Jouni Uitto

Thomas Jefferson University | Jefferson · Department of Dermatology & Cutaneous Biology

Human papillomaviruses (HPVs), are DNA viruses, including ~450 types, classified into five genera (α-, β-, γ-, µ-, and 𝜈-HPV). The γ- and β-HPVs are present in low-copy numbers in healthy individuals, however, in patients with an inborn error of immunity, certain species of β-HPVs can cause epidermodysplasia verruciformis (EV), manifesting as recal...

Keloid disorder, a group of fibroproliferative skin disorders, is clinically comprised of keloids, hypertrophic scars, keloidalis nuchae, and acne keloidalis. The prototype of these disorders is keloids, which manifest as cutaneous lesions with excessive deposition of collagen following an initiating trauma of varying degrees. The principal cell ty...

Inborn errors of IFN-γ immunity can underlie tuberculosis (TB). We report three patients from two kindreds without EBV viremia or disease but with severe TB and inherited complete ITK deficiency, a condition associated with severe EBV disease that renders immunological studies challenging. They have CD4⁺ αβ T lymphocytopenia with a concomitant expa...

Background: Keloids are common and have significant negative effects on quality of life. There is a need for more effective treatment approaches for keloids. Aims: We investigated treatment outcomes of intralesional triamcinolone acetonide (IL TAC) compared with combination IL TAC and cryotherapy, including changes in pruritus, pain, and keloid...

Acquired ichthyosis (AI) is a relatively rare cutaneous entity characterized by transient, generalized scaling and pruritus in the absence of family history of ichthyosis or atopic disease. The hyperkeratosis in AI can range from the mild, white‐to‐brown scaling resembling that in ichthyosis vulgaris (IV) to the more prominent dark brown scaling ph...

Recalcitrant warts, caused by human papillomaviruses (HPVs), can be a cutaneous manifestation of inborn error of immunity. This study investigated the clinical manifestations, immunodeficiency, single-gene susceptibility, and HPV repertoire in a consanguineous family with severe sinopulmonary infections and recalcitrant warts. Clinical and immunolo...

Great advances have been made in the field of heritable skin disorders using next-generation sequencing (NGS) technologies (i.e., whole-genome sequencing, whole-exome sequencing, whole-transcriptome sequencing, and disease-targeted multi-gene panels). When NGS first became available, the cost and lack of access to these technologies were limiting f...

Plectin, encoded by PLEC, is a cytoskeletal linker and intermediate filament protein expressed in many cell types. Plectin consists of three main domains that determine its functionality: the N-terminal domain, the Rod domain, and the C-terminal domain. Molecular defects of PLEC correlating with the functional aspects lead to a group of rare herita...

Recessive dystrophic epidermolysis bullosa (RDEB) manifests with blistering and erosions of the skin and mucous membranes due to mutations in COL7A1. The repetitive wound healing processes lead to extensive cutaneous scarring. The scarring is driven by inflammatory processes, particularly the TGF‐β signaling pathways, resulting in excess synthesis...

Pseudoxanthoma elasticum (PXE), a heritable multisystem ectopic calcification disorder, is predominantly caused by inactivating mutations in ABCC6. The encoded protein, ABCC6, is a hepatic efflux transporter and a key regulator of extracellular inorganic pyrophosphate (PPi). Recent studies demonstrated that deficiency of plasma PPi, a potent endoge...

Pseudoxanthoma elasticum (PXE) and generalized arterial calcification of infancy (GACI) are clinically distinct genetic entities of ectopic calcification associated with differentially reduced circulating levels of inorganic pyrophosphate (PPi), a potent endogenous inhibitor of calcification. Variants in ENPP1, the gene mutated in GACI, have not be...

Ichthyosis follicularis (IF) manifests as generalized spiny follicular projections found in syndromic diseases secondary to SREBF1 and MBTPS2 mutations. We sought the genetic cause of IF in two distinct families from a cohort of 180 ichthyosis patients. In Family 1, the proband presented with IF, bilateral sensorineural hearing loss (SNHL) and punc...

ENPP1 encodes ENPP1, an ectonucleotidase catalyzing hydrolysis of ATP to AMP and inorganic pyrophosphate (PPi), an endogenous plasma protein physiologically preventing ectopic calcification of connective tissues. Mutations in ENPP1 have been reported in associated with a range of human genetic diseases. In this mutation update, we provide a compreh...

Epidermolysis bullosa (EB), a phenotypically and genetically heterogeneous disorder, has been linked to mutations in the genes encoding structural proteins that reinforce skin integrity via dermal-epidermal adhesion. Breakdowns in these adhesion mechanisms result in four different subtypes of EB classified on the basis of the level of tissue separa...

Severe viral infections of the skin can occur in patients with inborn errors of immunity (IEI). We report an all-in-one whole-transcriptome sequencing-based method by RNA-Seq on a single skin biopsy for concomitant identification of the cutaneous virome and underlying IEI. Skin biopsies were obtained from normal and lesional skin from patients with...

An 82‐year‐old female patient presented with a recent onset of painful skin lesions in unilateral distribution on the abdominal area following the lines of Blaschko; the initial diagnosis of Varicella‐zoster infection was made. However, because the individual lesions appeared as hyperkeratotic papules and were unresponsive to antiviral therapy, a s...

Recalcitrant warts (RW), caused by human papillomaviruses (HPVs), can be a cutaneous manifestation of inborn error of immunity. This study investigated the clinical manifestations, immunodeficiency, single-gene susceptibility, and HPV repertoire in a consanguineous family with severe sinopulmonary infections and RWs. Clinical and immunological eval...

DST encodes bullous pemphigoid antigen‐1 (BPAG1), a protein with eight tissue‐specific isoforms expressed in the skin, muscle, brain, and nerves. Accordingly, mutations in this gene are associated with epidermolysis bullosa simplex (EBS) and hereditary sensory and autonomic neuropathy type 6 (HSAN‐VI). The genotypic spectrum is attested to by 19 di...

Pseudoxanthoma elasticum (PXE) is a heritable ectopic calcification disorder with multi-organ clinical manifestations. The gene at default, ABCC6, encodes an efflux transporter, ABCC6, which is a new player regulating the homeostasis of inorganic pyrophosphate (PPi), a potent endogenous anti-calcification factor. Previous studies suggested that sys...

Pathologic soft tissue calcification can occur in both genetic and acquired clinical conditions causing significant morbidity and mortality. While the pathomechanisms of pathologic calcification are poorly understood, major progress has been made in recent years in defining the underlying genetic defects in Mendelian disorders of ectopic calcificat...

Background: Germline autosomal dominant and autosomal recessive mutations in PERP encoding p53 effector related to PMP-22 (PERP), a component of epidermal desmosomes, have been associated with a spectrum of keratodermas. Monoallelic nonsense mutations cause Olmsted syndrome with severe periorificial and palmoplantar keratoderma (PPK). Biallelic re...

There has been a significant increase in basal cell carcinoma (BCC) incidence, the most common cancer in humans, and the age of presentation with the first diagnosis of BCC has decreased in past decades. In this study, we investigated the possibility of genetic markers that can lead to earlier and closer observation of patients at high risk for dev...

Purpose Heritable ectopic mineralization disorders comprise a group of conditions with a broad range of clinical manifestations in nonskeletal connective tissues. We report the genetic findings from a large international cohort of 478 patients afflicted with ectopic mineralization. Methods Sequence variations were identified using a next-generatio...

Pseudoxanthoma elasticum (PXE; OMIM 264800) is a rare heritable multisystem disorder, characterized by ectopic mineralization affecting elastic fibers in the skin, eyes, and the cardiovascular system. Skin findings often lead to early diagnosis of PXE, but currently no specific treatment exists to counteract the progression of symptoms. PXE belongs...

Human papilloma virus (HPV) infections can cause common warts, which usually resolve spontaneously or become recalcitrant, resistant to multiple treatments. In rare cases, they transform into cutaneous giant horns resulting in the tree-man syndrome (TMS). Defective β-HPVs can cause flat warts in epidermodysplasia verruciformis (EV), a genetic disor...

Importance: Pyrin-associated autoinflammation with neutrophilic dermatosis (PAAND) is a monogenic autoinflammatory disorder with autosomal dominant inheritance and has been associated with monoallelic p.Ser242Arg and p.Glu244Lys variations in the MEFV gene. This dermatosis shares clinical features and pathogenesis with familial Mediterranean fever...

Pseudoxanthoma elasticum (PXE), a heritable multi-system ectopic mineralization disorder, is caused by inactivating mutations in the ABCC6 gene. The encoded protein ABCC6, a transmembrane transporter, has a specialized efflux function in hepatocytes by contributing to plasma levels of PPi, a potent inhibitor of mineralization in soft connective tis...

Background: Vascular calcification is an active process that increases cardiovascular disease (CVD) risk. There is still no consensus on an appropriate biomarker for vascular calcification. We reasoned that the biomarker for vascular calcification is the collection of all blood components that can be sensed and integrated into a calcification resp...

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare genodermatosis caused by mutations in the gene coding for type VII collagen (COL7A1). More than 800 different pathogenic mutations in COL7A1 have been described to date; however, the ancestral origins of many of these mutations have not been precisely identified. In this study, 32 RDEB pat...

Dermal Fibroblasts are the most accessible cells in the skin that have gained significant attention in cell therapy. Applying dermal fibroblasts' regenerative capacity can introduce new patterns to develop cell-based therapies to treat skin disorders. Dermal fibroblasts originate from mesenchymal cells and are located within the dermis. These cells...

We study a patient with the human papilloma virus (HPV)-2-driven “tree-man” phenotype and two relatives with unusually severe HPV4-driven warts. The giant horns form an HPV-2-driven multifocal benign epithelial tumor overexpressing viral oncogenes in the epidermis basal layer. The patients are unexpectedly homozygous for a private CD28 variant. The...

Objective: Well-defined germ-line mutations in the PTCH1 gene are associated with syndromic multiple basal cell carcinomas (BCCs). Here, we used whole exome sequencing (WES) to identify the role of patched-1 in patients with multiple, unusually large BCCs. Methods: A 72-year old patient presenting with numerous BCCs progressing to large ulcerati...

Over 1,000 heritable disorders have cutaneous manifestations, some of them being syndromic in association with extracutaneous manifestations, while others being limited to the skin. The genetic basis of many of these conditions has been deciphered, and mutation analysis by next-generation sequencing approaches, including whole-exome sequencing, who...

Objective:. Isolated hereditary hypotrichosis is caused by mutations in as many as 11 different genes. The conventional mutation detection strategy consists of sequencing of individual candidate genes separately, a time consuming and costly approach. In this study, we perform genome-wide single nucleotide polymorphism (SNP) array to identify candid...

Background Among the approximately 8000 Mendelian disorders, >1000 have cutaneous manifestations. In many of these conditions, the underlying mutated genes have been identified by DNA-based techniques which, however, can overlook certain types of mutations, such as exonic-synonymous and deep-intronic sequence variants. Whole-transcriptome sequencin...

Epidermolysis bullosa (EB) is a genotypically heterogeneous group of disorders characterized by cutaneous blistering and erosions with a tremendous spectrum of severity. One of the distinct forms of EB, Kindler EB (KEB), manifests with blistering and poikiloderma; this subtype of EB is caused by mutations in the FERMT1 gene encoding kindlin-1. In t...

Pseudoxanthoma elasticum (PXE), a prototype of heritable ectopic calcification disorders, affects the skin, eyes and the cardiovascular system due to inactivating mutations in the ABCC6 gene. There is no effective treatment for the systemic manifestations of PXE. In this study, the efficacy of INS-3001, an analogue of phytic acid, was tested for in...

The Mendelian Disorders of Cornification consist of a highly heterogeneous group of disorders, and the majority of non-syndromic cases belong to the family of autosomal recessive congenital ichthyosis (ARCI). Mutations in SDR9C7 have been associated with ACRI, and clinical manifestations include mild to moderately dry, scaly skin with or without hy...

Pseudoxanthoma elasticum (PXE), the prototype of heritable ectopic mineralization disorders, manifests with deposition of calcium hydroxyapatite crystals in the skin, eyes and arterial blood vessels. This autosomal recessive disorder, due to mutations in ABCC6, is usually diagnosed around the second decade of life. In the spectrum of heritable ecto...

Arrhythmogenic right ventricular cardiomyopathy (ARVC), with skin manifestations, has been associated with mutations in JUP encoding plakoglobin. Genotype–phenotype correlations regarding the penetrance of cardiac involvement, and age of onset have not been well established. We examined a cohort of 362 families with skin fragility to screen for gen...

In the past two decades, there has been great progress in identifying the molecular basis and pathomechanistic details in pseudoxanthoma elasticum (PXE), a heritable multisystem ectopic mineralization disorder. Although the identification of pathogenic variants in ABCC6 has been critical for understanding the disease process, genetic modifiers have...

ABCC6 encodes a transmembrane transporter playing a primary role in the efflux of ATP from hepatocytes to the bloodstream. ATP is then cleaved to AMP and inorganic pyrophosphate, a major inhibitor of ectopic calcification. Pathogenic variants of ABCC6 cause pseudoxanthoma elasticum, a multisystemic recessive ectopic calcification disease of variabl...

H syndrome is a complex multi-organ disorder with autosomal recessive inheritance. The skin manifestations include early onset hyperpigmentation and hypertrichosis, followed by skin induration often diagnosed as scleromyxedema and morphea. There is no effective treatment. Our objective was to study the efficacy of mycophenolate mofetil in a patient...

Keratitis-ichthyosis-deafness (KID) syndrome is caused by mutations in the GJB2 gene encoding connexin 26, a component of transmembrane hemichannels which form gap junction channels, critical for cell-cell communication. Here, we report two patients from two distinct families with KID syndrome with the same GJB2 mutation (p.Asp50Asn); in both cases...

Keloid disorder, a group of fibroproliferataive skin diseases, is characterized by unremitting accumulation of the extracellular matrix (ECM) of connective tissue, primarily collagen, to develop cutaneous tumors on the predilection sites of skin. There is a strong genetic predisposition for keloid formation, and individuals of African and Asian anc...

Objective:. Pseudoxanthoma elasticum (PXE) is a rare genetic disorder caused by loss-of-function mutations in the ABCC6 gene. While PXE is characterized by ectopic mineralization of connective tissues clinically affecting the skin, eyes, and cardiovascular system, kidney stones were reported in some individuals with PXE. The aim of this study is to...

Background Poorly healing wounds are one of the major complications in patients suffering from recessive dystrophic epidermolysis bullosa (RDEB). At present, there are no effective means to analyze changes in cellular and molecular networks occurring during RDEB wound progression to predict wound outcome and design betted wound management approache...

Pseudoxanthoma elasticum (PXE) is a multisystem disorder characterized by ectopic mineralization of connective tissues with primary manifestations in the skin, eyes, and cardiovascular system. The classic forms of PXE are caused by mutations in the ABCC6 gene encoding the ABCC6 protein expressed primarily in the liver. Cutis laxa (CL) manifests wit...

Vitiligo is a multifactorial skin disease with established role of genetics and autoimmunity in its pathogenesis. Vitamin D receptor (VDR) polymorphisms have been suggested to correlate with risk of vitiligo in some ethnic populations. On the other hand, cathelicidin, one of the innate immune system components, has a role in development of some chr...

Linked article: R. Mittwollen et al. J Eur Acad Dermatol Venereol 2020; 34: 2127–2134. https://doi.org/10.1111/jdv.16332.

The 2019 novel coronavirus' (COVID-19) pandemic became apparent in China during the International Congress on Epidermolysis Bullosa, (EB) in London, in January 2020. Many EB patients have medical problems that make them a vulnerable population of patients. Herein, we developed an international consensus to suggest best management of EB patients dur...

Mendelian disorders with cutaneous manifestations comprise a genotypically heterogeneous group of over 1,000 diseases, and in most of them mutant genes have been identified. Mutation detection approaches in these diseases have largely focused on DNA analysis by next-generation sequencing techniques, including gene-targeted sequencing panels as well...