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Albinismo platinado en Liomys pictus (Mammalia: Heteromyidae)

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Abstract

Albinism is a genetic abnormality, it can manifest as hypopigmentation or absence of color in skin, fur and eyes. The survival rate of wild animals with albinism is usually low. This paper reports the record of a platinum albino female of painted spiny pocket mouse Liomys pictus from Guerrero state, Mexico.

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... El leucismo es un trastorno cromático no letal de origen genético (Beerman et al. 2004;Velandia-Perilla et al. 2013), que no es frecuente en mamíferos (Caro 2005;Abreu et al. 2013;Romero & Tirira 2017) y que resulta en la ausencia de melanina en animales que normalmente son pigmentados (Lawrence 1999;Álvarez de Villar et al. 2007), pero sin extenderse hasta el iris ocular (Acevedo & Aguayo 2008;Abreu et al. 2013;Lucati & López-Baucells 2016). Los individuos que presentan esta característica fenotípica probablemente sean seleccionados negativamente en sus poblaciones, debido a la dificultad de interaccionar con sus congéneres y a la alta detectabilidad ante sus depredadores, lo que trae como consecuencia una baja supervivencia y éxito reproductivo (Miller 2005;Martínez-Coronel et al. 2013;Romero-Briceño 2018). Sin embargo, el hallazgo de individuos adultos con esta condición, hace parecer que las consecuencias negativas mencionadas anteriormente no impiden su desarrollo (Camargo et al. 2014;Arriaga-Flores et al. 2016;Puig et al. 2017). ...
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Se reporta por primera vez un caso de leucismo en la especie Coendou prehensilis. El individuo fue hallado de forma fortuita en una zona de bosque perturbado en la región de Los Andes en Venezuela.
... El leucismo es una variación hipopigmentaria de la piel o del pelaje que puede estar presente en todo el cuerpo o formando islas de manchas en diferentes partes del cuerpo (Metallinos et al. 1994, Martínez-Coronel et al. 2013, Camargo et al. 2014, Samson et al. 2017. En estado silvestre son casos poco frecuentes que merecen ser reportados, por tal motivo en esta nota se da a conocer sobre un caso de leucismo parcial en Notosciurus granatensis en un ecosistema intervenido ubicado al suroeste de Ecuador, en la provincia de El Oro, cantón Pasaje, parroquia Loma Franco, sector La Loma (-3,382396, -79,783416, a 213 msnm). ...
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La presente nota da a conocer un caso de leucismo parcial en Notosciurus granatensis. El individuo fue avistado en la provincia de El Oro, cantón Pasaje, sector La Loma. El 7 de octubre de 2017, a las 12h44, se observó, entre un remanente de bosque tropical y un cultivo de cacao, presentaba hipopigmentación en la parte terminal de la cola. Si bien se desconoce la razón de su causa, se discuten posibles razones.
... The organisms that have partial albinism present a wide range of tones (Beermann et al., 2004). The leucism, is a hypopigmentary variation of skin or fur coat, which is presented throughout the body (Martínez-Coronel et al., 2013) or as isolated patches on different parts of the body "piebald" (Metallinos et al., 1994;Treitler et al., 2013;Camargo et al., 2014). Unlike albinism, leucism is characterized by not affecting the pigmentation of eyes, lips and blood vessels and it does no reduce the immune system's defense function (Robinson, 1973;Slominski et al., 2004). ...
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Leucism is a hypopigmentary decrease of skin or fur coat, which is presented throughout the body or as isolated whitish patches on different parts of the body "piebald"; without altering the pigmentation of the eyes, lips, blood vessels or harm to the immune system of the specimen. The specimen was identified in the Tababela plateau located in the inter-Andean valley of Pichincha, Ecuador, site of the new Quito airport. By using glue traps used to capture lizards, one individual of Reithrodontomys mexicanus soederstroemi showing leucism, was trapped in the wild. This individual presents an irregular distribution of melanin pigments throughout it’s body. This is the first case reported with leucism in nature for this endemic species of the inter-Andean xeric valleys near Quito.
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Mammalogy as a discipline was pursued in Mexico since the mid-17 th century. However, Mexican researchers were involved primarily in the mid-20 th century, when national scientific journals were established to emphasize research on mammals. In 2010, the Asociación Mexicana de Mastozoología, A. C., initiated the journal Therya. Therya has now completed its first decade of publication, and in this work, we analyze the articles and scientific notes published in Therya, focused on the studies of mammals in Mexican territory, including researchers and institutions, to describe the path that mammalogy has taken in recent years in Mexico. This synthesis therefore serves as a frame of reference for future mammalogy studies. We compiled all papers published in Therya during the period 2010-2019. We built a database gathering information from these publications such as authors, institutions and states of origin, study areas, capture methods, topics and taxa studied. We excluded from the analyses research outside of Mexico. We did a descriptive statistics analysis including mean, proportions, percentage and trends for each and all the sections. Therya has published 181 articles and 52 scientific notes on mammals distributed in Mexico. The majority of authors and institutions were from Mexico City. The states of southeastern Mexico were the most used as a study area, particularly Oaxaca and Chiapas. The orders Carnivora and Cetartiodactyla were the most studied, mainly using indirect methods. Trapping methods were most commonly used for small mammals. The least studied orders were Eulipotyphla, Cingulata, and Pilosa. The most studied topics are ecology, diversity, conservation and distribution. Therya has become one of the most important journals about mammal research in Mexico. Research in mammalo-gy, as reflected in the pages of Therya, is based in academic institutions with the metropolitan area of Mexico City, reflecting the institutional infrastructure and age, and possibly institutional budgetary factors. The southeast portion of the country is well studied due to the existence of regional institutions, as well as to the concentration of high biodiversity. The least studied regions of Mexico may be the result of a reduced number of research groups and social insecurity. Much research is focused on small mammals, making Sherman traps and mist nets the most used trapping methods; carnivores and cetartiodactyls are the most studied groups, using indirect study methods reducing study costs and effort. Ecology, diversity and distribution are the most studied topics, these studies allow the development of management plans. 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El sureste del país es más estudiado debido a la existencia de instituciones regionales además de la alta concentra-ción de biodiversidad. Las regiones menos estudiadas pueden relacionarse con la falta de grupos de investigación cercanos y la inseguridad. Muchas investigaciones se concentran en pequeños mamíferos, haciendo de las trampas Sherman y redes de niebla los métodos de trampeo más utilizados; carnívoros y cetartiodáctilos son los grupos más estudiados usando métodos de estudio indirecto que reducen los costos y es-fuerzo de estudio. La ecología, diversidad y distribución son los temas más estudiados, que pueden apoyar el desarrollo de planes de manejo.
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Albinism is a genetic condition that results in total hypopigmentation of the eyes, fur, skin, hair, scales, and feathers of an organism. Albinism might result in a selective disadvantage for affected animals. Cases of albinism have been previously recorded in Neotropical vertebrates, such as reptiles, mammals, birds, and fish. However, observing albinism in a wild population is still considered to be a rare event. This paper reports a unique case of complete albinism in a red-brocket deer (Mazama americana) living in the Brazilian Amazon rainforest. The individual was observed within the Biological Reserve of Pará State, one of the most deforested regions of the Brazilian Amazon. The survival of the albino red-brocket deer in the wild can be related to mechanisms of apostatic selection, which theorize the survival of individual prey animals whose mutations make them less likely to be attacked by predators. In other words, the more different a prey animal is from others, the less likely it will be targeted by predators. The high abundance prey animals within the Biological Reserve of Tapirapé seems to support this prediction. This report exemplifies the importance of monitoring the biodiversity and promoting the conservation of favorable habitats to support species multiplicity in highly fragmented regions, as in the Brazilian Amazon.
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Albinism is a genetic condition that results in total hypopigmentation of the eyes, fur, skin, hair, scales, and feathers of an organism. Albinism might result in a selective disadvantage for affected animals. Cases of albinism have been previously recorded in Neotropical vertebrates, such as reptiles, mammals, birds, and fish. However, observing albinism in a wild population is still considered to be a rare event. This paper reports a unique case of complete albinism in a red-brocket deer (Mazama americana) living in the Brazilian Amazon rainforest. The individual was observed within the Biological Reserve of Pará State, one of the most deforested regions of the Brazilian Amazon. The survival of the albino red-brocket deer in the wild can be related to mechanisms of apostatic selection, which theorize the survival of individual prey animals whose mutations make them less likely to be attacked by predators. In other words, the more different a prey animal is from others, the less likely it will be targeted by predators. The high abundance prey animals within the Biological Reserve of Tapirapé seems to support this prediction. This report exemplifies the importance of monitoring the biodiversity and promoting the conservation of favorable habitats to support species multiplicity in highly fragmented regions, as in the Brazilian Amazon.
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The piebald deletion complex is a set of overlapping chromosomal deficiencies surrounding the endothelin receptor B locus collected during the Oak Ridge specific-locus-test mutagenesis screen. These chromosomal deletions represent an important resource for genetic studies to dissect the functional content of a genomic region, and several developmental defects have been associated with mice homozygous for distinct piebald deletion alleles. We have used molecular markers to order the breakpoints for 20 deletion alleles that span a 15.7-18-cM region of distal mouse chromosome 14. Large deletions covering as much as 11 cM have been identified that will be useful for regionally directed mutagenesis screens to reveal recessive mutations that disrupt development. Deletions identified as having breakpoints positioned within previously described critical regions have been used in complementation studies to further define the functional intervals associated with the developmental defects. This has focused our efforts to isolate genes required for newborn respiration and survival, skeletal patterning and morphogenesis, and central nervous system development.
Article
To observe the morphology and physiology of the retina in rats 11 weeks after a constant (24-hour) but moderate (500-lux) illumination for 1 week. Levels of aspartate, gamma-aminobutyric acid (GABA), glutamate, glutamine, and taurine were measured by high-pressure liquid chromatography (HPLC) in the retina and vitreous humor of albino (Wistar) and pigmented (Long-Evans) rats. Semithin sections were used to determine retinal morphology. The TUNEL method was used to detect cells degenerating by apoptosis. Because the GABAergic system has been shown to be particularly sensitive to the loss of photoreceptors, an additional immunohistochemical study using anti-GABA, anti-glutamate decarboxylase (GAD)(67) and anti-GAD(65) antibodies was performed. No apparent morphologic changes were found in the retina of pigmented rats after constant illumination, whereas in albino rats disappearance of photoreceptors (except in the extreme retinal periphery) and cell bodies was observed. A significant number of TUNEL-positive nuclei also occurred in the remaining nuclear and ganglion cell layers. However, no change in the distribution of GABA, GAD(67), and GAD(65) immunoreactivities was found in either strain under constant illumination compared with control animals. Constant illumination affected the retinal levels of aspartate, glutamate, glutamine, glycine in both strains, whereas GABA contents did not change and taurine was decreased only in albino rats. A significant increase of vitreal glutamate levels was also found in both strains and of taurine levels only in albino rats. Phototoxicity can provoke durable retinal alterations beyond the period of lighting, suggesting progressive and probably continuous modifications of retinal physiology, even in pigmented animals in which the retina seems morphologically normal.
Article
Lysosomes are membrane-bound organelles that are found in all mammalian cells and contain hydrolases and lipases required for protein and membrane degradation. In many cells of the immune system, lysosomes also contain secretory proteins that can be released by regulated exocytosis in response to an external stimulus, providing different cell types with a wide range of effector functions. Melanosomes also use a lysosome-related organelle to secrete melanin for pigmentation. Links between albinism and immunity in patients have uncovered a number of key proteins required for lysosomal secretion and have revealed a versatile secretory mechanism that can be fine-tuned by distinct interactions in different cell types.
Article
The albino mouse was already known in ancient times and was apparently selectively bred in Egypt, China, and Japan. Thus, it is not surprising that the c or albino locus (now the Tyr locus) was among the first used to demonstrate Mendelian inheritance in mammals at the dawn of the past century. This locus is now known to encode tyrosinase, the rate-limiting enzyme in the production of melanin pigment, and the molecular basis of the albino (Tyr c ) mutation is known. Here we describe the congenic series of Tyr-locus alleles, from wild type to null (albino). We compare eye and skin pigmentation phenotypes and the genetic lesions that cause each. We suggest that this panel of congenic mutants contains rich, untapped resources for the study of many questions of basic cell biological interest.
Article
Albinism is due to a lack of pigmentation in hair, skin and eye, and has been shown to occur in several animal species. Mutations of the tyrosinase (TYR) gene account for albinism in domestic cats, rabbits, cattle, mice and rats. In this study, we demonstrate that a TYR mutation accounts for albinism in the ferret (Mustela putorius furo). The coding sequence of the five exons of TYR was determined in genomic DNA from wild-type pigmented 'sable' coloured and albino ferrets. It was not possible to amplify TYR exon 4 in albino ferrets originating from different breeds. The deletion of exon 4 in albino ferrets was confirmed by Southern blot hybridization of genomic DNA from albino and pigmented ferrets. This is the first report of a deletion of a TYR exon in a non-human mammal.
Article
There is an amazing amount of diversity in coloration patterns in nature. The ease of observing this diversity and the recent application of genetic and molecular techniques to model and nonmodel animals are allowing us to investigate the genetic basis and evolution of coloration in an ever-increasing variety of animals. It is now possible to ask questions about how many genes are responsible for any given pattern, what types of genetic changes have occurred to generate the diversity, and if the same underlying genetic changes occur repeatedly when coloration phenotypes arise through convergent evolution or parallel evolution.
Albinism in Thomomys talpoides from Colorado
  • G. K. LaVoie
  • H. P. Tietjen
  • M. W. Fall
Albinismo parcial em cutia Dasyprocta azarae (Lichtenstein,1823) (Rodentia, Dasyproctidae), no sul do Brasil
  • S. V. Oliveira
Human and mouse disorders of pigmentation
  • R. A. Spritz
  • P.-W. Chiang
  • N. Osio
  • A. Alkhateeb
An albino kangaroo rat
  • J. C. Von Bloeker
Melanin pigmentation in mammalian skin and its hormonal regulation
  • A. Slominski
  • D. J. Tobin
  • S. Shibahara
  • J. Wortsman
The selective advantage of crypsis in mice
  • S. N. Vignieri
  • J. G. Larson
  • H. E. Hoekstra
Evolution of coloration patterns
  • M. E. Protas
  • N. H. Pastel
Visual and other sensory abilities of mice and their influence on behavioral measures of cognitive function
  • A. A. Wong
  • R. E. Brown
  • L. M. Chalupa
  • R. W. Williams
From Darwin to DNA: The genetic basis of color adaptations
  • H. E. Hoekstra
  • J. Losos