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1.
Plant Mol Biol ; 114(3): 44, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630172

RESUMEN

Albino tea cultivars have high economic value because their young leaves contain enhanced free amino acids that improve the quality and properties of tea. Zhonghuang 1 (ZH1) and Zhonghuang 2 (ZH2) are two such cultivars widely planted in China; however, the environmental factors and molecular mechanisms regulating their yellow-leaf phenotype remain unclear. In this study, we demonstrated that both ZH1 and ZH2 are light- and temperature-sensitive. Under natural sunlight and low-temperature conditions, their young shoots were yellow with decreased chlorophyll and an abnormal chloroplast ultrastructure. Conversely, young shoots were green with increased chlorophyll and a normal chloroplast ultrastructure under shading and high-temperature conditions. RNA-seq analysis was performed for high light and low light conditions, and pairwise comparisons identified genes exhibiting different light responses between albino and green-leaf cultivars, including transcription factors, cytochrome P450 genes, and heat shock proteins. Weighted gene coexpression network analyses of RNA-seq data identified the modules related to chlorophyll differences between cultivars. Genes involved in chloroplast biogenesis and development, light signaling, and JA biosynthesis and signaling were typically downregulated in albino cultivars, accompanied by a decrease in JA-ILE content in ZH2 during the albino period. Furthermore, we identified the hub genes that may regulate the yellow-leaf phenotype of ZH1 and ZH2, including CsGDC1, CsALB4, CsGUN4, and a TPR gene (TEA010575.1), which were related to chloroplast biogenesis. This study provides new insights into the molecular mechanisms underlying leaf color formation in albino tea cultivars.


Asunto(s)
Albinismo , Perfilación de la Expresión Génica , Temperatura , Frío , Clorofila
2.
BMC Med ; 22(1): 40, 2024 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-38281904

RESUMEN

BACKGROUND: To date, almost no research on the psychosocial implications of albinism has been conducted in France and an exploration of albinism-related experiences could be beneficial, in order to better understand this condition. The aim of this study was to examine how French people with albinism and their parents live with and adapt to this condition in all the areas of their lives. METHODS: Semi-structured phone interviews were conducted with 9 parent-child dyads, each participating separately. Participants were recruited by convenience sampling, thanks to the combined efforts of a patient association (Genespoir) and professionals from the partner medical referral centers involved in the project. Dyads in which the individual with albinism had any comorbidity were excluded. The interviews were then transcribed and subjected to in-depth thematic analysis. Two codebooks were constructed in a mirrored process: one for people with albinism; the other for their parents. They were finally merged at the end of the coding step. RESULTS: Four main categories were identified: personal perceptions and social representations of albinism, difficulties and obstacles encountered by people with albinism, resources and facilitators, and the importance of parent-child functioning. The results indicated that experiences of stigmatization during childhood and adolescence are common and that people with albinism face challenges in adapting to certain obstacles related to their visual impairments (VI) (e.g., inability to drive a car; eye strain...). Parents emerged as one, if not as the main, source of support for people with albinism throughout their development. Although external support systems exist to assist them in various aspects of their lives, some of them primarily rely on their own personal resources to cope. CONCLUSIONS: This research highlights the importance of a systemic and transdisciplinary approach to make sure families receive the support that best meets their needs.


Asunto(s)
Albinismo , Pueblo Europeo , Apoyo Familiar , Padres , Adolescente , Adulto , Humanos , Albinismo/epidemiología , Albinismo/psicología , Pueblo Europeo/psicología , Francia , Padres/psicología , Investigación Cualitativa , Estigma Social , Apoyo Social
3.
Int J Equity Health ; 23(1): 1, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167082

RESUMEN

BACKGROUND: Persons with albinism face challenges to their wellbeing, safety, and security, ranging from vision impairment and skin cancer to stigma and discrimination. In some regions, they also face human rights atrocities including mutilation and murder. Research on human rights and albinism is a relatively new field that has gained momentum since the United Nations appointment of an Independent Expert on the enjoyment of human rights by persons with albinism. In this paper, we present the results of a mixed methods study undertaken to identify priorities for research, advocacy, and policy on albinism and human rights. METHODS: The first component was a synthesis of peer-reviewed and grey literatures at the nexus of albinism, spiritual/cultural beliefs and practices, and human rights. We then conducted a priority-setting survey, informed by Delphi methods, on extant knowledge-practice gaps and research, advocacy, and policy priorities. Inclusion criteria included demonstrated expertise in the field (e.g., peer-reviewed publications, funded research), membership on national or international associations, or advocacy (civil society organizations) of more than 2 years in albinism and human rights. Thereafter, we gathered leading researchers, policy-makers, and civil society stakeholders for a Roundtable to gain consensus on these priorities. RESULTS: Access to skin and vision care, and education were not deemed high priority for research, likely because the evidence supporting the need for these is well established. However, they were priorities for advocacy and policy: what is needed is mobilization of this evidence through advocacy and implementation of such services (policy). Other social determinants of health (rurality, poverty, and gender equality) are present as subtext in the findings, more so than priorities for research, advocacy, or policy, despite their preponderance in the lives of persons with albinism. Research was prioritized on stigma and discrimination; advocacy; and witchcraft, but with some differentiation between Global North and Global South priorities. Priorities for research, advocacy, and policy vary in keeping with the explanatory frameworks at play, including how harmful practices and witchcraft are viewed. CONCLUSIONS: The lived experience of albinism is profoundly shaped by the social determinants of health (SDOH). Threats to the security and well-being of persons with albinism should be viewed through a human rights lens that encompasses the explanatory frameworks at play.


Asunto(s)
Albinismo , Política de Salud , Humanos , Derechos Humanos , Organizaciones , Determinantes Sociales de la Salud
4.
J Med Genet ; 60(12): 1245-1249, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37460203

RESUMEN

Albinism is a clinically and genetically heterogeneous group of conditions characterised by visual abnormalities and variable degrees of hypopigmentation. Multiple studies have demonstrated the clinical utility of genetic investigations in individuals with suspected albinism. Despite this, the variation in the provision of genetic testing for albinism remains significant. One key issue is the lack of a standardised approach to the analysis of genomic data from affected individuals. For example, there is variation in how different clinical genetic laboratories approach genotypes that involve incompletely penetrant alleles, including the common, 'hypomorphic' TYR c.1205G>A (p.Arg402Gln) [rs1126809] variant. Here, we discuss the value of genetic testing as a frontline diagnostic tool in individuals with features of albinism and propose a practice pattern for the analysis of genomic data from affected families.


Asunto(s)
Albinismo Oculocutáneo , Albinismo , Humanos , Albinismo/genética , Albinismo/diagnóstico , Albinismo Oculocutáneo/diagnóstico , Albinismo Oculocutáneo/genética , Pruebas Genéticas , Genotipo , Alelos
5.
Int J Mol Sci ; 25(2)2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38279271

RESUMEN

Albinism is characterized by a variable degree of hypopigmentation affecting the skin and the hair, and causing ophthalmologic abnormalities. Its oculocutaneous, ocular and syndromic forms follow an autosomal or X-linked recessive mode of inheritance, and 22 disease-causing genes are implicated in their development. Our aim was to clarify the genetic background of a Hungarian albinism cohort. Using a 22-gene albinism panel, the genetic background of 11 of the 17 Hungarian patients was elucidated. In patients with unidentified genetic backgrounds (n = 6), whole exome sequencing was performed. Our investigations revealed a novel, previously unreported rare variant (N687S) of the two-pore channel two gene (TPCN2). The N687S variant of the encoded TPC2 protein is carried by a 15-year-old Hungarian male albinism patient and his clinically unaffected mother. Our segregational analysis and in vitro functional experiments suggest that the detected novel rare TPCN2 variant alone is not a disease-causing variant in albinism. Deep genetic analyses of the family revealed that the patient also carries a phenotype-modifying R305W variant of the OCA2 protein, and he is the only family member harboring this genotype. Our results raise the possibility that this digenic combination might contribute to the observed differences between the patient and the mother, and found the genetic background of the disease in his case.


Asunto(s)
Albinismo , Proteínas de Transporte de Membrana , Humanos , Masculino , Adolescente , Hungría , Mutación , Proteínas de Transporte de Membrana/metabolismo , Albinismo/genética , Antecedentes Genéticos
6.
Int J Mol Sci ; 25(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38396851

RESUMEN

Guppies are small tropical fish with brightly colored bodies and variable tail shapes. There are two phenotypes of domestic guppy eye color: red and black. The wild type is black-eyed. The main object of this study was to identify candidate genes for the red-eyed phenotype in domestic guppies. We hope to provide molecular genetic information for the development of new domestic guppy strains. Additionally, the results also contribute to basic research concerning guppies. In this study, 121 domestic guppies were used for genomic analysis (GWAS), and 44 genes were identified. Furthermore, 21 domestic guppies were used for transcriptomic analysis, and 874 differentially expressed genes (DEGs) were identified, including 357 upregulated and 517 downregulated genes. Through GO and KEGG enrichment, we identified some important terms or pathways mainly related to melanin biosynthesis and ion transport. qRT-PCR was also performed to verify the differential expression levels of four important candidate genes (TYR, OCA2, SLC45A2, and SLC24A5) between red-eyed and black-eyed guppies. Based on the results of genomic and transcriptomic analyses, we propose that OCA2 is the most important candidate gene for the red-eyed phenotype in guppies.


Asunto(s)
Albinismo Oculocutáneo , Albinismo , Poecilia , Animales , Poecilia/genética , Proteínas Portadoras/genética , Genómica , Perfilación de la Expresión Génica
7.
BMC Med Inform Decis Mak ; 23(1): 106, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37312174

RESUMEN

BACKGROUND: Reduced or absence of melanin poses physical, social, and psychological challenges to individuals with albinism. Mobile health (mHealth) applications have the potential to improve the accessibility of information and services while reducing time and costs. This study aimed to develop and evaluate a mHealth application for self-management of albinism. METHODS: This applied study was conducted in two stages (development and evaluation) in 2022. Initially, the functional requirements were determined, and the conceptual model of the application was then developed using Microsoft Visio 2021. In the second phase, the application was evaluated using the Mobile Application Usability Questionnaire (MAUQ) involving patients with albinism to reflect their views on the usability of the application. RESULTS: The key capabilities of the application included: reminders, alerts, educational content, useful links, storage and exchange of images of skin lesions, specialist finder, and notifications for albinism-relevant events. Twenty-one users with albinism participated in the usability testing of the application. The users were predominantly satisfied with the application (5.53 ± 1.10; Max: 7.00). CONCLUSIONS: The findings of this study suggest that the developed mobile application could assist individuals with albinism to effectively manage their condition by considering the users' requirements and services that the application should deliver.


Asunto(s)
Albinismo , Aplicaciones Móviles , Automanejo , Telemedicina , Humanos , Examen Físico
8.
J Fish Biol ; 103(2): 439-442, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37148473

RESUMEN

We report the first case of partial albinism in the Critically Endangered angelshark, Squatina squatina. The encounter with this specimen took place while SCUBA diving on the beach of Tufia, located on the east coast of the island of Gran Canaria on 2 April 2021. This is also the first confirmed finding of an albino elasmobranch specimen in the Canary Island archipelago.


Asunto(s)
Albinismo , Piebaldismo , Tiburones , Animales , España
9.
J Fish Biol ; 103(2): 453-456, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37222449

RESUMEN

Albinism is a genetic condition expressed as a lack of integumentary and retinal melanin. Although documented across many vertebrate species, albinism and other skin disorders are rarely observed in elasmobranchs (sharks and rays). The present study describes the first confirmed case of albinism in American cownose ray (Rhinoptera bonasus), and three other juveniles of the species with undetermined skin disorders observed in São Paulo, southeastern Brazil. Pigmentation disorders have already been observed in American cownose rays from the North Atlantic, including two cases of leucism and a possible albinism. Based on the results, it was discussed the possible consequences of albinism for the ray survival as well as the possible causes for the undetermined skin disorders.


Asunto(s)
Albinismo , Tiburones , Rajidae , Animales , Brasil , Piel , Albinismo/genética
10.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37834145

RESUMEN

Chlorophyll is an indispensable photoreceptor in plant photosynthesis. Its anabolic imbalance is detrimental to individual growth and development. As an essential epigenetic modification, DNA methylation can induce phenotypic variations, such as leaf color transformation, by regulating gene expression. Albino line XN1376B is a natural mutation of winter wheat cultivar XN1376; however, the regulatory mechanism of its albinism is still unclear. In this study, we found that low temperatures induced albinism in XN1376B. The number of chloroplasts decreased as the phenomenon of bleaching intensified and the fence tissue and sponge tissue slowly dissolved. We identified six distinct TaPOR (protochlorophyllide oxidoreductase) genes in the wheat genome, and TaPOR2D was deemed to be related to the phenomenon of albinism based on the expression in different color leaves (green leaves, white leaves and returned green leaves) and the analysis of promoters' cis-acting elements. TaPOR2D was localized to chloroplasts. TaPOR2D overexpression (TaPOR2D-OE) enhanced the chlorophyll significantly in Arabidopsis, especially at two weeks; the amount of chlorophyll was 6.46 mg/L higher than in WT. The methylation rate of the TaPOR2D promoter in low-temperature albino leaves is as high as 93%, whereas there was no methylation in green leaves. Correspondingly, three DNA methyltransferase genes (TaMET1, TaDRM and TaCMT) were up-regulated in white leaves. Our study clarified that the expression of TaPOR2D is associated with its promoter methylation at a low temperature; it affects the level of chlorophyll accumulation, which probably causes the abnormal development of plant chloroplasts in albino wheat XN1376B. The results provide a theoretical basis for in-depth analysis of the regulation of development of plant chloroplasts and color variation in wheat XN1376B leaves.


Asunto(s)
Albinismo , Arabidopsis , Clorofila/metabolismo , Triticum/metabolismo , Temperatura , Fotosíntesis/genética , Metilación de ADN , Arabidopsis/metabolismo , Albinismo/genética , Albinismo/metabolismo , Hojas de la Planta/metabolismo
11.
Klin Monbl Augenheilkd ; 240(4): 617-635, 2023 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-36827996

RESUMEN

Nystagmus describes an involuntary, periodic movement of one or both eyes. About 1/600 children and adolescents have nystagmus, most of them idiopathic infantile nystagmus (IIN), also called "congenital nystagmus", which can be caused by mutations in the FRMD7 gene. Other frequent forms of nystagmus are latent nystagmus, which is usually associated with infantile strabismus, and nystagmus associated with albinism. Sometimes difficult to distinguish in young infants is a sensory nystagmus, where a defect in the visual system reduces vision and causes nystagmus. Causes include retinal dystrophies, congenital stationary night blindness and structural ocular defects including optic nerve hypoplasia or dense bilateral congenital cataracts. Unilateral nystagmus can be the sign of an anterior visual pathway lesion. Seesaw nystagmus may be associated with suprasellar and mesodiencephalic lesions and - rarely - with retinal dystrophies.The ophthalmology plays a key role in identifying the form of nystagmus. Children with new onset nystagmus, with spasmus nutans, with vertical or unilateral nystagmus and those with seesaw nystagmus require neurologic evaluation including imaging of the brain.The treatment of nystagmus depends on the underlying cause. Even minor refractive errors should be corrected, contact lenses offer advantages over glasses.Gabapentin and memantine, possibly also carbonic anhydrase inhibitors, are effective in treating IIN, nystagmus in albinism and sensory nystagmus. Nevertheless, pharmacologic treatment of nystagmus is rarely used in children; the reasons are the limited effects on vision, the need for lifelong therapy, and potential side effects. Eye muscle surgery (Anderson procedure, Kestenbaum procedure) can correct a nystagmus-related anomalous head posture. The concept of "artifical divergence" of Cüppers may help to decrease nystagmus intensity in patients whose nystagmus dampens with convergence. The four-muscle-tenotomy, which involves disinsertion and reinsertion of the horizontal muscles at the original insertion of both eyes, has a proven but limited positive effect on visual acuity.


Asunto(s)
Albinismo , Nistagmo Congénito , Nistagmo Patológico , Lactante , Adolescente , Niño , Humanos , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/genética , Nistagmo Patológico/terapia , Nistagmo Congénito/diagnóstico , Nistagmo Congénito/genética , Movimientos Oculares , Músculos Oculomotores/cirugía , Proteínas del Citoesqueleto/genética , Proteínas de la Membrana/genética
12.
BMC Genomics ; 23(1): 310, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35439938

RESUMEN

BACKGROUND: Leaf colour mutations are universally expressed at the seedling stage and are ideal materials for exploring the chlorophyll biosynthesis pathway, carotenoid metabolism and the flavonoid biosynthesis pathway in plants. RESULTS: In this research, we analysed the different degrees of albinism in apple (Malus domestica) seedlings, including white-leaf mutants (WM), piebald leaf mutants (PM), light-green leaf mutants (LM) and normal leaves (NL) using bisulfite sequencing (BS-seq) and RNA sequencing (RNA-seq). There were 61,755, 79,824, and 74,899 differentially methylated regions (DMRs) and 7566, 3660, and 3546 differentially expressed genes (DEGs) identified in the WM/NL, PM/NL and LM/NL comparisons, respectively. CONCLUSION: The analysis of the methylome and transcriptome showed that 9 DMR-associated DEGs were involved in the carotenoid metabolism and flavonoid biosynthesis pathway. The expression of different transcription factors (TFs) may also influence the chlorophyll biosynthesis pathway, carotenoid metabolism and the flavonoid biosynthesis pathway in apple leaf mutants. This study provides a new method for understanding the differences in the formation of apple seedlings with different degrees of albinism.


Asunto(s)
Albinismo , Malus , Albinismo/genética , Albinismo/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Epigenoma , Flavonoides/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Malus/genética , Malus/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Plantones/genética , Plantones/metabolismo , Transcriptoma
13.
Am J Hum Genet ; 104(6): 1127-1138, 2019 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-31155284

RESUMEN

Optimal lysosome function requires maintenance of an acidic pH maintained by proton pumps in combination with a counterion transporter such as the Cl-/H+ exchanger, CLCN7 (ClC-7), encoded by CLCN7. The role of ClC-7 in maintaining lysosomal pH has been controversial. In this paper, we performed clinical and genetic evaluations of two children of different ethnicities. Both children had delayed myelination and development, organomegaly, and hypopigmentation, but neither had osteopetrosis. Whole-exome and -genome sequencing revealed a de novo c.2144A>G variant in CLCN7 in both affected children. This p.Tyr715Cys variant, located in the C-terminal domain of ClC-7, resulted in increased outward currents when it was heterologously expressed in Xenopus oocytes. Fibroblasts from probands displayed a lysosomal pH approximately 0.2 units lower than that of control cells, and treatment with chloroquine normalized the pH. Primary fibroblasts from both probands also exhibited markedly enlarged intracellular vacuoles; this finding was recapitulated by the overexpression of human p.Tyr715Cys CLCN7 in control fibroblasts, reflecting the dominant, gain-of-function nature of the variant. A mouse harboring the knock-in Clcn7 variant exhibited hypopigmentation, hepatomegaly resulting from abnormal storage, and enlarged vacuoles in cultured fibroblasts. Our results show that p.Tyr715Cys is a gain-of-function CLCN7 variant associated with developmental delay, organomegaly, and hypopigmentation resulting from lysosomal hyperacidity, abnormal storage, and enlarged intracellular vacuoles. Our data supports the hypothesis that the ClC-7 antiporter plays a critical role in maintaining lysosomal pH.


Asunto(s)
Ácidos/química , Albinismo/etiología , Canales de Cloruro/genética , Fibroblastos/patología , Variación Genética , Enfermedades por Almacenamiento Lisosomal/etiología , Lisosomas/metabolismo , Albinismo/metabolismo , Albinismo/patología , Animales , Canales de Cloruro/fisiología , Femenino , Fibroblastos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Lactante , Enfermedades por Almacenamiento Lisosomal/metabolismo , Enfermedades por Almacenamiento Lisosomal/patología , Masculino , Ratones , Oocitos/metabolismo , Xenopus laevis
14.
Genes Cells ; 26(1): 31-39, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33147376

RESUMEN

The periodic albino mutant of Xenopus laevis is a recessive mutant, in which reduced amounts of melanin appear in the retinal pigment epithelium (RPE) and in melanophores at the late embryonic stage, after which both RPE and melanophores gradually depigment. Three types of pigment cells (melanophores, iridophores and xanthophores) have been reported to be affected in this albino. However, the causative gene of the periodic albinism remains unknown. Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder that affects humans and mice, which is caused by defective biogenesis of lysosome-related organelles (LROs). Two subgenomes (L and S) are present in the allotetraploid frog X. laevis. Comparison of genes between the chromosomes 1L and 1S revealed that the HPS type 4 (hps4) gene was present only in chromosome 1L. In the albino mutant, a 1.9 kb genomic deletion in the hps4.L gene including exons 7 and 8 caused a premature stop codon to create a truncated Hps4 protein. Injection of wild-type hps4.L mRNA into mutant embryos rescued the albino phenotype. These findings indicate that hps4 is a causative gene for the periodic albinism in X. laevis. The phenotype of this mutant should be reassessed from the perspective of LRO biogenesis.


Asunto(s)
Albinismo/genética , Eliminación de Gen , Proteínas de Xenopus/genética , Albinismo/metabolismo , Animales , Exones , Poliploidía , Xenopus laevis
15.
Ophthalmology ; 129(6): 708-718, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35157951

RESUMEN

PURPOSE: To characterize the genotypic and phenotypic spectrum of foveal hypoplasia (FH). DESIGN: Multicenter, observational study. PARTICIPANTS: A total of 907 patients with a confirmed molecular diagnosis of albinism, PAX6, SLC38A8, FRMD7, AHR, or achromatopsia from 12 centers in 9 countries (n = 523) or extracted from publicly available datasets from previously reported literature (n = 384). METHODS: Individuals with a confirmed molecular diagnosis and availability of foveal OCT scans were identified from 12 centers or from the literature between January 2011 and March 2021. A genetic diagnosis was confirmed by sequence analysis. Grading of FH was derived from OCT scans. MAIN OUTCOME MEASURES: Grade of FH, presence or absence of photoreceptor specialization (PRS+ vs. PRS-), molecular diagnosis, and visual acuity (VA). RESULTS: The most common genetic etiology for typical FH in our cohort was albinism (67.5%), followed by PAX6 (21.8%), SLC38A8 (6.8%), and FRMD7 (3.5%) variants. AHR variants were rare (0.4%). Atypical FH was seen in 67.4% of achromatopsia cases. Atypical FH in achromatopsia had significantly worse VA than typical FH (P < 0.0001). There was a significant difference in the spectrum of FH grades based on the molecular diagnosis (chi-square = 60.4, P < 0.0001). All SLC38A8 cases were PRS- (P = 0.003), whereas all FRMD7 cases were PRS+ (P < 0.0001). Analysis of albinism subtypes revealed a significant difference in the grade of FH (chi-square = 31.4, P < 0.0001) and VA (P = 0.0003) between oculocutaneous albinism (OCA) compared with ocular albinism (OA) and Hermansky-Pudlak syndrome (HPS). Ocular albinism and HPS demonstrated higher grades of FH and worse VA than OCA. There was a significant difference (P < 0.0001) in VA between FRMD7 variants compared with other diagnoses associated with FH. CONCLUSIONS: We characterized the phenotypic and genotypic spectrum of FH. Atypical FH is associated with a worse prognosis than all other forms of FH. In typical FH, our data suggest that arrested retinal development occurs earlier in SLC38A8, OA, HPS, and AHR variants and later in FRMD7 variants. The defined time period of foveal developmental arrest for OCA and PAX6 variants seems to demonstrate more variability. Our findings provide mechanistic insight into disorders associated with FH and have significant prognostic and diagnostic value.


Asunto(s)
Albinismo Ocular , Albinismo Oculocutáneo , Albinismo , Defectos de la Visión Cromática , Albinismo Ocular/diagnóstico , Albinismo Ocular/genética , Albinismo Oculocutáneo/diagnóstico , Albinismo Oculocutáneo/genética , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/genética , Proteínas del Citoesqueleto , Fóvea Central/anomalías , Humanos , Proteínas de la Membrana , Trastornos de la Visión/diagnóstico
16.
Respir Res ; 23(1): 112, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35509004

RESUMEN

BACKGROUND: HPS-1 is a genetic type of Hermansky-Pudlak syndrome (HPS) with highly penetrant pulmonary fibrosis (HPSPF), a restrictive lung disease that is similar to idiopathic pulmonary fibrosis (IPF). Hps1ep/ep (pale ear) is a naturally occurring HPS-1 mouse model that exhibits high sensitivity to bleomycin-induced pulmonary fibrosis (PF). Traditional methods of administering bleomycin as an intratracheal (IT) route to induce PF in this model often lead to severe acute lung injury and high mortality rates, complicating studies focusing on pathobiological mechanisms or exploration of therapeutic options for HPSPF. METHODS: To develop a murine model of HPSPF that closely mimics the progression of human pulmonary fibrosis, we investigated the pulmonary effects of systemic delivery of bleomycin in Hps1ep/ep mice using a subcutaneous minipump and compared results to oropharyngeal delivery of bleomycin. RESULTS: Our study revealed that systemic delivery of bleomycin induced limited, acute inflammation that resolved. The distinct inflammatory phase preceded a slow, gradually progressive fibrogenesis that was shown to be both time-dependent and dose-dependent. The fibrosis phase exhibited characteristics that better resembles human disease with focal regions of fibrosis that were predominantly found in peribronchovascular areas and in subpleural regions; central lung areas contained relatively less fibrosis. CONCLUSION: This model provides a preclinical tool that will allow researchers to study the mechanism of pulmonary fibrosis in HPS and provide a platform for the development of therapeutics to treat HPSPF. This method can be applied on studies of IPF or other monogenic disorders that lead to pulmonary fibrosis.


Asunto(s)
Síndrome de Hermanski-Pudlak , Fibrosis Pulmonar Idiopática , Albinismo , Animales , Bleomicina/toxicidad , Modelos Animales de Enfermedad , Fibrosis , Trastornos Hemorrágicos , Síndrome de Hermanski-Pudlak/inducido químicamente , Síndrome de Hermanski-Pudlak/genética , Fibrosis Pulmonar Idiopática/patología , Pulmón , Ratones
17.
Respir Res ; 23(1): 167, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739508

RESUMEN

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by improper biogenesis of lysosome-related organelles (LROs). Lung fibrosis is the leading cause of death among adults with HPS-1 and HPS-4 genetic types, which are associated with defects in the biogenesis of lysosome-related organelles complex-3 (BLOC-3), a guanine exchange factor (GEF) for a small GTPase, Rab32. LROs are not ubiquitously present in all cell types, and specific cells utilize LROs to accomplish dedicated functions. Fibroblasts are not known to contain LROs, and the function of BLOC-3 in fibroblasts is unclear. Here, we report that lung fibroblasts isolated from patients with HPS-1 have increased migration capacity. Silencing HPS-1 in normal lung fibroblasts similarly leads to increased migration. We also show that the increased migration is driven by elevated levels of Myosin IIB. Silencing HPS1 or RAB32 in normal lung fibroblasts leads to increased MYOSIN IIB levels. MYOSIN IIB is downstream of p38-MAPK, which is a known target of angiotensin receptor signaling. Treatment with losartan, an angiotensin receptor inhibitor, decreases MYOSIN IIB levels and impedes HPS lung fibroblast migration in vitro. Furthermore, pharmacologic inhibition of angiotensin receptor with losartan seemed to decrease migration of HPS lung fibroblasts in vivo in a zebrafish xenotransplantation model. Taken together, we demonstrate that BLOC-3 plays an important role in MYOSIN IIB regulation within lung fibroblasts and contributes to fibroblast migration.


Asunto(s)
Síndrome de Hermanski-Pudlak , Albinismo , Animales , Movimiento Celular , Fibroblastos/metabolismo , Trastornos Hemorrágicos , Síndrome de Hermanski-Pudlak/genética , Humanos , Losartán/metabolismo , Pulmón/metabolismo , Miosina Tipo IIB no Muscular/metabolismo , Receptores de Angiotensina , Pez Cebra
18.
Platelets ; 33(1): 168-170, 2022 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33426985

RESUMEN

B-cell lymphoproliferative diseases may be associated with acquired hemostasis disorders, such as acquired hemophilia A (AHA) caused by autoantibodies that neutralize factor VIII activity, and δ-storage pool deficiency, an abnormality of platelet function due to defective dense granules and impaired secretion. We describe the case of a 67-year-old man in whom these two acquired bleeding disorders were concomitantly present as the first clinical manifestation of an indolent non-Hodgkin lymphoma. Immunosuppressive therapy with prednisone was initially started to eradicate anti-FVIII antibodies, subsequently boosted with cyclophosphamide and rituximab, these medications being also chosen to treat the associated indolent lymphoma. Bleeding symptoms were first tackled with limited benefit by using rFVIIa and then rescued using recombinant porcine FVIII. After a 6 month's follow-up lymphoma and AHA were in remission and platelet function was improved. This case underlines the need of multiple and complex diagnostic and therapeutic approaches to rare acquired bleeding disorders associated with lymphoproliferative diseases.


Asunto(s)
Albinismo/complicaciones , Hemofilia A/etiología , Trastornos Hemorrágicos/complicaciones , Síndrome de Hermanski-Pudlak/complicaciones , Linfoma no Hodgkin/complicaciones , Anciano , Hemofilia A/fisiopatología , Humanos , Masculino
19.
Graefes Arch Clin Exp Ophthalmol ; 260(7): 2165-2173, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35072785

RESUMEN

PURPOSE: Albinism defines a group of genetic diseases which result from disordered melanin biosynthesis. Proliferative diabetic retinopathy (PDR) results from poorly controlled type 1 or 2 diabetes mellitus (DM) and can lead to blindness due to progressive neovascularisation. However, the treatment of PDR in patients with ocular/oculocutaneous albinism may be more challenging. In this study, we compared a group of patients with albinism and PDR, to a group with albinism and diabetes mellitus but no PDR, to examine the long-term implications. METHODS: Retrospective observational study included all patients with ocular albinism (OA) or oculocutaneous albinism (OCA) and DM who presented at a single specialist centre. Participants were allocated into either group 1 (eyes with PDR) or group 2 (all eyes without PDR). Statistical analysis was performed using SPSS V26.0. Between-group differences were investigated. RESULTS: Outcome data was available for 5 eyes from 3 participants in group 1 and 26 eyes from 13 participants in group 2. Despite interventions, a large and significant difference in vision at follow-up was observed between group 1 and group 2 (mean change in visual acuity: 1.11 (± 1.00) versus - 0.15 (± 0.46), respectively; p = < 0.0001). CONCLUSION: PDR is associated with poor long-term prognosis despite interventions for patients with albinism. Those without PDR appear to maintain stable vision. Alternative treatments for PDR and its complications may be required in this population. Measures to prevent the development of diabetic eye disease and progression towards PDR should be employed at an early stage.


Asunto(s)
Albinismo Oculocutáneo , Albinismo , Diabetes Mellitus , Retinopatía Diabética , Hiperopía , Albinismo Oculocutáneo/complicaciones , Albinismo Oculocutáneo/diagnóstico , Albinismo Oculocutáneo/genética , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Humanos , Neovascularización Patológica , Agudeza Visual
20.
Am J Primatol ; 84(6): e23305, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34270104

RESUMEN

Albinism-the congenital absence of pigmentation-is a very rare phenomenon in animals due to the significant costs to fitness of this condition. Both humans and non-human individuals with albinism face a number of challenges, such as reduced vision, increased exposure to ultraviolet radiation, or compromised crypticity resulting in an elevated vulnerability to predation. However, while observations of social interactions involving individuals with albinism have been observed in wild non-primate animals, such interactions have not been described in detail in non-human primates (hereafter, primates). Here, we report, to our knowledge, the first sighting of an infant with albinism in wild chimpanzees (Pan troglodytes schweinfurthii), including social interactions between the infant, its mother, and group members. We also describe the subsequent killing of the infant by conspecifics as well as their behavior towards the corpse following the infanticide. Finally, we discuss our observations in relation to our understanding of chimpanzee behavior or attitudes towards individuals with very conspicuous appearances.


Asunto(s)
Albinismo , Pan troglodytes , Interacción Social , Albinismo/veterinaria , Animales , Animales Recién Nacidos , Muerte
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