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Animal Genetics Jun 2020White-spotting coat colour phenotypes in cattle are either fixed characteristics of specific cattle breeds or occur sporadically owing to germline genetic variation of...
White-spotting coat colour phenotypes in cattle are either fixed characteristics of specific cattle breeds or occur sporadically owing to germline genetic variation of solid-coloured parents. A Brown Swiss cow showing a piebald pattern resembling colour-sidedness was referred for genetic evaluation. Both parents were normal solid-brown-coloured cattle. The cow was tested negative for the three known DNA variants in KIT, MITF and TWIST2 associated with different depigmentation phenotypes in Brown Swiss cattle. Whole-genome sequencing of the cow was performed and a heterozygous variant affecting the coding sequence of the bovine KIT gene was identified on chromosome 6. The variant is a 40 bp deletion in exon 9, NM_001166484.1:c.1390_1429del, and leads to a frameshift that is predicted to produce a novel 50 amino acid-long C-terminus replacing almost 50% of the wt KIT protein, including the functionally important intracellular tyrosine kinase domain (NP_001159956.1:p.(Asn464AlafsTer50)). Interestingly, among three available offspring, two solid-coloured daughters were genotyped as homozygous wt whereas a single son showing a slightly milder but still obvious depigmentation phenotype inherited a copy of the novel variant allele. The genetic findings provide strong evidence that the identified loss-of-function KIT variant most likely represents a de novo germline mutation that is causative owing to haploinsufficiency.
Topics: Animals; Cattle; DNA Mutational Analysis; Female; Frameshift Mutation; Germ-Line Mutation; Proto-Oncogene Proteins c-kit; Whole Genome Sequencing
PubMed: 32065668
DOI: 10.1111/age.12920 -
Communications Biology Feb 2020Two coat-color mutations, , which changes coat color from wild-type agouti to black, and , which induces irregular white spotting, are the characteristics of Japanese...
Two coat-color mutations, , which changes coat color from wild-type agouti to black, and , which induces irregular white spotting, are the characteristics of Japanese fancy mouse strain JF1/Ms. In our article, we reported that insertion of a rare type of endogenous retrovirus β4 has caused both coat color mutations. Although there are some reports on the roles of β4 in the mouse genome, further studies on β4 will uncover new features of endogenous retrovirus sequences.
Topics: Alleles; Animals; Biological Evolution; Endogenous Retroviruses; Hair Color; Mice; Mutagenesis, Insertional; Quantitative Trait, Heritable
PubMed: 32020010
DOI: 10.1038/s42003-020-0781-z -
G3 (Bethesda, Md.) Jan 2020The body coloration of animals is due to pigment cells derived from neural crest cells, which are multipotent and differentiate into diverse cell types. Medaka ()...
The body coloration of animals is due to pigment cells derived from neural crest cells, which are multipotent and differentiate into diverse cell types. Medaka () possesses four distinct types of pigment cells known as melanophores, xanthophores, iridophores, and leucophores. The () mutant of medaka is characterized by reduced numbers of melanophores and leucophores. We here identify () as the gene whose mutation gives rise to the phenotype. This identification was confirmed by generation of knockout medaka and the findings that these fish also manifest reduced numbers of melanophores and leucophores and fail to rescue the mutant phenotype. We also found that expression of , , , and genes is down-regulated in both and knockout medaka, implicating c-Kit signaling in regulation of the expression of these genes as well as the encoded transcription factors in pigment cell specification. Our results may provide insight into the pathogenesis of c-Kit-related pigmentation disorders such as piebaldism in humans, and our knockout medaka may prove useful as a tool for drug screening.
Topics: Animals; Fish Proteins; Melanophores; Microphthalmia-Associated Transcription Factor; Mutation; Oryzias; PAX7 Transcription Factor; SOXD Transcription Factors; Skin Pigmentation; Stem Cell Factor
PubMed: 31757930
DOI: 10.1534/g3.119.400561 -
International Journal of Dermatology Mar 2020
Topics: Adaptor Proteins, Signal Transducing; Adolescent; Amino Acid Substitution; DNA Mutational Analysis; Ethiopia; Female; Homozygote; Humans; Mutation, Missense; Piebaldism; Pigmentation Disorders; Siblings
PubMed: 31721180
DOI: 10.1111/ijd.14724 -
Annals of Dermatology Oct 2019We present 9-year-old fraternal twins from a family with piebaldism, having congenital depigmented macules and meeting the diagnostic criteria for neurofibromatosis type...
We present 9-year-old fraternal twins from a family with piebaldism, having congenital depigmented macules and meeting the diagnostic criteria for neurofibromatosis type 1 () due to the multiple café-au-lait macules (CALMs) and intertriginous freckling at the same time. It's still a debatable issue that CALMs and intertriginous freckling may be seen in the clinical spectrum of piebaldism or these patients should be regarded as coexistence of piebaldism and . However, based on recent literature and our patients' findings, we suggest that this rare phenotypic variant of piebaldism may not need the careful clinical follow-up and molecular testing for . Besides, it may be suitable that these individuals with piebaldism showing -like clinical phenotypes should be further tested for and gene mutations.
PubMed: 33911651
DOI: 10.5021/ad.2019.31.5.567 -
Pediatric Blood & Cancer Dec 2019
Topics: Antirheumatic Agents; Humans; Infant; Interleukin 1 Receptor Antagonist Protein; Lymphohistiocytosis, Hemophagocytic; Male; Piebaldism; Primary Immunodeficiency Diseases; Prognosis
PubMed: 31535456
DOI: 10.1002/pbc.27997 -
Biodiversity Data Journal 2019Piebaldism is a genetic pigmentation disorder, which is caused by absence of melanocytes in parts of the skin and/or hair follicles, with eyes and claws normally...
Piebaldism is a genetic pigmentation disorder, which is caused by absence of melanocytes in parts of the skin and/or hair follicles, with eyes and claws normally pigmented. The occurrence of piebaldism in natural populations is rare and the effects on fitness are still unknown. This article reports the first case of pigmentation disorders in the Fringe-lipped Bat (Spix, 1823) (Chiroptera: Phyllostomidae) caught in Barra do Triunfo, city of João Neiva, northeastern state of Espírito Santo, southeast Brazil.
PubMed: 31534412
DOI: 10.3897/BDJ.7.e38304 -
Diseases of Aquatic Organisms Aug 2019Atypical pigmentation, which is rarely observed in the wild, may influence social interactions between animals and can be detrimental for survival. Hypopigmentation,...
Atypical pigmentation, which is rarely observed in the wild, may influence social interactions between animals and can be detrimental for survival. Hypopigmentation, which is the lack of pigment in a part or on the entire body, is a type of atypical pigmentation pattern that can be either acquired (e.g. vitiligo) or congenital resulting from the inheritance of mutations in pigment-related genes (e.g. albinism, leucism and piebaldism). This study documents atypical pigmentation in a fin whale Balaenoptera physalus off the northwestern coast of the Iberian Peninsula (Atlantic Ocean). Photographic and video data collected between 2016 and 2017 on 30 individual fin whales were examined. One fully-grown fin whale exhibited hypopigmentation. Several white patches of different shapes and sizes were present across the body of the fin whale including on the head, body, dorsal fin, flippers, and flukes. The position, shape, and lack of inflammation of the white patches on the whale observed, along with its body length and condition, might indicate that the depigmentation pattern is due to vitiligo. To our knowledge, this is the first case of atypical pigmentation pattern in fin whales described with photographs and video records. As these observations are rare, especially in highly migratory, long-lived, marine mammal species, this study provides valuable information to better understand the occurrence of this phenomenon. Further studies are needed to determine the ecological and physiological implications of atypical colourations, which might have a significant influence on the animal's survival.
Topics: Animals; Atlantic Ocean; Fin Whale; Pigmentation; Whales
PubMed: 31392964
DOI: 10.3354/dao03385 -
JAAD Case Reports Jul 2019
PubMed: 31341943
DOI: 10.1016/j.jdcr.2019.01.021 -
Medicina (Kaunas, Lithuania) Jul 2019Congenital sensorineural hearing loss may occur in association with inborn pigmentary defects of the iris, hair, and skin. These conditions, named auditory-pigmentary...
Congenital sensorineural hearing loss may occur in association with inborn pigmentary defects of the iris, hair, and skin. These conditions, named auditory-pigmentary disorders (APDs), represent extremely heterogeneous hereditary diseases, including Waardenburg syndromes, oculocutaneous albinism, Tietz syndrome, and piebaldism. APDs are part of the neurocristopathies, a group of congenital multisystem disorders caused by an altered development of the neural crest cells, multipotent progenitors of a wide variety of different lineages, including those differentiating into peripheral nervous system glial cells and melanocytes. We report on clinical and genetic findings of two monozygotic twins from a large Albanian family who showed a complex phenotype featured by sensorineural congenital deafness, severe neuropsychiatric impairment, and inborn pigmentary defects of hair and skin. The genetic analyzes identified, in both probands, an unreported co-occurrence of a new heterozygous germline pathogenic variant (c.2484 + 5G > T splicing mutation) in the gene, consistent with the diagnosis of piebaldism, and a heterozygous deletion at chromosome 15q13.3, responsible for the neuropsychiatric impairment. This case represents the first worldwide report of dual locus inherited syndrome in piebald patients affected by a complex auditory-pigmentary multisystem phenotype. Here we also synthesize the clinical and genetic findings of all known neurocristopathies characterized by a hypopigmentary congenital disorder.
Topics: Female; Hearing Loss, Sensorineural; Humans; Male; Middle Aged; Piebaldism; Polymerase Chain Reaction; Twins; Young Adult
PubMed: 31284637
DOI: 10.3390/medicina55070345