• 제목/요약/키워드: Natural and experimental populations

검색결과 24건 처리시간 0.027초

자연과 실험집단내 Drosophila melanogaster 제 2 염색체의 유전적 변이성에 대한 비교 연구 (Comparative Studies on Genetic Variabilities of Second Chromosomes in Sasang Natural and Experimental Populations of Drosophila melanogaster)

  • 손성곤;최영현;이원호
    • 한국환경과학회지
    • /
    • 제3권4호
    • /
    • pp.297-304
    • /
    • 1994
  • The genetic variabilities of second chromosomes concealed Sasang natural and experimental populations of Drosophila melanogaster have been analyzed. The experimental population was composed of D. melanognter which had the lethal-free second chromosome collected from Sasang natural population in 1982. The results were as follow; The mean frequencies of deleterious genes were estimated % be 33.33% in Sasang natural population and 31.72% in experimental population. The allelism rates in lethal genes isolated from the natural and experimental populations were calculated to be about 0.95% and 12.28%, respectively. The allelism rates between lethal genes isolated from the natural population and those of the experimental population were calculated to be about 0.01%. The mean values of elimination by frequencies of deleterious genes and allelism rates were 0.0011 in the natural population and 0.0124 in the experimental population. The frequencies of phenotypic sterility of males in the natural and experimental populations were estimated to be 1.49% and 1.36%, respectively. The frequencies of genotypic sterility of females and males were estimated to be 0.90% and 1.80% in the natural population, and that of males was 2.38% in the experimental population.

  • PDF

Drosophila melanogaster 자연 및 실험집단내의 유해유전자 분석 (Analysis of deleterious genes in natural and experimental populations of Drosophila melanogaster)

  • 이원호;최우영;권은전;박희정
    • 생명과학회지
    • /
    • 제13권3호
    • /
    • pp.252-257
    • /
    • 2003
  • 인가성 종인 노랑 초파리의 제2염색체를 대상으로, 자연집단과 장기 유지시켜온 실험집단의 생존도 관련 유해유전자의 빈도를 조사하였다. 2년간 연속 조사한 부산 일원 자연집단내의 치사 및 반치사를 포함한 유해유전자의 빈도는 약 14.3∼25.4% 정도로서 년도 의존적 불안정 변이를 보인 반면 집단 형성 후 약 6570일과 약 7300일째의 실험집단내의 동 빈도는 약 26.5∼27.2% 정도로서 매우 안정적인 변이를 나타내고 있었다. 치사유전자 보유 염색체를 대상으로한 동좌율 조사에서는 자연집단에서 0.76%의 낮은 비율인데 반하여 실험집단에서는 9.76∼14.17%의 높은 동좌 비율을 보였다. 완전 정상 유전자 보유 계통만으로 형성, 장기 유지시켜온 실험집단내의 치사유전자의 유발과 축적은 세대를 거듭함에 따라 자연 돌연변이에 의해 6570일 현재 약 14.5%의 안정적 빈도를 보여주었다. 집단 내 치사 유전자의 동형접합체화로 인한 집단 내에서의 제거율은 6570일 현재 약 0.0106 정도이며, 이로부터 환산되는 실험집단내의 유효크기는 약 430개체 정도였다.

Experimental Techniques for Evaluating the Success of Restoration Projects

  • Robinson, George R.;Handel, Steven-N.l;Mattei, Jennifer
    • The Korean Journal of Ecology
    • /
    • 제25권1호
    • /
    • pp.1-7
    • /
    • 2002
  • The ecological background of a restoration project is complex and difficult to betermine without experimentation. A useful context for experiments is the well-studied process of natural succession, because the factors that drive or inhibit succession are also at work during reclamation (a form of primary succession) and restoration (which often resembles secondary succession). Using experimental studies on urban wasteland reclamation, we have tested for factors that stimulate or inhibit succession during early phases of woodland development in the Northeastern United states. The emphasis has been on mutualisms (seed dispersal, pollination, and mycorrhizae) and microsite limitations in the recruitment, growth, and reproduction of woody plants. Using plantings of seeds, seedlings, and clusters of reproductively mature plants on abandoned landfills, we have observed that (1) soil microsite deficiencies lead to very poor germination (<0.1$\%$) and seedling survival (<0.01$\%$) of most native species; (2) seed dispersal by birds is a significant and reliable source of woody plant recruitment; however (3) proximity effects are strong, with most (up to 95$\%$) of seed rain falling in the vicinity of planted clusters that are closest to putative seed sources; and (4) remnant natural woodlands are critical components of the recruitment process. To emphasize the last point, in one case, we found that the destruction of approximately 50$\%$ of nearby natural woodland vegetation led to a commensurate decline in seed rain. In another case, we found that the species richness of recruits was strictly limited by the species composition of nearby source plant communities, with no evidence of community enrichment by long distance dispersal over 5 years. We conclude from these results that the size and proximity of remnant natural populations are critical considerations when planning reclamation and restoration programs that rely on natural successional processes.

Drosophila auraria 의 반문다형현상의 유전학적분석 (Genetic Analysis of the Polymorphism of Color Pattern in Drosophila auraria)

  • 이택준
    • 한국동물학회지
    • /
    • 제7권2호
    • /
    • pp.41-47
    • /
    • 1964
  • D.auraria is a species belonging to the D.melanogaster group, and this species was divided into 3 races(A, B and C race ) by morphoogical difference of the genitals . Korean populations of D.auraria A race are polymorphic with respect to the pigmentation of the abdominal tergites. The female shows two forms of color pattern, dark and light, on the sixth to the ninth tergites, and the male has no distinction shown by the female. Crossing experiments in the laboratory have shown that the difference between these color forms is due to a single pair of allelic genes located on an autosome. In natural populations, the light forms of females are always commoner than the dark one. The number of the light form increases relatively in southern localities and decreases relatively in northern localities. Furthermore, the number of the light form increases relatively in summer and decreases relatively in fall and spring. By genetic analyses of these wild flies, the relation, d/d>d/D>D/D has been disclosed as regards the relative frequencies of the genotypes in natural populations. Three experimental populations have been set up in the laboratory. Homozygous dark forms and homozygous light forms were mixed together and cultured in population cage at the temperature of 25 $^{\circ}C$. Approximately one year later, the frequencies of the light and the dark forms reached an equilibrium , the light one being usually more frequent than the dark one. This indicates that the heterozygous dark form possesses the highest adaptive value, the homozygous light being intermediate and the homozygous dark lowest. In number of adults hached, the homozygous light form was superior to the heterozygous dark form and the homozygous dark form, but the differences are scarcely significant.

  • PDF

Co-Evolutionary Algorithm for the Intelligent System

  • Sim, Kwee-Bo;Jun, Hyo-Byung
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1999년도 하계종합학술대회 논문집
    • /
    • pp.1013-1016
    • /
    • 1999
  • Simple Genetic Algorithm(SGA) proposed by J. H. Holland is a population-based optimization method based on the principle of the Darwinian natural selection. The theoretical foundations of GA are the Schema Theorem and the Building Block Hypothesis. Although GA does well in many applications as an optimization method, still it does not guarantee the convergence to a global optimum in GA-hard problems and deceptive problems. Therefore as an alternative scheme, there is a growing interest in a co-evolutionary system, where two populations constantly interact and co-evolve. In this paper we propose an extended schema theorem associated with a schema co-evolutionary algorithm(SCEA), which explains why the co-evolutionary algorithm works better than SGA. The experimental results show that the SCEA works well in optimization problems including deceptive functions.

  • PDF

건강관리 프로그램이 노인의 건강관리에 미치는 영향 (Effect of a Health Management Program on Health Promotion in the Elderly)

  • 김선엽;강회양
    • 한국전문물리치료학회지
    • /
    • 제5권2호
    • /
    • pp.47-64
    • /
    • 1998
  • The purposes of this research were to understand the realities of health management and to analyze the subjective, functional, psychological, and social health effects of the application of an exercise and education program to manage health on an elderly population residing in an agricultural community. The specific purposes of this research were: 1. to determine the subjective, functional, psychological health conditions, and performance level of instrumental activities of daily living of both the experimental and control groups before introducing a health management program, and then 2. to compare these with both the experimental and control groups' subjective, functional, psychological health condition and performance level of instrumental activities of daily living after applying the health management program. The health management program was introduced to the experimental group (50 people) but not to the control group (50 people). The health management program was composed of a health exercise program and a health education program. A comparative study of subjective health conditions was done to examine the effect of the health management program and the characteristics of health related variables before and after the program application. The results were as follows: 1. When the experimental group, which had received the 8-week health management exercise and education program, was compared with the control group, which had not, the experimental group's subjective health condition scored higher than that of the control group (p

  • PDF

CRISPR/Cas9-mediated knockout of CD47 causes hemolytic anemia with splenomegaly in C57BL/6 mice

  • Kim, Joo-Il;Park, Jin-Sung;Kwak, Jina;Lim, Hyun-Jin;Ryu, Soo-Kyung;Kwon, Euna;Han, Kang-Min;Nam, Ki-Taek;Lee, Han-Woong;Kang, Byeong-Cheol
    • Laboraroty Animal Research
    • /
    • 제34권4호
    • /
    • pp.302-310
    • /
    • 2018
  • CD47 (integrin-associated protein), a multi-spanning transmembrane protein expressed in all cells including red blood cells (RBCs) and leukocytes, interacts with signal regulatory protein ${\alpha}$ ($SIRP{\alpha}$) on macrophages and thereby inhibits phagocytosis of RBCs. Recently, we generated a novel C57BL/6J CD47 knockout ($CD47^{-/-}$ hereafter) mouse line by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease, and here report their hematological phenotypes. On monitoring their birth and development, $CD47^{-/-}$ mice were born viable with a natural male-to-female sex ratio and normally developed from birth through puberty to adulthood without noticeable changes in growth, food/water intake compared to their age and sex-matched wild-type littermates up to 26 weeks. Hematological analysis revealed a mild but significant reduction of RBC counts and hemoglobin in 16 week-old male $CD47^{-/-}$ mice which were aggravated at the age of 26 weeks with increased reticulocyte counts and mean corpuscular volume (MCV), suggesting hemolytic anemia. Interestingly, anemia in female $CD47^{-/-}$ mice became evident at 26 weeks, but splenomegaly was identified in both genders of $CD47^{-/-}$ mice from the age of 16 weeks, consistent with development of hemolytic anemia. Additionally, helper and cytotoxic T cell populations were considerably reduced in the spleen, but not in thymus, of $CD47^{-/-}$ mice, suggesting a crucial role of CD47 in proliferation of T cells. Collectively, these findings indicate that our $CD47^{-/-}$ mice have progressive hemolytic anemia and splenic depletion of mature T cell populations and therefore may be useful as an in vivo model to study the function of CD47.

소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(III) -주왕산(周王山), 안면도(安眠島), 오대산(五臺山) 소나무집단(集團)의 차대(次代)의 유전변이(遺傳變異)- (The Variation of Natural Population of Pinus densiflora S. et Z. in Korea (III) -Genetic Variation of the Progeny Originated from Mt. Chu-wang, An-Myon Island and Mt. O-Dae Populations-)

  • 임경빈;권기원
    • 한국산림과학회지
    • /
    • 제32권1호
    • /
    • pp.36-63
    • /
    • 1976
  • 1974년(年) 천연(天然)소나무집단(集團)에 대한 유전적변이(遺傳的變異)를 분석(分析)하고져 먼저 경북(慶北) 청송군(靑松郡) 소재(所在) 주왕산(周王山)소나무림(林), 충남(忠南) 서산군(瑞山郡) 소재(所在) 안면도(安眠島) 소나무림(林), 그리고 강원도(江原道) 평창군(平昌郡) 소재(所在) 소나무림(林)을 대상(對象)으로하여 각(各) 집단(集團)에서 되도록 소면적(小面積)의 범위내(範圍內)에 서있는 소나무 개체(個體)를 각(各) 20주(株)씩 총 60주(株)를 택(擇)하여 그 모수(母樹)에 대한 형태학적(形態學的) 특성(特性)등을 조사측정(調査測定)하고 집단간(集團間)에 보이는 차이(差異) 그리고 한 집단내(集團內)에 있는 각개체수목(各個體樹木)의 형질(形質)을 조사보고(調査報告)한바 있다(제일보고문(第一報論文). 1974년(年) 가을에 가계별(家系別)로 종자(種字)을 채취(採取)하여서 가계별(家系別) 및 산지별(産地別)의 차이(差異)를 분석(分析)하고 동시(同時)에 그 종자(種字)를 파종하여서 1-0묘(苗) 및 1-1묘(苗)를 대상(對象)으로 생장인자(生長因子)에 대한 측정(測定)을 하고 그 유전력(遺傳力)을 계산(計算)해 보았다. 그밖에 엽록소함량(葉綠素含量) 또는 monoterpene등의 함량(含量)의 차이(差異)를 분석(分析)해 보았다. 종자(種字)의 형태학적(形態學的) 특성(特性)에 있어서는 집단간(集團間) 또 가계간(家系間)에 유의차(有意差)를 보이지 않는 것도 있었으나 대체(大體)로 유의차(有意差)가 인정(認定)되었다. 그리고 각형질간(各形質間)의 상관(相關)을 보았는데 구과폭(毬果幅)과 종자익(種字翼)의 폭(幅), 구과장(毬果長)과 종자익(種字翼)의 길이간(間), 그리고 구과(毬果) 생중량(生重量)과 종자중량간(種字重量間)에는 정(正)의 상관(相關)이 보였다. 묘고(苗高)와 근원경(根元徑)의 성장(成長)에 있어서는 가계간(家系間) 그리고 집단간(集團間)에 차이(差異)가 인정되었다. 묘고(苗高)의 유전력(遺傳力)은 집단(集團)의 평균치(平均値)를 가지고 분석(分析)하였다. 즉 집단(集團)에 관계(關係)되는 분산(分散)을 유전분산(遺傳分散)으로 보고서 유전력(遺傳力)을 계산(計算)해 보았는데 1-0묘(苗)의 묘고(苗高)에서는 0.29, 1-1묘(苗)에서는 0.14가 그리고 근원경(根元徑)에 있어서는 1-0묘(苗)는 0.15, 1-1묘(苗)에서는 0.06이였다. 기공열수(氣孔列數)에 있어서는 집단간차이(集團間差異)가 있었으나 거치밀도(鋸齒密度)에는 차이(差異)가 없었다. 침엽(針葉)의 특성(特性)에 관(關)해서는 모수(母樹)와 차대간(次代間)에 상관(相關)이 없었다. 엽록소함량(葉綠素含量)은 집단간차이(集團間差異)는 보였으나 가계간차이(家系間差異)는 없었다. monoterpene의 성분(成分)에 있어서는 myrcene과 ${\beta}$-phellandrene의 함량(含量)으로 집단차(集團差)를 볼 수 있었다.

  • PDF

Landscape Ecological Studies on Structure and Dynamics of Plant Populations on Vegetation-Landscape Patterns in Rural Regions: I. The Effect of Patch Shape on the Initial Population Structure of Pine and Oaks

  • Rim, Young-Deuk;Hong, Sun-Kee
    • The Korean Journal of Ecology
    • /
    • 제22권2호
    • /
    • pp.69-77
    • /
    • 1999
  • Secondary vegetation. the holistically integrated system of nature and human being, is the complicated ecosystem that is composed of natural and man-created factors. Understanding the ecological function of secondary vegetation supplies us many important informations for sustainable landscape management and ecological restoration planning. In this research, we tried to examine the shape effect of vegetation patch on early structure of populations of pine and oaks. Moreover. we also tried to clarify the ecological functions of patch edge by exploring the patch effect on germination using patch index. In addition, we present the landscape structure of man -made vegetation of our study area, and setting experimental design of research. Vegetation landscape of study area is typical human disturbed landscape mainly composed of disturbance patches. Vegetation types of graveyard and managed pine forest were controlled by periodically repeated management. However, current seedlings of pine occurred well at both vegetation types. Presence of both saplings were more controlled in managed pine forest (PDM) and graveyard (G) than those of undergrowth (PD) and forest edge (FE) with canopy trees. The number of pine seedlings increased with patch size and patch perimeter. That of oak seedlings was, however, not significantly different. Larger graveyards provided higher light availability for germination of pine seedlings. We think, however, most seedlings of both species in the large sized graveyards without shade will die more easily than that of small sized ones before rainy summer. Relationships between patch shape and germination of two woody species cannot be exactly explained enough yet in these results. More informations on spatial interaction of the total species with differently sized patches are necessary to solve the concept of patch effect on species colonization.

  • PDF

Genetic associations between ADHD and dopaminergic genes (DAT1 and DRD4) VNTRs in Korean children

  • Hong, Jun Ho;Hwang, In Wook;Lim, Myung Ho;Kwon, Ho Jang;Jin, Han Jun
    • Genes and Genomics
    • /
    • 제40권12호
    • /
    • pp.1309-1317
    • /
    • 2018
  • It is well known that dopaminergic genes affect the development of attention deficit hyperactivity disorder (ADHD) in various populations. Many studies have shown that variable number tandem repeats (VNTRs) located within the 3′-untranslated region of DAT1 and in exon 3 of DRD4 are associated with ADHD development; however, these results were inconsistent. Therefore, we investigated the genetic association between two VNTRs and ADHD in Korean children. We determined the VNTRs using PCR. We examined genotype and allele frequency differences between the experimental and control groups, along with the odds ratios, using Chi square and exact tests. We observed a significant association between the children with ADHD and the control group in the 10R/10R genotype of DAT1 VNTRs (p=0.025). In addition, the 11R allele of DAT1 VNTRs showed a higher frequency in the control group than in the ADHD group (p=0.023). Also, the short repeat (without 11R) and long repeat alleles (including 11R) were associated with ADHD (p<0.05). The analysis of DRD4 VNTRs revealed that the 2R allele is associated with ADHD (p=0.025). A significant result was also observed in long and short repeats (p<0.05). Additionally, ADHD subtypes showed that the DRD4 VNTRs are associated with combined and hyperactive-impulsive subtype groups (p<0.05). Therefore, our results suggest that DAT1 VNTRs and DRD4 VNTRs play a role in the genetic etiology of ADHD in Korean children.