BACKGROUND: Piebaldism is a rare autosomal dominant disorder characterized by congenital white forelock and depigmented patches, which is most commonly caused by deleterious variants in the KIT gene.
METHODS: Four KIT variants were identified in a piebaldism case series by whole-exome sequencing. Functional experiments, including in vitro minigene reporter assay and enzyme-linked immunosorbent assay, were carried out to elucidate the pathogenicity of the variants. The genotype-phenotype correlation was summarized through extensive literature reviewing.
RESULTS: All the four cases had severe piebaldism presented with typical white forelock and diffuse depigmentation on the ventral trunk and limbs. Four germline variants at the tyrosine kinase (TK) domains of the KIT gene were identified: two novel variants c.1990+1G>A (p.Pro627_Gly664delinsArg) and c.2716T>C (p.Cys906Arg), and two known variants c.1879+1G>A (p.Gly592_Pro627delinsAla) and c.1747G>A (p.Glu583Lys). Both splicing variants caused exon skipping and inframe deletions in the TK1 domain. The missense variants resided at the TK1 and TK2 domains respectively impairing PI3K/AKT and MAPK/ERK signaling pathways, the downstream of KIT. All severe cases were associated with variants in the TK domains, eliciting a major dominant-negative mechanism of the disease.
CONCLUSIONS: Our data expand the mutation spectrum of KIT, emphasized by a dominant-negative effect of variants in the critical TK domains in severe cases. We also share the experience of prenatal diagnosis and informed reproductive choices for the affected families.

Traits such as shape, size, and color often influence the economic and sentimental value of a horse. Around the world, horses are bred and prized for the colors and markings that make their unique coat patterns stand out from the crowd. The underlying genetic mechanisms determining the color of a horse\'s coat can vary greatly in their complexity. For example, only two genetic markers are used to determine a horse\'s base coat color, whereas over 50 genetic variations have been discovered to cause white patterning in horses. Some of these white-causing mutations are benign and beautiful, while others have a notable impact on horse health. Negative effects range from slightly more innocuous defects, like deafness, to more pernicious defects, such as the lethal developmental defect incurred when a horse inherits two copies of the Lethal White Overo allele. In this review, we explore, in detail, the etiology of white spotting and its overall effect on the domestic horse to Spot the Pattern of these beautiful (and sometimes dangerous) white mutations.

This review explores the psychosocial impact of vitiligo on patients, its consequences for their quality of life, and the need for holistic support. Vitiligo\'s psychosocial burden, driven by the need to conceal lesions and societal beauty ideals, leads to stress, sadness, and low self-esteem. Social stigma affects self-esteem, especially in cultural contexts, exacerbating the need for culturally sensitive support. Anxiety and depression are common due to visible differences and societal pressures. Vitiligo significantly reduces the quality of life, especially in younger patients, impacting daily activities, careers, and relationships. Disease severity worsens these effects, particularly in visible areas and among individuals with darker skin tones. Long-term disease activity may improve acceptance and quality of life. Psychological support and counseling are crucial, as many patients don\'t seek medical help. Education plays a key role, improving understanding and reducing anxiety. Raising awareness about the impact of vitiligo can challenge perceptions and contribute to enhancing patients\' well-being. In conclusion, this review highlights the interplay between psychosocial factors, quality of life, and the importance of addressing social stigma, providing psychological support, and advancing education and awareness for those with vitiligo.

Human skin pigmentation and melanin synthesis are incredibly variable, and are impacted by genetics, UV exposure, and some drugs. Patients\' physical appearance, psychological health, and social functioning are all impacted by a sizable number of skin conditions that cause pigmentary abnormalities. Hyperpigmentation, where pigment appears to overflow, and hypopigmentation, where pigment is reduced, are the two major classifications of skin pigmentation. Albinism, melasma, vitiligo, Addison\'s disease, and post-inflammatory hyperpigmentation, which can be brought on by eczema, acne vulgaris, and drug interactions, are the most common skin pigmentation disorders in clinical practice. Anti-inflammatory medications, antioxidants, and medications that inhibit tyrosinase, which prevents the production of melanin, are all possible treatments for pigmentation problems. Skin pigmentation can be treated orally and topically with medications, herbal remedies, and cosmetic products, but a doctor should always be consulted before beginning any new medicine or treatment plan. This review article explores the numerous types of pigmentation problems, their causes, and treatments, as well as the 25 plants, 4 marine species, and 17 topical and oral medications now on the market that have been clinically tested to treat skin diseases.

Vitamin C, also known as ascorbic acid, is used as a treatment modality in depigmentation of hyperpigmented spots on the skin and gingiva. This systematic review discusses the studies conducted to assess the effect of Vitamin C on melanin pigmentation. The primary objective was to evaluate the effect of Vitamin C on melanin pigmentation. The secondary objective was to analyze the effect of Vitamin C administration on melanin pigmentation. An electronic database search was conducted from the following databases: PubMed, EBSCOhost, ScienceOpen, EMBASE and Google Scholar. Randomized controlled trials, experimental studies, case-control studies and cohort studies published in peer-reviewed journals in English language were included. Case reports, case series, animal model studies, in vitro studies, studies where Vitamin C was used along with other agents and unpublished research were excluded. Out of 22,580 studies, only 7 studies satisfied the selection criteria. Data extraction sheet was prepared, and the studies were analyzed. Out of the 7 studies analyzed, 1 was a randomized controlled trial and 6 were experimental studies. Vitamin C has been used widely as a depigmenting agent in dermatology. However, there are limited studies conducted on the use of Vitamin C for gingival depigmentation.

BACKGROUND: Vitiligo is a relatively common acquired pigmentation disorder that can cause significant psychological stress and stigmatism.
OBJECTIVE: This article aims to familiarize physicians with the clinical manifestations, evaluation, diagnosis, and management of vitiligo.
METHODS: A Pubmed search was conducted in Clinical Queries using the key term \"vitiligo\". The search included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English language. The information retrieved from the above search was used in the compilation of the present article.
RESULTS: Approximately one quarter of patients with vitiligo have the onset before 10 years of age. Genetic, immunological, neurogenic and environmental factors may have a role to play in the pathogenesis. Vitiligo typically presents as acquired depigmented, well-demarcated macules/patches that appear milk- or chalk-white in color. Lesions tend to increase in number and enlarge centrifugally in size with time. Sites of predilection include the face, followed by the neck, lower limbs, trunk, and upper limbs. The clinical course is generally unpredictable. In children with fair skin, no active treatment is usually necessary other than the use of sunscreens and camouflage cosmetics. If treatment is preferred for cosmesis, topical corticosteroids, topical calcineurin inhibitors, and narrowband ultraviolet B phototherapy are the mainstays of treatment.
CONCLUSIONS: The therapeutic effect of all the treatment modalities varies considerably from individual to individual. As such, treatment must be individualized. In general, the best treatment response is seen in younger patients, recent disease onset, darker skin types, and head and neck lesions. Topical corticosteroids and calcineurin inhibitors are the treatment choice for those with localized disease. Topical calcineurin inhibitors are generally preferred for lesions on genitalia, intertriginous areas, face, and neck. Narrowband ultraviolet B phototherapy should be considered in patients who have widespread vitiligo or those with localized vitiligo associated with a significant impact on the quality of life who do not respond to treatment with topical corticosteroids and calcineurin inhibitors.

Autoimmune dermatoses targeting melanocytes have gained attention in human medicine due to their progressive nature and the social impact suffered by affected individuals. In veterinary medicine, vitiligo and the uveodermatological syndrome are the two autoimmune diseases that are known to affect skin melanocytes.In the first part of this article, we will review the signalment, clinical signs, histopathology and the treatment outcome of vitiligo in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. In a similar fashion, the information on the uveodermatological syndrome in dogs is reviewed and, where relevant, it is compared to the Vogt-Koyanagi-Harada (VKH) syndrome in humans.Canine, feline and equine vitiligo have many features that mirror their human counterparts. The most effective treatment and outcome of vitiligo in animals remain unclear. The canine uveodermatological syndrome resembles the incomplete VKH variant in humans; for affected individuals, an immediate diagnosis and aggressive treatment are crucial to prevent the development of blindness.

BACKGROUND: The discovery of signaling networks that drive oncogenic processes has led to the development of targeted anticancer agents. The burden of pigmentary adverse events from these drugs is unknown.
OBJECTIVE: To conduct a systematic review and meta-analysis of published clinical trials and determine the incidence and risk of development of targeted therapy-induced pigmentary changes.
METHODS: A comprehensive search was conducted to identify studies reporting targeted therapy-induced pigmentary changes. The incidence and relative risk were calculated. Case reports and series were reviewed to understand clinical characteristics.
RESULTS: A total of 8052 patients from 36 clinical trials were included. The calculated overall incidences of targeted cancer therapy-induced all-grade pigmentary changes in the skin and hair were 17.7% (95% confidence interval [CI], 11.9-25.4) and 21.5% (95% CI, 14.9-30.1), respectively. The relative risk of all-grade pigmentary changes of skin and hair were 93.7 (95% CI, 5.86-1497.164) and 20.1 (95% CI, 8.35-48.248). Across 53 case reports/series (N = 75 patients), epidermal growth factor receptor and breakpoint cluster region-abelson inhibitors were the most common offending agents.
CONCLUSIONS: Potential under-reporting and variability in oncologists reporting these events.
CONCLUSIONS: There is a significant risk of development of pigmentary changes during treatment with targeted anticancer therapies. Appropriate counseling and management are critical to minimize psychosocial impairment and deterioration in quality of life.

BACKGROUND: Oral pigmentation, especially in the gingiva poses esthetic problems. Laser therapy has been widely used for cosmetic therapy in dentistry. The aim of the present study was to systematically review the efficacy of surgical laser therapy (SLT) in the management of oral pigmented lesions (OPL).
METHODS: The addressed focused question was \"Is SLT effective in the management of OPL?\" Databases (MEDLINE via PubMed; EMBASE; Cochrane Central Register of Controlled Trials and Cochrane Oral Health Group Trials Register databases) were searched from 1970 up to and including February 2017.
RESULTS: Ten studies were included. The reported number of OPL ranged between 8 and 140. Oral pigmented sites included, gingiva, buccal and labial mucosa, alveolar mucosa and lips. Lasers used in the studies included Q-switched alexandrite, Neodymium-doped yttrium aluminium garnet, diode, Erbium: yttrium aluminium garnet and carbon dioxide laser. Laser wavelength, power output and number of irradiations were 635-10,600nm, 1-10W and 1 to 9 times, respectively. The follow up period ranged from 6 to 24months. All studies reported SLT to be effective in the treatment of OPL. In five studies, recurrence of OPL occurred which ranged from 21.4% to 45%.
CONCLUSIONS: Lasers are effective in the management of OPL including physiologic gingival pigmentation, smokers\' melanosis and pigmentation in Laugier-Hunziker syndrome. Different laser types (CO2, Er:YAG and Diode) showed comparable outcomes in the treatment of OPL.

Piebaldism is a rare autosomal dominant disorder characterized by an abnormal congenital skin pigmentation causing hypopigmented areas. It is due to an abnormal melanocytes development. It usually affects only the skin, but it may be associated with other anomalies or confused with other differential diagnoses. We report the case of a 5-year old boy with piebaldism having a family history of dermatologic phenotype without other alterations. We here highlight the pathogenesis, clinical manifestations, differential diagnosis as well as the management techniques and new therapeutic trials.