著者

Muhammad Waqar Hameed

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.14-00057, (Released:2016-03-18)

被引用文献数

2

---

Plants are frequently exposed to limitations in oxygen availability during their lifetime. During evolution, they have developed a number of physiological and morphological adaptations to tolerate oxygen and other stress conditions. These include regulation of growth by gene expression and ATP generation. The regulation of nuclear genes after hypoxia and anoxia is well studied; however, the regulation of mitochondrial genes in response to oxygen stress has not been characterized to date. Therefore, we have established an Arabidopsis mitochondrial genome-specific microarray that accommodates probes for all mitochondrial DNA-encoded genes and conserved open reading frames. Our analysis showed an up-regulation of mitochondrial transcripts in Arabidopsis roots after 48 h of hypoxia. Since no significant difference was detected in the expression of mitochondrial RNA polymerases or the mitochondrial DNA content per cell, we propose a transcriptional mode of induction of mitochondrial gene expression under hypoxia.

著者

田島 弥太郎

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.47, no.5, pp.313-314, 1972 (Released:2007-05-21)

著者

Yazaki Euki Ishikawa Sohta A. Kume Keitaro Kumagai Akira Kamaishi Takashi Tanifuji Goro Hashimoto Tetsuo Inagaki Yuji

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems

巻号頁・発行日

2017

被引用文献数

25

---

<p>All members of the order Trypanosomatida known to date are parasites that are most likely descendants of a free-living ancestor. Trypanosomatids are an excellent model to assess the transition from a free-living to a parasitic lifestyle, because a large amount of experimental data has been accumulated for well-studied members that are harmful to humans and livestock (<i>Trypanosoma</i> spp. and <i>Leishmania</i> spp.). However, recent advances in our understanding of the diversity of trypanosomatids and their close relatives (i.e., members of the class Kinetoplastea) have suggested that the change in lifestyle took place multiple times independently from that which gave rise to the extant trypanosomatid parasites. In the current study, transcriptomic data of two parasitic kinetoplastids belonging to orders other than Trypanosomatida, namely <i>Azumiobodo hoyamushi</i> (Neobodonida) and <i>Trypanoplasma borreli</i> (Parabodonida), were generated. We re-examined the transition from a free-living to a parasitic lifestyle in the evolution of kinetoplastids by combining (i) the relationship among the five orders in Kinetoplastea and (ii) that among free-living and parasitic species within the individual orders. The former relationship was inferred from a large-scale multigene alignment including the newly generated data from <i>Azumiobodo</i> and <i>Trypanoplasma</i>, as well as the data from another parasitic kinetoplastid, <i>Perkinsela</i> sp., deposited in GenBank; and the latter was inferred from a taxon-rich small subunit ribosomal DNA alignment. Finally, we discuss the potential value of parasitic kinetoplastids identified in Parabodonida and Neobodonida for studying the evolutionary process that turned a free-living species into a parasite.</p>

著者

SADAO ICHIKAWA

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.47, no.6, pp.411-421, 1972 (Released:2007-05-21)

参考文献数

12

被引用文献数

13 12

---

Somatic mutation rates from blue to pink were studied in the stamen hairs of Tradescantia ohiensis KU 7 clone, a blue/pink heterozygote, exposed to 100 to 510mR/hr gamma rays or to 12mR/hr scattering radiation. The results obtained supported the previous finding of the sensitive genetic responses of this botanical system, demonstrating that the genetic effect could be detected with this system at a radiation level as low as 3.60R total exposure (also possibly only 0.96R) given at a low exposure rate of 12mR/hr. Pooling the present and previous data, a somatic mutation rate of 3.88 or 3.43×10-4 pink mutant events per hair per R was obtained for gamma-ray irradiation during hair development. The somatic mutation rate calculated for scattering radiation was even higher than this (1.25×10-3). The doubling dose of the somatic mutations at the specific locus was calculated to be 13.8 or 15.6R when irradiated with gamma rays during hair development, and the corresponding value with scattering radiation was 4.29R. Lower doubling doses could be calculated based on published data from the stamen hairs of the same and three other Tradescantia clones irradiated more acutely. These low doubling doses seem to throw doubt on the safety standards of radiations.

著者

Marie SANDA-KAMIGAWARA Michio TOMIYAMA Sadao ICHIKAWA

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.70, no.3, pp.339-353, 1995 (Released:2004-06-24)

参考文献数

29

被引用文献数

8 10

---

The sectoring patterns of spontaneous and radiation- and EMS-induced somatic pink mutations were analyzed in the stamen hairs and petals of Tradescantia clones heterozygous for flower color (blue/pink). Spontaneous pink mutations were analyzed using clone KU 20 (a highly mutable clone especially at lower temperature) grown outdoors and clones KU 27 and BNL 02 (stable clones) grown under controlled environmental conditions, while induced pink mutations were analyzed using clones KU 27 and BNL 02 grown under the controlled environments. As for spontaneous mutations in the stamen hairs, the ratio of the number of single interstitial pink mutant events against that of single terminal pink mutant events was somewhat larger than 1 in all the three clones examined, indicating that somewhat more interstitial pink mutant events occur spontaneously than terminal pink mutant events. After treatments with X rays, gamma rays or EMS, however, the ratio increased to about 3 in the two clones examined, showing much more frequent inductions of interstitial pink mutant events than terminal pink mutant events by these mutagens. The daily changes of the sectoring patterns of radiation- and EMS-induced terminal pink mutant events in the stamen hairs showed a good accordance with the pattern of the stamen-hair development. Multiple pink mutant sectors in the same hairs were observed at much higher frequencies than expected from independent occurrences, especially in cases of spontaneous mutations in the mutable clone and of radiation-induced mutations in the two stable clones, suggesting the involvement of somatic recombinations. The sectoring patterns of radiation- and EMS-induced somatic pink mutations in the petals also showed daily changes which reflected the pattern of the flower-petal development.

著者

木村 資生

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.35, no.1, pp.7-33, 1960 (Released:2007-05-21)

参考文献数

24

被引用文献数

6 12

---

1. Definition of genetic load: Genetic load of a population in CROW'S sense (CROW 1958) refers to the amount by which population fitness is decreased through natural selection acting on genotypic differences. It may either be expressed in terms of selective values or Malthusian parameters depending on whether the continuous or discrete model is used to describe generation time (cf. KIMURA 1958).2. Kinds of genetic load: (i) Mutational load results from elimination of harmful mutations. (ii) Segregational load arises when heterotic genes (overdominance load) or a meiotic drive mechanism (distortional load) is involved. (iii) Dysmetric load, term proposed by HALDANE (unpublished), refers to a load which may be created when there is a “division of labor” between genotypes. (iv) Internal vrs. external load; The former refers to the decrease of fitness relative to the optimum genotype and thus relates to intragroup selection, while the latter refers to that relative to the optimum condition and therefore relates to intergroup selection. (v) Substitutional (evolutional load) is a cost of natural selection (cf. HALDANE, 1957) which is required in the process of substituting one allele by another through natural selection.3. Principle of minimum genetic load: This is a hypothesis that in the course of evolution important genetic parameters tend to be adjusted in such direction that the total genetic load will be minimized. More specifically, the spontaneous mutation rate and degree of dominance of mutant genes may be adjusted such that the sum of the mutational and the segregational loadL=Lm+Lewill be minimized. From this principle, the following relations may be derived (KIMURA, 1959):∑μ=0.3419E/h(1+0.3679h+…)h=0.6838√<E/2D>(1+0.0934√<E/2D>+…), where ∑μ is the spontaneous mutation rate per gamete per generation, h is the average degree (harmonic mean) of dominance in fitness of deleterious mutant genes, D is the total mutational damage or approximately the rate of inbreeding depression in fitness per unit increase in the inbreeding coefficient and E is the rate of substituion of genes in horotelic evolution (standard rate evolution, cf. SIMPSON 1944).Taking E=1/300 (cf. HALDANE 1957) and D=2 (cf. MORTON, CROW and MULLER 1956), we obtain from the above equations, h=0.0196 and ∑μ=0.0585, which agree fairly well with the corresponding observed values in Drosophila. With these values, mutational and substitutional loads (in terms of Malthusian parameters) become respectivelyLm=0.098 and Le=0.199.4. Accumulation of genetic information by natural selection: It was pointed out that the rate of accumulation of genetic information (H) by natural selection is directly proportional to the substitutional load Le, namelyH=Le/loge2≈1.44Le (bits/generation).With Le=0.199, the value obtained above, this becomes about 0.29 bits;H≈0.29.It was estimated then that the total amount of genetic information accumulated since the beginning of Cambrian epoch (500 million years) may be of the order of 108 bits, if evolution proceeded at the standard rate.Since the genetic information is transformed into phenotypic information in ontogeny, this figure (108 bits) must represent the amount of information which corresponds to the improved organization of higher animals as compared to their ancestors 500 million years back. It may also be interesting to compare this figure with the one (107_??_109 bits) obtained by ELSASSER (1958) as the probable “information content of the human organism”.

著者

Manuel Ruiz-García Pablo Orozco-terWengel Armando Castellanos Leonardo Arias

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.80, no.1, pp.57-69, 2005 (Released:2005-04-12)

参考文献数

55

被引用文献数

10 25

---

DNA samples of the spectacled bear (Tremarctos ornatus) from five Andean countries, Venezuela, Colombia, Ecuador, Peru and Bolivia, were analyzed for nine microsatellite loci. Seven of them were polymorphic, which led us to investigate several population-genetic parameters. Private alleles and significant differences in gene frequencies were found among the populations studied, which demonstrated the extent of genetic differentiation among the spectacled bear populations. The levels of gene diversity measured with these microsatellites were rather modest in this species. Hardy-Weinberg disequilibrium was especially found for the overall and the Ecuadorian samples, and might be due to the Wahl-und effect or consanguinity. Significant genetic heterogeneity was mainly observed among the Colombian and the Ecuadorian populations. Markov chain Monte Carlo simulations clearly showed that two different gene pools were present, one present in the Venezuelan-Colombian bears and other in the Ecuadorian ones.

著者

Masaru Murakami Chikako Matsuba Hideo Fujitani

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.76, no.1, pp.25-32, 2001 (Released:2002-05-31)

参考文献数

23

被引用文献数

32 41

---

The hyper-variable segments (323∼327 bp) of the mitochondrial D-loop for 169 Carassius auratus fishes in Japan were amplified by the polymerase chain reaction and the amplified products were sequenced directly and compared. A dendrogram showing three major clusters was generated with the sequence data for 37 haplotypes at 66 polymorphic sites. One cluster (cluster I) exclusively consisted of the gengorobuna, which was regarded as an independent (sub) species. The triploid ginbuna belonged to two remaining clusters, mainly in the diploid ginbuna cluster (cluster III) and partially in the goldfish cluster (cluster II). This finding suggests that the triploid ginbuna has been derived from two different maternal lineages. The triploid ginbuna was considered to have come into existence during the last ice age on the basis of this phylogenetic data. No geographic differentiation was observed with respect to the triploid ginbuna sampled at three different localities in Japan; the Shibuta River in Kanagawa, Lake Imba in Chiba and Lake Biwa in Shiga. The phylogenetic tree also demonstrated a monophyletic relationship amongst the nigorobuna, the nagabuna and the ginbuna, sharing cluster III. The nigorobuna and nagabuna populations have most likely arisen from geographic and temporal variations within the ginbuna populations. We also discuss the evolutionary origin of the triploid in view of its paternal ancestors.

著者

SADAO ICHIKAWA ICHIZO NISHIYAMA

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.42, no.3, pp.175-187, 1967 (Released:2007-05-21)

参考文献数

36

被引用文献数

2 2

---

Dry seeds of a Japanese variety of common wheat (6x), Shinchunaga, were irradiated with 10 to 40 kR of gamma rays from 60Co. No chlorophyll mutations were detected, while various kinds of morphological mutants were found in the X2 through X8 generations. About one third of the morphological mutants were found in the X2, another third in the X3, and the remaining third in the later generations.The lack of any chlorophyll mutation and the frequent occurrence of various morphological mutations are considered to indicate that there is a difference in the extent of differentiation in this polyploid plant between essential genes such as those for chlorophyll production and non-essential genes such as those determining spike length or density.Many speltoid, compactoid, squareheaded, lax-spiked and dense-spiked mutants were found, as well as various other mutants. Cytogenetical investigations were performed on these morphological mutants, and it was found that most of these morphological mutants were caused by various chromosomal aberrations, such as deficiencies, telocentrics, isochromosomes, and various aneuploid constitutions.

著者

小野 記彦

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.30, no.6, pp.269-274, 1955 (Released:2007-05-21)

参考文献数

4

---

1. ヤクシソウとワダンとの雑種は自然に存在するヤクシワダンとよばれるものもあるが, 人工的につくつた雑種もだいたいこれと同じものになる.2. この雑種の減数分裂における対合は特異であり, 染色体形態の異るにもかかわらず, 常に 5IIがみられる. その子孫においては染色体の配分がいろいろとみだされるが, 中期では5個の Configurationsを示すものがもつとも多く見られた. しかしより早い時期では, Configurations の数の減少, すなわち多価染色体が多く見られた. このようにはじめに結合していて中期に進むにつれて解消するような結合を残余対合 (residual pairing) とよんだ.3. 自然雑種は新しい種の出発点となり得るかどうかはいろいろの考えがあるが, 属間雑種のように両親の形質が遠いものでは, 二次的安定種がつくられる可能性が示された.4. ヤクシソウとアキノノゲシとの雑種では染色体数が一定しないで 10~14 のいろいろの数の細胞が一つの根においてもキメラになつているのがみとめられた. しかしその中で12のものが, もつとも多く, しかも得られた9個体において, このことは常に一定であつた.5. 同じような染色体の分断消失による減少はヤクシソウとアゼトウナとの雑種, ワダンとアキノノゲシとの雑種においても見出される. しかもいつでも分断消失する染色体は父方のものである.6. 自然にもこのような雑種がみられるが, アゼトウナ自然集団の中から採集された自然雑種においても同じように染色体の分断消失がみられる.7. 自然集団の中には 90% 以上の高い稔性のもののみの集団と 20% ぐらいのひくい稔性のものをふくむ集団とがある. 前者は古くできた雑種集団であり, 後者は新しくできた雑種のふくまれる集団であると思われる.

著者

Yukihide Abe Atsushi Hoshino Shigeru Iida

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.72, no.2, pp.57-62, 1997 (Released:2002-12-03)

参考文献数

22

被引用文献数

7 13

---

The speckled mutant of the Japanese morning glory blooms pale yellow flowers with fine and round colored spots, or speckles, distributed over the corolla. Since it also occasionally produces flowers with colored sectors apparently due to somatic mutations, the mutable speckled allele is thought to carry a transposable element. In this paper, we show that the appearance of the variegation phenotypes in the speckled mutant was controlled not only by the recessive speckled allele but also by a dominant genetic element, termed speckled-activator. Our results also indicated that the recessive c-1 mutation affecting pigmentation of flowers and mapped near the speckled locus causes a defect in a regulatory gene controlling the expression of structural genes for anthocyanin biosynthesis.

著者

Aoki Wataru Watanabe Maiko Watanabe Masaki Kobayashi Naoki Terajima Jun Sugita-Konishi Yoshiko Kondo Kazunari Hara-Kudo Yukiko

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.95, no.3, pp.133-139, 2020

被引用文献数

3

---

<p><i>Entoloma sarcopum</i> is widely known as an edible mushroom but appears morphologically similar to the poisonous mushrooms <i>E. rhodopolium</i> sensu lato (s. l.) and <i>E. sinuatum</i> s. l. Many cases of food poisoning caused by eating these poisonous mushrooms occur each year in Japan. Therefore, they were recently reclassified based on both morphological and molecular characteristics as sensu stricto species. In this study, we analyzed the nucleotide sequences of the rRNA gene (rDNA) cluster region, mainly including the internal transcribed spacer regions and mitochondrial cytochrome oxidase 1 (CO1) gene, in <i>E. sarcopum</i> and its related species, to evaluate performances of these genes as genetic markers for identification and molecular phylogenetic analysis. We found that the CO1 gene contained lineage-specific insertion/deletion sequences, and our CO1 tree yielded phylogenetic information that was not supported by analysis of the rDNA cluster region sequence. Our results suggested that the CO1 gene is a better genetic marker than the rDNA cluster region, which is the most widely used marker for fungal identification and classification, for discrimination between edible and poisonous mushrooms among Japanese <i>E. sarcopum</i> and related species. Our study thus reports a new genetic marker that is useful for detection of Japanese poisonous mushrooms, <i>Entoloma</i>.</p>

著者

Satoshi Ishishita Yoichi Matsuda

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.16-00022, (Released:2016-09-15)

被引用文献数

6

---

Hybrid incompatibility is important in speciation as it prevents gene flow between closely related populations. Reduced fitness from hybrid incompatibility may also reinforce prezygotic reproductive isolation between sympatric populations. However, the genetic and developmental basis of hybrid incompatibility in higher vertebrates remains poorly understood. Mammals and birds, both amniotes, have similar developmental processes, but marked differences in development such as the XY/ZW sex determination systems and the presence or absence of genomic imprinting. Here, we review the sterile phenotype of hybrids between the Phodopus dwarf hamsters P. campbelli and P. sungorus, and the inviable phenotype of hybrids between two birds of the family Phasianidae, chicken (Gallus gallus domesticus) and Japanese quail (Coturnix japonica). We propose hypotheses for developmental defects that are associated with these hybrid incompatibilities. In addition, we discuss the genetic and developmental basis for these defects in conjunction with recent findings from mouse and avian models of genetics, reproductive biology and genomics. We suggest that these hybrids are ideal animal models for studying the genetic and developmental basis of hybrid incompatibility in amniotes.

著者

星野 安咨

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.16, no.4, pp.155-163, 1940 (Released:2007-04-04)

参考文献数

4

被引用文献数

3

---

In this report two more rare pattern types: aulica (Fig. 1-a, b) and gutta (new name proposed by Prof. T. Komai) (Fig. 1-f, g, h) are dealt with. Both of these are due to the factors (PAu=factor for aulica, PG=factor for gutta) belonging to the same allelomorphic series as conspicua, transversifascia, spectabilis, axyridis, forficula and succinea and behave as dominants to succinea.The heterozygote of axyridis and aulica (PAPAu) (Fig. 1-c) and the heterozygote of forficula and aulica (PFPAu) (Fig. 1-d) can be distinguished as such from homozygotes. The heterozygote of transversifascia and aulica (PTPAu) may be distinguished from transversifascia in that the spot has a concavity on the antero-median side (Fig. 1-e), though in some cases the heterozygote of transversifascia and aulica shows the same appenrance as transversifascia. The distinction between the heterozygote of gutta and axyridis (PGPA) and the heterozygote of conspicus and axridis (PCPA) and that between the heterozygote of gutta and forficula (PGPF) and the heterozygote of conspicua and forficula (PCPF) can often made by the fact that the spot is provided with an accessory speck on its antero-median corner, though the speck may be missing in some cases (see Report II, Fig. 1-l, m and Report III, Fig. 1-e). The heterozygote of conspicua and aulica (PCPAu), the heterozygote of conspicua and gutta (PCPG), the heterozygote of gutta and spectabilis (PGPS), the heterozygote of gutta and transversifascia (PGPT) and the heterozygote of gutta and aulica (PGPAu) can not be distinguished from conspicua; the heterozygote of spectabilis and aulica (PSPAu) may shows the same appearance as spectabilis.

著者

Masami HASEGAWA

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.65, no.4, pp.243-266, 1990 (Released:2006-06-10)

参考文献数

85

被引用文献数

11 21

---

Statistical methods for estimating the branching order and the branching dates from DNA sequence data, taking into account of the rate variation among lineages, are reviewed. An application of the methods to data from primates suggests that chimpanzee is the closest relative of man, and further suggests that these two species diverged about 4-5 million years ago.

著者

Xin Liu Hua Wang Guang Li Hui-Zhe Huang Yi-Quan Wang

出版者

日本遺伝学会

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.88, no.4, pp.261-269, 2013 (Released:2014-01-25)

参考文献数

25

被引用文献数

2 10

---

Vertebrate Pax1 gene is a member of Pax gene family and encodes a transcription factor associated with crucial roles in the development of pharyngeal pouch, scletrotome and limb bud. In zebrafish, the genome contains two Pax1 paralogs, DrPax1a and DrPax1b, which share high sequence similarity with other Pax1 genes. To elucidate the function of zebrafish DrPax1b gene, we first examined the gene expression pattern and found that it was mainly expressed in the endodermal pharyngeal pouch, caudal somites, notochord, and fin bud. Then, we performed knockdown experiments using antisense morpholino oligonucleotides, which lead to the defects in the vertebral column, tail, pharyngeal skeleton, and pectoral fin. Additionally, we also found that the mouse MmPax1 mRNA, but not the amphioxus AmphiPax1/9 mRNA, could rescue the MO-induced defects. Furthermore, sequence alignment revealed that the N-terminal region of vertebrate Pax1 and amphioxus Pax1/9 were highly conserved, whereas their C-terminal regions were relatively divergent. However, the chimeric Am(N)Dr(C)Pax1, Mm(N)Dr(C)Pax1 and Dr(N)Mm(C)Pax1 mRNA could partially rescue the defects, while the Dr(N)Am(C)Pax1 mRNA could not. In conclusion, our data demonstrate a conserved function of DrPax1b in the development of the vertebral column, pectoral fin and pharyngeal skeleton formation in zebrafish and also provide critical insight into the functional evolution of Pax1 gene by changing its C-terminal sequence.

著者

芳賀 〓

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.29, no.5-6, pp.228-234, 1954 (Released:2007-11-30)

参考文献数

20

被引用文献数

3 1

著者

平井 久男

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.31, no.2, pp.54-64, 1956 (Released:2007-05-21)

参考文献数

84

被引用文献数

4 4

---

脉翅目のヒロバカゲロウ上科 (Osmyloidea) に属する3科9種の染色体研究を行い, 系統的関係について論及した. 染色体数, 性染色体の型は Table 1 に示した通りである.カマキリモドキ科 (Mantispidae) においては1対の巨大な常染色体が存在し, これがこの科の特徴となつている.ミズカゲロウ (Sisyra japonica) のX-Y染色体の第一分裂における先行現象は他種の場合に比し著しくない. ツマモンヒロバカゲロウ (Plethosmylus decoratus) は X1 X2-Y 型の複合性染色体をもつている.X-Y染色体の行動を成長期の核内に追求した. XとYとは肥厚期 (diakinesis) の時期にすでに接合をといて分離していることがたしかめられた. 細長期 (leptotene) から合体期 (pachytene) にかけてX-Y染色体は異常凝縮をなした3部構造をしているが, 二重期(diplotene) になると染色性が一時弱まり, 肥厚期 (diakinesis) に入つてXとYとは分離する.

著者

岸本 艶

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.17, no.6, pp.310-321, 1941-12-31 (Released:2011-03-14)

著者

大西 近江 長久保 有之

出版者

日本遺伝学会

雑誌

遺伝学雑誌 (ISSN:0021504X)

巻号頁・発行日

vol.57, no.6, pp.641-650, 1982

被引用文献数

3 5

---

Allelism tests among 15 independently established dwarf lines revealed that five loci are involved in dwarfism in common buckwheat. They are designated dwA, dwB, dwC, dwD and dwE. The frequencies of dwarf mutants at four loci, dwA, dwB, dwC and dwD were investigated in three Japanese populations, Iwate, Togakushi, Higashi-Iyayama, by using four representative homozygous lines as the testers. The frequencies varied slightly among the populations, but on the average they were 0.235%, 0.067%, 0.294% and 0.196% for the dwA, dwB, dwC and dwD loci, respectively. These low allele frequencies imply that the recurrent mutation is balanced by selection against the dwarf alleles. This conclusion was confirmed by supplemental data on the frequency of dwarf mutants per gamete and a field survey of dwarf homozygotes in randomly mating populations in farmer&prime;s field. Approximately 0.50% of the gametes contain a dwarf allele, whereas the incidence of dwarfism in the randomly mating populations was only 4.25 &times;10^-6. The latter estimate was based on a study of more than 3 million plants.