, linguistic, and, presumably, genetic diversity. This study of 1091 individuals representing 15 ethnic groups is the most extensive mtDNA survey to date of the Indonesian archipelago. Six distinct length polymorphisms in region V were observed within these 15 populations. The 9-bp deletion was found in every population examined at frequencies comparable to those of previously examined East Asian populations and substantially lower than those in most Pacific Island populations. Despite the inclusion of Austronesian-speaking populations and a Papuan-speaking population, there was no statistically significant heterogeneity in the frequency of the 9-bp deletion among the 15 populations (p = 0.09). These data indicate that substantial gene flow occurred among the populations at some time in the past. Our observations of no significant correlations between genetic and geographic distances (r =-0.04, p = 0.53) coupled with the extensive cultural and linguistic differences currently within the archipelago suggest that little gene flow among neighboring populations has occurred recently. The Indonesian archipelago consists of more than 17,500 islands (Rais 1997) dispersed across an area as vast as the continental United States of America, with a total area of 1,919,440 square kilometers (Figure 1). The inhabitants of this archi
Interdisciplinary contributions to archaeology, 1994
Anthropologists who study human evolution today, especially the later stages, have many advantage... more Anthropologists who study human evolution today, especially the later stages, have many advantages over scientists working on human origins 50 years ago. Biotechnology and the discovery of new fossils in situ help us deduce that some lineages of humans survived and some perished without leaving modern descendants. This information is crucial for understanding the major transitions in human evolution, whether the problem at hand is the origin of bipedalism, or in our case in this volume, the origin of anatomically modern people. This chapter will discuss the contribution that genetics and specifically, studies of maternally inherited genes, have made to furthering our understanding of where and when modern humans arose. It will summarize the insights of many scientists. In the end, we will make a plea for better experimental models which allow us to get at the actual numbers, e.g., how many generations does a morphological transition take, how many ancestors (original founders) were involved, how much genetic isolation was needed, how many survivors were there, and what were the rates of subdivision, rates of extinction, and rates of at which populations expanded? This focus derives from our work on Polynesian migration to Hawaii, lineage extinction and stability, and demographic change due to the introduction of infectious diseases by colonizers to aboriginal peoples.
Advancements in Artificial Intelligence (AI) and Big Data technologies are reshaping the global e... more Advancements in Artificial Intelligence (AI) and Big Data technologies are reshaping the global economy. The community currency network is receiving more attention through enhancing social ties within a community. As the most popular type of community currency, Time Banking (TB) is a generalized community exchange economy, which uses the time to evaluate each participant’s contributions on the same scale rather than any equivalence with the official national currency. TB is a noble idea with the potential to improve the quality of life through prosocial, reciprocally beneficial activities among community members. However, it also brings new concerns about security and trust issues. Inspired by blockchain and smart contract, this paper introduces a Blockchain Integrated Timebanking (BIT) system to secure a decentralized community exchange economy. In BIT system, service providers and recipients can securely exchange effort through a self-executing smart contract without relying on a third-party trust authority. The blockchain network ensures immutability, auditability, and traceability of all data and service transactions recorded on the distributed ledger. A proof-of-concept prototype was implemented and tested on a private Ethereum network. The experimental results verify the feasibility of the proposed BIT to provide decentralized community service exchanges with limited computation overhead and network latency.
Blockchain technology is reshaping the the traditional economies. People may have more trust than... more Blockchain technology is reshaping the the traditional economies. People may have more trust than ever before as the transaction is immutable and transparent. Success in crypto-currency and other technical areas highlights many attractive features of the blockchain technology that can benefit more aspects of modern society. Time Banking is a generalized exchange economy not based on money, but values everyone's contribution on the same scale, the time expended. Time banking is a noble idea with great potential, but the security and trust issues are not well addressed. In this paper a BLockchain-ENabled Decentralized Time Banking System (BlendTBS)is proposed to build a trustful, dynamic and respectful community. People in this community are encouraged to be engaged in mutual serving relationships. For this purpose, the BlendTBS is designed to reward the residents who commit in socially beneficial activities. An initial prototype is implemented on a permissioned blockchain network and a small scale study is planned to examine the utility of BlendTBS to a traditional community on the island of Aneityum, Republic of Vanuatu. Within a selected community in the village of Analgahuat, deeper insights will be explored by observing the trust enabled by Blockchain technology that allows peer to peer service exchanges between any two individuals. Authors hope this position paper may inspire more interests in the roles that blockchain technology can play in modern society.
Tropical Medicine & International Health, Jun 1, 2005
SummaryTumour necrosis factor‐alpha (TNF‐α) is one of the key cytokines that influence the pathol... more SummaryTumour necrosis factor‐alpha (TNF‐α) is one of the key cytokines that influence the pathology of microbial infections. The genetic susceptibility to severe forms of falciparum malaria is differentially associated with TNF‐α promoter gene polymorphisms (TNFP alleles). In a previous study, we identified a TNFP‐allele characterized by a C to T transition at position −857 (TNFP‐D allele) as a marker for susceptibility to cerebral malaria in Myanmar. The frequencies of TNFP alleles on six islands of Vanuatu, Melanesia (South‐west Pacific) were estimated to investigate whether malaria selection pressure on this susceptibility marker has influenced its prevalence. Within the archipelago of Vanuatu there is a decreasing cline of parasite incidence from North to South. Of the four alleles of the TNFP gene detected in Vanuatu, the TNFP‐D allele frequencies were inversely correlated with the parasite incidence of islands; TNFP‐D varied from 0.55 on the island with the lowest parasite incidence to 0.26 on the island with the highest parasite incidence (r = −0.855, P = 0.03). We also observed a significant correlation between the frequencies of α‐thalassaemia alleles, thought to protect against malaria and parasite incidence in the same populations. These data are consistent with a previously reported correspondence between the frequencies of glucose 6‐phosphate dehydrogenase (G6PD) deficiency and parasite incidences on the islands of Vanuatu (Kaneko et al. 1998) and indicate that the degree of malaria endemicity has influenced the allele frequencies of at least three loci that confer both susceptibility (TNFP‐D) and protection (α‐thalassaemias and G6PD deficiency).
A comparison of the patterns of gene flow within and between islands and the genetic diversities ... more A comparison of the patterns of gene flow within and between islands and the genetic diversities of the three species required for malaria transmission (humans, Plasmodium falciparum, and Anopheles farauti s.s.) within the model island system of Vanuatu, shows that the active dispersal of An. farauti s.s. is responsible for within island movement of parasites. In contrast, since both P. falciparum and An. farauti s.s. populations are largely restricted to islands, movement of parasites between islands is likely due to human transport. Thus, control of vectors is crucial for controlling malaria within islands, while control of human movement is essential to control malaria transmission across the archipelago.
The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has... more The human homologue of the yeast OGG1 gene, hOGG1, has been cloned, and its genetic structure has been determined. Several polymorphisms in the hOGG1 gene were detected in the Japanese populations, and among them, the Ser-Cys polymorphism at codon 326 has been shown to have a functional difference in complementation of mutant Escherichia coli that is defective in the repair of 8-hydroxyguanine. Activity in the repair of 8-hydroxyguanine is greater in hOGG1-Ser326 protein than in hOGG1(326) protein. Because many environmental carcinogens produce 8-hydroxyguanine residue and mismatching to this modified base potentially causes oncogenic mutations, the capacity to repair these lesions can be involved in cancer susceptibility in human beings. We, therefore, examined allele distributions of the Ser326Cys polymorphism in a case-control study of male lung cancer in Okinawa. The analyses based on 241 cases and 197 hospital controls disclosed the following findings. (a) Those with the Cys/Cys genotype were at an increased risk of squamous cell carcinoma and nonadenocarcinoma compared to those with the Ser/Cys and those with the Ser/Ser genotypes combined. The odds ratios adjusted for age and smoking history were 3.01 (95% confidence interval, 1.33-6.83) and 2.18 (95% confidence interval, 1.05-4.54), respectively. (b) The odds ratios for other histological subtypes of lung cancer or those in total were not significant. Those for Cys/Cys or Ser/Cys genotype against Ser/Ser did not reach statistical significance in any cell type. (c) The distributions of this polymorphism varied for different populations (Chinese, Japanese, Micronesians, Melanesians, Hungarians, and Australian Caucasians), with much less prevalence of Cys allele in the latter three populations. Although our sample size was limited, these results indicate that the Ser326Cys variant may be related to squamous cell lung cancer susceptibility. The Cys/Cys genotype appears to be more susceptible to squamous cell carcinoma, although the risk is less than that previously reported to be associated with the CYP1A1 gene. Further studies are needed to assess the importance of the interpopulation variation to cancer susceptibility.
Determinants of the use of insecticide-treated bed nets on islands of pre- and post-malaria n of ... more Determinants of the use of insecticide-treated bed nets on islands of pre- and post-malaria n of the health belief efforts when transmission continues to occur, while the results from Aneityum suggest the possibility of continued Watanabe et al. Malaria Journal 2014, 13:441
Understanding the transmission and movement of Plasmodium parasites is crucial for ma-laria elimi... more Understanding the transmission and movement of Plasmodium parasites is crucial for ma-laria elimination and prevention of resurgence. Located at the limit of malaria transmission in the Pacific, Vanuatu is an ideal candidate for elimination programs due to low endemicity and the isolated nature of its island setting. We analyzed the variation in the merozoite sur-face protein 1 (msp1) and the circumsporozoite protein (csp) of P. falciparum and P. vivax populations to examine the patterns of gene flow and population structures among seven sites on five islands in Vanuatu. Genetic diversity was in general higher in P. vivax than P. falciparum from the same site. In P. vivax, high genetic diversity was likely maintained by greater extent of gene flow among sites and among islands. Consistent with the different patterns of gene flow, the proportion of genetic variance found among islands was substan-tially higher in P. falciparum (28.81–31.23%) than in P. vivax (-0.53–3.99%). Our data s...
<p>a) Evaluation of different surface sterilization protocols. Lane 1: DNA ladder, 2: Ac, 3... more <p>a) Evaluation of different surface sterilization protocols. Lane 1: DNA ladder, 2: Ac, 3:Al, 4:Bl, 5:AlBl, 6:AlAc, 7:AcBl, 8:AlAcBl, 9,12:Extract control, 10:Alcohol, 11:Spike, 13: PCR -ve. b) Effectiveness of surface sterilization. Halite crystals (modern Saline Valley) spiked with different amounts of human DNA. Lane 1: DNA ladder, Lanes 2,3,10,11: 1.5 ng spike, Lanes 4,5,12,13: 3.0 ng spike, Lanes 6,7,14,15: 4.5 ng spike, Lanes 8,9,16,17: no spike. Lanes 2–9: no surface sterilization. Lanes 10–17 surface sterilized.</p
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Papers by J. Koji Lum