The Hybridization Work of Mendel, 102 Years After Starting the Controversy Revista Científica, Vol
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Revista Científica ISSN: 0798-2259 [email protected] Universidad del Zulia Venezuela Román-Bravo, Rafael María; Garcidueñas-Piña, Rogelio; Ortiz-Rodríguez, Ruy; Atencio-León, Atilio Miguel; Yáñez-Cuéllar, Luis Fabián; Aranguren-Méndez, José Atilio The hybridization work of mendel, 102 years after starting the controversy Revista Científica, vol. XXIV, núm. 1, enero-febrero, 2014, pp. 38-46 Universidad del Zulia Maracaibo, Venezuela Available in: http://www.redalyc.org/articulo.oa?id=95930052008 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative ____________________________________________________Revista Científica, FCV-LUZ / Vol. XXIV, Nº 1, 38 - 46, 2014 THE HYBRIDIZATION WORK OF MENDEL, 102 YEARS AFTER STARTING THE CONTROVERSY El Trabajo de Hibridación de Mendel, 102 Años después del Inicio de la Controversia Rafael María Román-Bravo 1*, Rogelio Garcidueñas-Piña 2, Ruy Ortiz-Rodríguez 2, Atilio Miguel Atencio-León 2, Luis Fabián Yáñez-Cuéllar 1 and José Atilio Aranguren-Méndez 1 1Facultad de Ciencias Veterinarias, Universidad del Zulia, Maracaibo, Venezuela. 2Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México. 3Decanato de Ciencias Veterinarias, Universidad Centro Occidental “Lisandro Alvarado” Barquisimeto, estado Lara, Venezuela. *[email protected] ABSTRACT RESUMEN This research was carried out in order to verify by simulation El propósito de esta investigación fue verificar por simulación Mendel’s laws and seek for the clarification, from the author’s las leyes de Mendel y contribuir al esclarecimiento de la con- point of view, the Mendel-Fisher controversy. It was demons- troversia Fisher-Mendel. Para ello, se demuestra a partir de: trated from: the experimental procedure and the first two steps el procedimiento experimental y los dos primeros pasos de la of the Hardy-Weinberg law, that the null hypothesis in such ex- ley de Hardy-Weinberg que la hipótesis nula, en tales experi- periments is absolutely and undeniably true. Consequently, re- mentos es, sin lugar a dudas absolutamente cierta. En conse- peating hybridizing experiments as those showed by Mendel, it cuencia, al repetir experimentos de híbridos tal como los plan- makes sense to expect a highly coincidence between the ob- teó Mendel, lo más lógico es esperar una alta coincidencia en- served and the expected cell frequencies. By simulation, 30 tre las frecuencias observadas y las esperadas. Mediante si- random samples were generated with size equal to the number mulación, se generaron 30 muestras aleatorias con tamaño of observations reported by Mendel for his single trait trial, in igual al número de observaciones reportadas por Mendel para this case, seed shape; assuming complete dominance, with un sólo carácter, en este caso, la forma de la semilla, asu- genes A and a; likewise, it was simulated the results for the ex- miendo dominancia completa, con alelos A y a. Así mismo, se periment with two traits, segregating in separate chromoso- simularon los resultados del experimento con dos caracteres, mes, in this case seed shape, as before, and albumen color, segregando en cromosomas independientes, en este caso la with genes B and b, both loci with complete dominance. In the forma de la semilla y el color del albumen, este último con ale- case of a single trait, the data only showed evidence for rejec- los B y b; asumiendo dominancia completa en ambos loci. ting the null hypothesis (Ho) in 1/30 samples, with (P<0.05). In Para el caso de un carácter, los resultados sólo muestran evi- the case of the 30 samples of the two traits experiment, (Ho) dencia para rechazar la hipótesis nula (Ho) en 1/30 muestras, was rejected only on 3/30 times, when it was set a = 0.05. In con (P<0,05). En el caso del experimento con dos caracteres, both simulations there was a high correspondence between (Ho) fue rechazada en 3/30, oportunidades; cuando se esta- the observed and expected cell frequencies, which is simply bleció a=0,05. Se observó una alta correspondencia entre las due to the fact that (Ho) is true, and under these conditions, frecuencias observadas y las esperadas, lo cual es debido al that is what would to expect. It was concluded, that Mendel hecho de que la (Ho) es verdadera, y en esas condiciones es had no reason to manipulate his data in order to make them to lo que es de esperar. Se concluye que Mendel no tenía razón coincide with his beliefs. Therefore, in experiment with a single alguna, para manipular los resultados con el propósito de ha- trait, and in experiments with two traits assuming complete do- cerlos coincidir con sus creencias. Por lo tanto en experimen- minance, segregation ratios are 3:1; and 9:3:3:1, respectively. tos con uno y dos caracteres, y dominancia completa, las pro- Consequently, Mendel’s laws, under the conditions as were porciones de segregación son 3:1 y 9: 3: 3: 1, respectivamen- described are absolutely valid and universal. te. En consecuencia, las leyes de Mendel, en las condiciones como las describe son absolutamente válidas y universales. Key words: Mendel’s laws, controversy Fisher-Mendel. Palabras clave: Leyes de Mendel, controversia Fisher-Men- del. Recibido: 01 / 07 / 2013 . Aceptado: 21 / 11 / 2013. 38 _______________________________________________________________Revista Científica, FCV-LUZ / Vol. XXIV, Nº 1, 38 - 46, 2014 INTRODUCTION The attention of Fisher [6] was called because of all ex- periments, the results do not provide evidence to reject the In 1865, an Austrian monk, with knowledge of Biology, null hypothesis (Ho), Fisher did not think that the reason for Mathematics and Physics, presented a paper that was published such a coincidence, had to be sought in the nature of the ex- a year later [12], at the conference, he recounts the experiences periment and the experimental plan, this because of Correns’ collected over a period of approximately eight years, on plant hy- previous observation [4]. bridization [3]. That work, is a jewel of research methodology, ac- Pilgrim [18] is one of the researchers who has defended cording to the criteria of one of the re-discoverers of the work, the honesty of Mendel, according to him, the latter, did nothing who argues that he was tempted to leave his research, because else but to publish his results with impeccable fidelity, and ar- he was getting the same results and the same conclusions [4]. gued that it is a discredit to science have not recognized him The experiments were made in a sequential order, in order to during his lifetime furthermore, it is unfortunate to slander him. achieve goals, to confirm hypotheses, which lead to repeat ex- Later [19], he stated that the null hypothesis is correct, but with- periments, to establish new goals and in short, to build on a the- out explaining why, he did a good job on simulation, but felt in ory based on certainty, and someone stated that the success was the discussion of the coincidence of the results. This is the re- because Mendel included his mathematical skills in order to deci- searcher who has closed to the solution of the problem; he 2 pher the mystery of inheritance [16]. stated that if genetic studies were analyzed by using c tests, the Mendel, without much technical or theoretical resources high probability values are not unusual, if the results are consis- 2 distinguish from its predecessors, he simplified the problem by tent with the null hypothesis, he concluded that c test is not ap- reducing it to a minimum, being careful in detail with the experi- propriate to detect data counterfeit and that there is no reason to mental error. That work laid the foundations of genetics, but question Mendel’s honesty. Recently it was published a review was virtually ignored by his contemporaries, because accord- about the dispute, in which, it was concluded that the data was ing to Keines [10], it was only quoted in two theses, two not manipulated and even suggested that Fisher could be wrong authors whose books one of them is quoted in two other texts; [11]. In fact, it has been mentioned [16] that the reasons for likewise, it appeared in an encyclopedia, it was quoted three Fisher [6], to argue distortions are unfounded. times in the German journal Flora, and in the memories of the Later, Hartl and Fairbanks [9], analyzing the problem Viennese Academy of Science. However, for some, the scien- and agreed that there is no basis for alleging falsifying data in tific community was not interested, or simply did not under- Mendel’s work, they wanted that Fisher’s allegation of deliber- stand the work [14]. In 1900, three researchers, working inde- ate falsification, can be set side, because in-depth analysis, it pendently re-discovered the work, one of them Correns [4], was shown that cannot be supported by convincing evidence. which with its conclusions is perhaps the one that gives the Recently, an investigation led to the conclusion that there is first indication of the accuracy of Mendel’s results. sufficient evidence of the introduction of systematic uncon- At a conference at the University of Cambridge in 1911, scious of some bias, and they showed a model that fits Men- Sir Ronald Aylmer Fisher, a geneticist and a remarkable man, del’s data, without contradict Fisher’s results [21]. However, who laid the foundation of modern statistics stated: “it is inter- most researchers in the topic, are still looking at the wrong esting that all of Mendel’s original results fall within the limits of place.