HYBRIDIZATION OF TRITICUM AND AGROPYRON: II. CYTOLOGY OF THE MALE PARENTS AND F1 GENERATION

1936 ◽  
Vol 14c (5) ◽  
pp. 203-214 ◽  
Author(s):  
F. H. Peto
Keyword(s):  
Genetic Factors ◽  
Alternative Explanation ◽  
Chromosome Doubling ◽  
Genetic Constitution ◽  
Tetraploid Species ◽  
Pairing Behavior ◽  
Partial Homology ◽  
F1 Generation

Meiosis was studied in A. glaucum (2n = 42), A. elongatum (2n = 70), and in the F1 of these species crossed on varieties of T. dicoccum, T. durum and T. vulgare. In A. glaucum a large proportion of the chromosomes formed bivalents with occasional univalents and quadrivalents. A. elongatum was very unusual in that uni-, bi-, tri-, quadri-, quinqui-, sexa-, and octavalent configurations were observed. With one exception the A. glaucum × Triticum hybrids averaged 4.8–6.2 bivalents per nucleus, thus indicating partial homology between one set of chromosomes from each of the parents. In the A. elongatum × Triticum hybrids, numerous multivalent configurations were observed and it was concluded that auto- as well as allosyndesis had occurred. Approximately one set of chromosomes remained unpaired in one collection of T. dicoccum var. Vernal × A. elongatum and approximately two sets remained unpaired in crosses between three varieties of T. vulgare and A. elongatum.Two of the crosses exhibited an abnormally small amount of pairing, an effect most plausibly attributed to the reaction of genetic factors limiting prophase pairing.Tentative conclusions have been made regarding the origin and genetic constitution of A. elongatum from the pairing behavior of the chromosomes in this species and its hybrids. It appears likely that A. elongatum arose through hybridization between hexaploid and tetraploid species of Agropyron with subsequent chromosome doubling. An alternative explanation is also suggested.

scholarly journals INDICATIONS OF TISSUE SPECIFICITY IN A TRANSPLANTABLE SARCOMA

1924 ◽  
Vol 39 (3) ◽  
pp. 447-456 ◽  
Author(s):  
Leonell C. Strong
Keyword(s):  
Growth Rate ◽  
Tissue Specificity ◽  
Genetic Factors ◽  
Genetic Constitution ◽  
Genetic Origin ◽  
Transplanted Tumor

1. A sarcoma of the mouse which has proved to be transplantable to a great variety of strains of mice does not furnish an exception to the theory that transplantability is controlled by genetic factors, since this tumor possesses some characteristics that are more than probably genetic. 2. The phenomenon of the assumption of tissue specificity on the part of the host may possibly be of genetic origin. 3. The evidence suggests that the gonads have some influence on the assumption of tissue specificity on the part of the host. 4. The growth rate of the transplanted tumor may possibly be correlated with the genetic constitution of the host.

Neurosis and Experimental Psychology

1958 ◽  
Vol 104 (434) ◽  
pp. 55-62 ◽  
Author(s):  
H. Gwynne Jones
Keyword(s):  
Environmental Stress ◽  
Experimental Psychology ◽  
Genetic Factors ◽  
Genetic Constitution ◽  
Behavioural Disturbance ◽  
The Individual

Genetic factors have been shown to play an important role in the development of neurosis. These factors, however, determine the vulnerability of an individual, the degree of his predisposition for neurotic breakdown, while the available evidence indicates that the actual behavioural disturbance results from the imposition of some form of environmental stress on the individual concerned. The probability that any particular individual will develop a neurosis is partly determined by his genetic constitution and partly by the degree of stress to which he is subjected.

scholarly journals Inheritance of mature leaf properties in grapevine progeny obtained by crossing Muscat Hamburg and Villard Blanc cultivars

2015 ◽  
Vol 60 (2) ◽  
pp. 169-176
Author(s):  
Dragan Nikolic
Keyword(s):  
Genetic Factors ◽  
Leaf Size ◽  
Mature Leaf ◽  
Hybrid Progeny ◽  
Lower Side ◽  
General Shape ◽  
Blade Number ◽  
Inheritance Mode ◽  
Progeny Size ◽  
F1 Generation

and inheritance mode of six properties of the mature leaf (size of blade, number of lobes, shape of teeth, general shape of petiole sinus, density of prostrate and erect hairs between veins on the lower side of blade) were analyzed in 90 seedlings of the F1 generation from the crossing combination of Muscat Hamburg x Villard Blanc. The properties analyzed were classified according to the OIV system of classification and ?2 test was used to determine the inheritance mode. A substantial variability of the analyzed characteristics was recorded in the hybrid progeny. Size of blade, number of lobes, shape of teeth and general shape of petiole sinus were most probably affected by a great number of genetic factors. Monogenic inheritance was determined with regard to the density of prostrate and erect hairs between veins on the lower side of blade.

CYTOLOGICAL STUDIES IN ALFALFA POLYPLOIDS

1954 ◽  
Vol 32 (4) ◽  
pp. 531-542 ◽  
Author(s):  
J. M. Armstrong
Keyword(s):  
Chiasma Frequency ◽  
Diploid Species ◽  
Low Frequency ◽  
Morphological Characters ◽  
Tetraploid Species ◽  
Meiotic Behavior ◽  
Meiotic Irregularities ◽  
Medicago Sativa L ◽  
Partial Homology ◽  
Quadrivalent Frequency

Normal tetraploid alfalfa, Medicago sativa L., is characterized by meiotic irregularities consisting of a low percentage of univalents, trivalents, and quadrivalents. While these irregularities might suggest an autoploid origin, their frequency is too low to be conclusive. Cytological studies of the induced octoploid and of the hexaploid, obtained from crossing tetraploid and octoploid, indicate that the two genomes in the tetraploid are only partially homologous. The partial homology is established by the meiotic behavior in the hexaploid in which a low univalent frequency indicates fairly complete pairing between the A and B genomes. The comparatively low frequency of quadrivalents in the octoploid indicates a correspondingly low chiasma frequency at pachytene. Nevertheless this quadrivalent frequency in the octoploid is more than three times as high as in the tetraploid which suggests a lack of complete homology between the two genomes. The theory is advanced that tetraploid species of Medicago originated from crosses between a series of diploid species fairly similar cytologically but differing in well marked, morphological characters. This affords an explanation for the inheritance of some characters in a disomic and others in a tetrasomic manner. Cytological and genetic evidence thus points to tetraploid alfalfa as originating as an alloploid from closely related diploid species.

scholarly journals SERT and BDNF polymorphisms interplay on neuroticism in borderline personality disorder

2020 ◽  
Author(s):  
Valeria Salinas ◽  
Juana Villarroel ◽  
Hernán Silva ◽  
Luisa Herrera ◽  
Sonia Jerez ◽  
...  
Keyword(s):  
Borderline Personality Disorder ◽  
Personality Disorder ◽  
Personality Traits ◽  
Genetic Factors ◽  
Borderline Personality ◽  
Genetic Constitution ◽  
Bdnf Gene ◽  
Bdnf Val66met Polymorphism ◽  
S Allele ◽  
The Brain

Abstract Objective Genetic factors underlying different personality traits are not entirely understood, particularly how genes interact to modulate their effect. We studied 76 patients diagnosed with borderline personality disorder (BPD), characterized by extreme levels of personality traits, especially neuroticism (N), in which we genotyped two polymorphisms, the 5HTTLPR of the Serotonin transporter (SERT) gene, and the Val66Met of the Brain-derived neurotrophic factor (BDNF) gene. Results We found an association with SERT, where S-allele carriers had significantly higher levels of N than L-homozygous. Furthermore, we found that the protective effect of L-homozygosity is only evident on A-allele carriers of the BDNF Val66Met polymorphism. Genetic constitution in SERT and BDNF seems to be important in neuroticism, the most relevant personality trait on BPD.

scholarly journals Genetic factors controlling the proliferative activity of mouse epidermal melanocytes during the healing of skin wounds.

Genetics ◽  
1988 ◽  
Vol 120 (2) ◽  
pp. 551-558
Author(s):  
T Hirobe
Keyword(s):  
Proliferative Activity ◽  
Genetic Basis ◽  
Genetic Factors ◽  
Skin Wounds ◽  
Wound Edge ◽  
Newborn Mice ◽  
Healing Of Skin Wounds ◽  
The Difference ◽  
F2 Generation ◽  
F1 Generation

Abstract A cut was made on the middorsal skin of newborn mice of strains C57BL/10J, C57BL/10J-A/A, and C3H/He using fine iridectomy scissors. In the epidermis within 1 mm of the wound edge in C57BL/10J and C57BL/10J-A/A, the melanocyte population positive to the dopa reaction as well as the melanoblast-melanocyte population positive to the combined dopa-premelanin reaction increased dramatically until the 3rd day, then gradually decreased. In contrast, the melanocyte population of C3H/He did not increase after wounding, despite that the melanoblast-melanocyte population increased. Pigment-producing melanocytes in mitosis were frequently found in C57BL/10J and C57BL/10J-A/A, but not in C3H/He. The F1, F2, and backcross matings were performed to get some information about the genetic basis of the difference between C57BL/10J and C3H/He. In the F1 generation the offspring from reciprocal crosses exhibited intermediate values in both populations on the 3rd day after wounding. The F2 generation included the C3H/He type, F1 type, and C57BL/10J type in a ratio of 1:2:1 in both populations. Moreover, both reciprocal backcrosses gave 1:1 ratios of parent type to F1 type in both populations. These results indicate that the proliferative activity of mouse epidermal melanocytes during the healing of skin wounds are controlled by semidominant genes.

scholarly journals SERT and BDNF polymorphisms interplay on neuroticism in borderline personality disorder

2020 ◽  
Author(s):  
Valeria Salinas ◽  
Juana Villarroel ◽  
Hernán Silva ◽  
Luisa Herrera ◽  
Sonia Jerez ◽  
...  
Keyword(s):  
Borderline Personality Disorder ◽  
Personality Disorder ◽  
Personality Traits ◽  
Genetic Factors ◽  
Borderline Personality ◽  
Genetic Constitution ◽  
Val66met Polymorphism ◽  
Bdnf Val66met Polymorphism ◽  
S Allele ◽  
The Brain

Abstract Objective Genetic factors underlying different personality traits are not entirely understood, particularly how genes interact to modulate their effect. We studied 76 patients diagnosed with borderline personality disorder (BPD), characterized by extreme levels of personality traits, especially neuroticism (N), in which we genotyped two polymorphisms, the 5HTTLPR of the Serotonin transporter (SERT) gene, and the Val66Met of the Brain-derived neurotrophic factor (BDNF) gene.Results We found an association with SERT, where S-allele carriers had significantly higher levels of N than L-homozygous. Furthermore, we found that the protective effect of L-homozygosity is only evident on A-allele carriers of the BDNF Val66Met polymorphism. Genetic constitution in SERT and BDNF seems to be important in neuroticism, the most relevant personality trait on BPD.

scholarly journals SERT and BDNF polymorphisms interplay on neuroticism in borderline personality disorder

2019 ◽  
Author(s):  
Valeria Salinas ◽  
Juana Villarroel ◽  
Hernán Silva ◽  
Luisa Herrera ◽  
Sonia Jerez ◽  
...  
Keyword(s):  
Borderline Personality Disorder ◽  
Personality Disorder ◽  
Personality Traits ◽  
Genetic Factors ◽  
Borderline Personality ◽  
Genetic Constitution ◽  
Bdnf Gene ◽  
Bdnf Val66met Polymorphism ◽  
S Allele ◽  
The Brain

Abstract Objective: Genetic factors underlying different personality traits are not entirely understood, particularly how genes interact to modulate their effect. We studied 76 patients diagnosed with borderline personality disorder (BPD), characterized by extreme levels of personality traits, especially neuroticism (N), in which we genotyped two polymorphisms, the 5HTTLPR of the Serotonin transporter (SERT) gene, and the Val66Met of the Brain-derived neurotrophic factor (BDNF) gene. Results: We found an association with SERT, where S-allele carriers had significantly higher levels of N than L-homozygous. Furthermore, we found that the protective effect of L-homozygosity is only evident on A-allele carriers of the BDNF Val66Met polymorphism. Genetic constitution in SERT and BDNF seems to be important in neuroticism, the most relevant personality trait on BPD.

Association of pituitary adenoma with neuronal christoma: A TEM study

1994 ◽  
Vol 52 ◽  
pp. 232-233
Author(s):  
Eva Horvath ◽  
Kalman Kovacs ◽  
B. W. Scheithauer ◽  
R. V. Lloyd ◽  
H. S. Smyth
Keyword(s):  
Growth Hormone ◽  
Pituitary Adenoma ◽  
Pituitary Tumor ◽  
Nervous Tissue ◽  
Alternative Explanation ◽  
Growth Hormone Releasing Hormone ◽  
Cell Hyperplasia ◽  
Releasing Hormone ◽  
Secretory Neurons

The association of a pituitary adenoma with nervous tissue consisting of neuron-like cells and neuropil is a rare abnormality. In the majority of cases, the pituitary tumor is a chromophobic adenoma, accompanied by acromegaly. Histology reveals widely variable proportions of endocrine and nervous tissue in alternating or intermingled patterns. The lesion is perceived as a composite one consisting of two histogenetically distinct parts. It has been suggested that the neuronal component, morphologically similar to secretory neurons of the hypothalamus, may initiate adenoma formation by releasing stimulatory substances. Immunoreactivity for growth hormone releasing hormone (GRH) in the neuronal component of some cases supported this view, whereas other findings such as consistent lack of growth hormone (GH) cell hyperplasia in the lesions called for alternative explanation.Fifteen tumors consisting of a pituitary adenoma and a neuronal component have been collected over a 20 yr. period. Acromegaly was present in 11 patients, was equivocal in one, and absent in 3.

Genetic Factors in the Etiology of Duodenal Ulcer

1961 ◽  
Vol 40 (3) ◽  
pp. 371-378 ◽  
Author(s):  
David A. Price Evans
Keyword(s):  
Duodenal Ulcer ◽  
Genetic Factors
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