Calpain Gene Research Articles

Systemic delivery of AAVrh74.tMCK.hCAPN3 rescues the phenotype in a mouse model for LGMD2A/R1

Limb girdle muscular dystrophy (LGMD) 2A/R1, caused by mutations in the CAPN3 gene and CAPN3 loss of function, is known to play a role in disease pathogenicity. In this study, AAVrh74.tMCK.CAPN3 was delivered systemically to two different age groups of CAPN3 knockout (KO) mice; each group included two treatment cohorts receiving low (1.17 × 1014 vg/kg) and high (2.35 × 1014 vg/kg) doses of the vector and untreated controls. Treatment efficacy was tested 20 weeks after gene delivery using functional (treadmill), physiological (in vivo muscle contractility assay), and histopathological outcomes. AAV.CAPN3 gene therapy resulted in significant, robust improvements in functional outcomes and muscle physiology at low and high doses in both age groups. Histological analyses of skeletal muscle showed remodeling of muscle, a switch to fatigue-resistant oxidative fibers in females, and fiber size increases in both sexes. Safety studies revealed no organ tissue abnormalities; specifically, there was no histopathological evidence of cardiotoxicity. These results show that CAPN3 gene replacement therapy improved the phenotype in the CAPN3 KO mouse model at both doses independent of age at the time of vector administration. The improvements were supported by an absence of cardiotoxicity, showing the efficacy and safety of the AAV.CAPN3 vector as a potential gene therapy for LGMDR1.

Research Article Haplotype-based case-control study of calpain (CAPN2) gene and hypertensive disorders of pregnancy

Research Article Haplotype-based case-control study of calpain (CAPN2) gene and hypertensive disorders of pregnancy

Calpainopathies: state of the art and therapeutic perspectives

Calpainopathies are inherited limb-girdle muscular dystrophies, most often following an autosomal recessive (AR) transmission. Autosomal dominant (AD) forms with less severe presentation are increasingly reported. Calpainopathies with autosomal recessive (AR) mutations of the calpain3 gene (CAPN3) are associated with limb girdle muscular dystrophy type R1 (LGMD-R1, OMIM 253600) also referred to as LGMD-2A according to the old nomenclature. LGMD-R1 is the commonest form of all LGMDs, with an estimated prevalence of 10 to 70 cases per million inhabitants, that is a cohort of between 670 and 4,200 patients in France theoritically. Patients present a symmetrical proximal axial myopathy manifesting itself between the first and second decade. The clinical course is variable. The level of Creatine- Kinase (CK) is usually high and there is no cardiac involvement. From a therapeutic perspective, the autosomal recessive form of calpainopathy is quite suitable to gene replacement strategies; the viability of recombinant AAV-mediated calpain 3 transfer has been demonstrated in animal models and clinical trials are expected in the coming years. Meanwhile, natural history studies are needed to prepare for future clinical trials.

Variants of CAPN3 cause limb-girdle muscular dystrophy type 2A in two Chinese families.

Limb-girdle muscular dystrophies (LGMDs) are a group of neuromuscular diseases that are characterized by progressive muscle weakness. LGMD type 2A (LGMD2A), caused by variants in the calpain-3 (CAPN3) gene, is the most prevalent type. The present study aimed to analyze pathogenic CAPN3 gene variants in two pedigrees affected by LGMD2A. Each family contains three patients who are siblings and sought genetic counseling. Genomic DNA was extracted from the peripheral blood samples collected from the probands and family members and whole-exome sequencing (WES) was used to detect the pathogenic genes in the probands. Suspected variants were subsequently validated by Sanger sequencing. In family 1, WES revealed that the proband carried the compound heterogeneous variants c.1194-9A>G and c.1437C>T (p.Ser479=) in CAPN3 (NM_000070.2). In family 2, WES identified that the proband carried the compound heterogeneous variants c.632+4A>G and c.1468C>T (p.Arg490Trp) in CAPN3 (NM_000070.2). In conclusion, the present study indicated that the compound heterogeneous variants of the CAPN3 gene were most likely responsible for LGMD2A in the two Chinese families.

Gender effects on pork quality and calpain-1 and calpastatin gene expression in male pig muscle

Studies that investigate the expression of genes related to the tenderness of meat from entire and immunocastrated male pigs have not yet been performed. The objective of this study was to investigate the association between gender (entire male and immunocastrated) and the meat quality of pigs, as well as to quantify the expression of calpain-1 and the calpastatin gene. Regarding carcass measurements and meat quality, boars presented lower values of muscle depth (P = 0.028), subcutaneous fat thickness (P = 0.046), L* value (P = 0.004) and cook loss (P = 0.008) than the immunocastrated pigs. The boars presented greater calpain-1 gene expression (P = 0.006) and lower calpastatin gene expression (P = 0.003) than immunocastrated pigs. This study shows that combined with other factors the gene expression can contribute to a tender meat from boars due to their higher calpain-1 expression and lower calpastatin expression than those of immunocastrated male pigs.

Biochemical and histological indicators of blood and m. longissimus dorsi of young bulls of Kazakh white-headed breed of different genotypes by the CAPN1 and GH genes

The use of molecular genetic markers for productivity is one of the modern approaches in breeding beef cattle. The article presents the results of the studies on the influence of genotypes by the calpain (CAPN1) and growth hormone (GH) genes on live weight, fatty acid composition of blood plasma, quantitative and qualitative indicators of meat of young cattle of Kazakh white-headed breed. It was established that animals of the homozygous geno-types СС–CAPN1 and VV-GH had a larger live weight and its average daily gain on the 240th and 365th days. Their superiority over the GG and LL genotypes was 13.8% (P<0.05) and 6.9%; 14.6% (P<0.05) and 6.9%, respectively. The carriers of the desirable alleles in the homozygous state had the sum of unsaturated fatty acids higher by 6.3% and 7.1%, respectively, than the young bulls, in which genotypes they were absent. The predominance of unsaturated fatty acids over saturated fatty acids also determined lower values of lipid me-tabolism direction index (0.92 and 1.00) in the animals with the desirable genotype. Muscle tissue of animals of the СС and VV genotypes was characterized by a higher level of protein, fat by 0.28–2.13 abs. per cent, energy value, and the quantity of muscle fibers with a smaller diameter per unit area compared to the GG and LL genotypes by on average 8.7% and 25.5% (P<0.01). Due to the greater number of interfiber fat inclusions, muscle tissue of the desirable genotypes received higher marbling scores. The obtained data testify to the prospects of replication of animals, which genotype has the desirable alleles for further improvement of traits of meat productivity of Kazakh white-headed breed.

The Calpain Gene is Correlated With Metal-on-Metal Hip Replacement Failures

BackgroundMetal-on-metal (MOM) total hip arthroplasty is associated with unacceptable failure rates secondary to metal ion reactions. Efforts to identify which patients will go on to failure have been limited; recently, there has been a suggestion for a potential genetic basis for the increased risk of revision in MOM hip replacements (MOMHRs). The purpose of this study is to determine whether certain immunologic genotypes are predictive of the need for revision in patients with MOM total hip implants. MethodsThis is a case-control study of all patients undergoing primary MOMHR between September 2002 and January 2012 with a minimum of 5-year follow-up. Our investigational “case” cohort was comprised of patients who underwent revision for MOMHR for a reason other than infection. A single-nucleotide polymorphism (SNP) array analysis was performed to identify a potential genetic basis for failure. ResultsThirty-two patients (15 case and 17 control) were included in our analysis. All patients in the revision group had a chief complain of pain; revision patients were more likely to have a posterior approach (P = .01) and larger head size (P = .04) than nonrevision patients. No patient or implant characteristics were independently associated with revision in a multivariate analysis. Patients with SNP kgp9316441 were identified as having an increased odds of revision for MOM failure (P < .001). ConclusionThis study identified an SNP, kgp9316441, encoding proteins associated with inflammation and macrophage activation. This SNP was associated with significantly increased odds of revision for MOMHR. Future studies are warranted to validate this gene target both in vitro and in vivo. Level of EvidenceIII.

Associations of CAST, CAPN1 and MSTN Genes Polymorphism with Slaughter Value and Beef Quality – A Review

Abstract The slaughter value of cattle and beef quality are influenced by many factors, which can generally be divided into antemortem (breed, sex, age, housing system, diet, pre-slaughter handling) and postmortem (post-slaughter processing, chilling temperature, packaging). Studies of many authors have shown that meat quality traits can be also influenced by the individual genetic background of an animal. Numerous studies have been conducted worldwide to determine the functions of various genes as well as polymorphisms with potential effects on fattening and slaughter value of cattle and on beef quality. This study reviews the most important research done on the associations of polymorphisms in the calpain, calpastatin and myostatin genes with carcass traits and beef quality. Knowledge about the genes and chromosome regions associated with desired meat quality characteristics may prove very helpful when selecting pairs for mating and estimating the breeding value of offspring, mainly because it is difficult to improve meat quality traits based on conventional selection methods due to their low heritability and polygenic regulation. Furthermore, meat quality evaluation is expensive and can only be carried out after slaughter.

Analysis of polymorphism of CAPN1 and GH genes in cattle of Kazakh White-Headed breed in association with the peculiarities of beef productivity

The intensive development of genetics at the molecular level has now opened up the possibility for breeders to identify and study genes that are directly or indirectly related to desirable economically useful traits. The purpose of the research was to identify desirable genotypes in the breeding of Kazakh White-Headed cattle based on the genes-markers of meat productivity of calpain (CAPN1) and somatotropin (GH) for use in breeding to increase meat productivity and beef quality. Experimental researches have been carried out on steers of the Kazakh White-Headed breed on the basis of the APC collective farm “Gigant” in the Blagodarnensky district in the Stavropol Territory. Analysis of growth and development indicators of calves has shown that the value of live weight and average daily gains was higher in calves carrying the C allele at calpain gene locus and V allele at somatotropin gene locus. Dominant alleles C and V in the homozygous state characterize the desired genotype of calves. During weaning the studied indicators were higher with a diff erence on average up to 13,0 % in young animals of homozygous genotypes (CC and VV). The largest number of muscle fi bers has been observed in steers with the desired CC and VV genotypes. They outperformed their herdmates with GG genotype by 36,82 pcs/мм² or 19,7 % in calpain gene group (CAPN1) by 55,7 pcs/мм² or 31,4 % in somatotropin gene group (GH), respectively. The diameter of muscle fibers in carcasses with the desired genotype was less by 4,23 microns or 11,9 %, and by 6,82 microns or 16,8 %. The meat of steers with homozygous CC and VV alleles according to the studied genes differed from the meat of animals with GG and LL genotypes by 12,6 % in calpain gene (CAPN1) and 15,1 % in somatotropin gene (GH). The connective tissue content was higher in animals with the undesirable type of G and L alleles than in animals of the desired genotype, by 2,13 and 3,34 abs. percent’s. The area of the eye of loin in animals of desired VV genotype of somatotropin cluster (GH) was higher than in animals of CC genotype of calpain cluster (CAPN1) by 4,84 cм² or 10,1 %.

The genetic quality improvement of native and local chickens to increase production and meat quality in order to build the Indonesian chicken industry

Native and local chickens have a great effect in the development of the local chicken industry in rural communities. Local chicken industry significantly contributes to the income value of national agricultural development as well as become an important foundation in building food self-sufficient. Indonesia has a wealth of genetic resources of native and local chicken with abundant genetic diversity, but has not been managed and utilized properly. In Indonesia, local chicken agribusiness is less developed due to lack of genetic improvement and has a direct impact with the very low contribution of meat and eggs. Indonesia has a variety of genetic sources for native and local chickens spread throughout the region. Native and local chickens contribute greatly to the rural economy but their production is still limited. Despite its low productivity, native chicken production is very important for rural communities. However, they face challenges how to increase the productivity of their population, which can benefit them financially and increase food security and reach market potential. This native chicken has the characteristics of slow growth and varied egg production. The development of the potential of native chicken and related issues of food security and food independence, local chicken is suitable for this. Information on the performance and productivity of local chickens is needed for local chicken development. Potential local chickens such as pelung chickens are known as singer chickens with a large body frame. Sentul chickens are another potential local chicken, known as meat-producing chickens with good egg production. Through breeding programs (selection and crossing), increasing the productivity of meat and eggs of native chicken can be done effectively. In addition, improving the quality of local chickens can be improved through conventional feeding management. The availability of selected local chicken in accordance to market demand is still limited. To overcome the lack of selected local chicken, the Faculty of Animal Science, IPB has been developing superior local chicken breed since 2012-2018 namely IPB-D1. The up-to-date Next Generation Sequencing technology through RNA Sequencing can identify candidate genes and potential SNPs quickly, thoroughly and comprehensively, as biomarkers for increasing both productivity (egg production, growth rate, and resistant to diseases) and meat quality (tenderness, flavor, meat fiber and fatty acid composition). During the last 6 years (2012-2018), several studies have been conducted on genes related to various trais: (1) disease resistance: toll receptor-4 (TLR4), mycovirus-1 (Mx-1), natural resistance associated macrophage-1 (NRAMP-1), inducible nitric oxide synthase (iNOS), transforming growth factor-β (TGF-β) genes; (2) meat production: growth hormone receptor (GH-r), growth hormone secretagogue receptor (GHSR) genes; (3) meat quality: calpastatine (CAST), calpain (CAPN) and myostatin (MSTN) genes; and (4) composition of fatty acids: stearyol CoA desaturase (SCD) and salute carrier (SLC) genes. Genetic quality of native and local chickens might be improved to increase their production and meat quality in order to build the Indonesian chicken industry.

A muscle-specific calpain, CAPN3, forms a homotrimer

Calpain-3 (CAPN3), a 94-kDa member of the calpain protease family, is abundant in skeletal muscle. Mutations in the CAPN3 gene cause limb girdle muscular dystrophy type 2A, indicating that CAPN3 plays important roles in muscle physiology. CAPN3 has several unique features. A crystallographic study revealed that its C-terminal penta–EF-hand domains form a homodimer, suggesting that CAPN3 functions as a homodimeric protease. To analyze complex formation of CAPN3 in a more convenient manner, we performed blue native polyacrylamide gel electrophoresis and found that the observed molecular weight of native CAPN3, as well as recombinant CAPN3, was larger than 240 kDa. Further analysis by cross-linking and sequential immunoprecipitation revealed that CAPN3 in fact forms a homotrimer. Trimer formation was abolished by the deletion of the PEF domain, but not the CAPN3-specific insertion sequences NS, IS1, and IS2. The PEF domain alone formed a homodimer, as reported, but addition of the adjacent CBSW domain to its N-terminus reinforced the trimer-forming property. Collectively, these results suggest that CAPN3 forms a homotrimer in which the PEF domain's dimer-forming ability is influenced by other domains.

The ERG1a potassium channel increases basal intracellular calcium concentration and calpain activity in skeletal muscle cells

BackgroundSkeletal muscle atrophy is the net loss of muscle mass that results from an imbalance in protein synthesis and protein degradation. It occurs in response to several stimuli including disease, injury, starvation, and normal aging. Currently, there is no truly effective pharmacological therapy for atrophy; therefore, exploration of the mechanisms contributing to atrophy is essential because it will eventually lead to discovery of an effective therapeutic target. The ether-a-go-go related gene (ERG1A) K+ channel has been shown to contribute to atrophy by upregulating ubiquitin proteasome proteolysis in cachectic and unweighted mice and has also been implicated in calcium modulation in cancer cells.MethodsWe transduced C2C12 myotubes with either a human ERG1A encoded adenovirus or an appropriate control virus. We used fura-2 calcium indicator to measure intracellular calcium concentration and Calpain-Glo assay kits (ProMega) to measure calpain activity. Quantitative PCR was used to monitor gene expression and immunoblot evaluated protein abundances in cell lysates. Data were analyzed using either a Student’s t test or two-way ANOVAs and SAS software as indicated.ResultsExpression of human ERG1A in C2C12 myotubes increased basal intracellular calcium concentration 51.7% (p < 0.0001; n = 177). Further, it increased the combined activity of the calcium-activated cysteine proteases, calpain 1 and 2, by 31.9% (p < 0.08; n = 24); these are known to contribute to degradation of myofilaments. The increased calcium levels are likely a contributor to the increased calpain activity; however, the change in calpain activity may also be attributable to increased calpain protein abundance and/or a decrease in levels of the native calpain inhibitor, calpastatin. To explore the enhanced calpain activity further, we evaluated expression of calpain and calpastatin genes and observed no significant differences. There was no change in calpain 1 protein abundance; however, calpain 2 protein abundance decreased 40.7% (p < 0.05; n = 6). These changes do not contribute to an increase in calpain activity; however, we detected a 31.7% decrease (p < 0.05; n = 6) in calpastatin which could contribute to enhanced calpain activity.ConclusionsHuman ERG1A expression increases both intracellular calcium concentration and combined calpain 1 and 2 activity. The increased calpain activity is likely a result of the increased calcium levels and decreased calpastatin abundance.

Single Nucleotide Polymorphism (SNP) 316 on Calpain Gene in Aceh Cattle

Genetic polymorphisms of μ-calpain, a calcium-dependent protease specifically expressed in muscle and related to meat tenderness, have been investigated in cattle worldwide, but not well documented in Indonesian beef cattle. This study was done to evaluate the frequency of SNP 316 in the μ-calpain gene in Aceh cattle, a local Indonesian beef cattle plays important role in the fulfillment of red meat for peoples in Aceh and its neighboring areas. For this purpose, genomic DNA was isolated from 29 sirloin meats samples collected from cull, female aceh cattle slaughtered at the Slaughter House of Banda Aceh. The cattle were purposively selected based on physical characteristics and hair colors referred to Indonesian law. For the SNP genotyping, PCR-RFLP methods were set up. The results showed all three genotypes namely CC, CG, and GG were found in Aceh cattle. The allele and genotype frequencies of SNP CAPN316 in the CAPN gene were: C – 0.14 and G – 0.86; CC – 3.4%, CG – 20.7% and GG – 75.9%. The observed and expected frequencies of CAPN SNP 316 in the cattle population examined were GG 22.0 and 21.6, CG 6.0 and 6.9, and CC 1.0 and 0.6.

Utilization of Molecular Marker to Improve Cattle Carcass Quality in Indonesia

Cattle is one of the commodities that have a national priority to achieve self-sufficiency in animal protein food for the Indonesian people. Beside beef sufficiency, demand on good quality meat in Indonesia is also increasing. Good quality carcass with lower fat content can give higher economic value. The purpose of this paper is to discuss the use of molecular markers to improve the quality of beef cattle carcass. Heritability value in carcass characteristic is low to moderate value, but it can be increased by selection using certain molecular markers. Several genes have been identified and correlated with carcass quality in several breed of cattle. Study in Bali cattle showed that the Calpain (CAPN1) and Calpastatin (CASTN) genes could be used as molecular markers to select Bali cattle with higher quality carcass because these genes were associated with carcass quality traits. In conclusion that Calpain (CAPN1) and Calpastatin (CASTN) genes can be used for local beef cattle selection toward better carcass quality and have opportunity to be utilized to improve carcass quality of other beef cattle breeds in Indonesia.

Gene Correction of LGMD2A Patient-Specific iPSCs for the Development of Targeted Autologous Cell Therapy.

Limb girdle muscular dystrophy type 2A (LGMD2A), caused by mutations in the Calpain 3 (CAPN3) gene, is an incurable autosomal recessive disorder that results in muscle wasting and loss of ambulation. To test the feasibility of an autologous induced pluripotent stem cell (iPSC)-based therapy for LGMD2A, here we applied CRISPR-Cas9-mediated genome editing to iPSCs from three LGMD2A patients to enable correction of mutations in the CAPN3 gene. Using a gene knockin approach, we genome edited iPSCs carrying three different CAPN3 mutations, and we demonstrated the rescue of CAPN3 protein in myotube derivatives invitro. Transplantation of gene-corrected LGMD2A myogenic progenitors in a novel mouse model combining immunodeficiency and a lack of CAPN3 resulted in muscle engraftment and rescue of the CAPN3 mRNA. Thus, we provide here proof of concept for the integration of genome editing and iPSC technologies to develop a novel autologous cell therapy for LGMD2A.

The Identification of Novel Single Nucleotide Polymorphisms in Calpain 1 (CAPN1) Gene of Japanese Quail (Coturnix coturnix japonica)

Objective: Calpains, in particular μ-calpain, are responsible for the post mortem proteolysis processes in muscle tissue and have main influences on meat quality. The CAPN1 gene that codes for large subunit of μ-calpain is revealed as a candidate gene related with meat quality and tenderization traits for livestock. For this reason, in this study it is aimed to investigate the genetic variation of CAPN1 gene in Japanese quails. Material and Methods: In this study, the genetic variation of CAPN1 gene was analyzed via DNA sequencing of 35 (13 males and 12 females) Japanese quails which were reared in Tekirdağ Namık Kemal University, Animal Research Unit. Results: Some genetic variants which are found in the 4th and 5th exons are as g.103969C&amp;gt;T in the 4th exon region and eight novel SNPs as g.104116A&amp;gt;T, g.104118T&amp;gt;G, g.104148G&amp;gt;C, g.104169G&amp;gt;C, g.104172A&amp;gt;G, g.104179C&amp;gt;G, g.104181G&amp;gt;A, g.104184T&amp;gt;C in the 5th exon of CAPN1 gene. The novel DNA polymorphisms of CAPN1 gene in Japanese quails are reported for the first time in this study and these sequences were deposited to NCBI GenBank Database, with the accession numbers MK496828-MK496837, respectively. g.103969C&amp;gt;T transversion which is localized in the 4th exon region and g.104148G&amp;gt;C, g.104169G&amp;gt;C transversions and g.104172A&amp;gt;G, g.104181G&amp;gt;A, g.104184T&amp;gt;C transitions which are localized in the 5th exon region have not caused an amino acid change. Instead, g.104116A&amp;gt;T, g.104118T&amp;gt;G tranversions caused the change from Threonine to Serine amino acid. Similarly, C→G transversion which was observed on the 104179th position caused the amino acid change from Proline to Alanine. Conclusion: These observed SNPs may have an effect on meat yield and tenderness in quails, so further researches are needed to demonstrate this hypothesis and these SNPs may be candidate SNPs for quails breeding.

PHLPP2 stabilization by p27 mediates its inhibition of bladder cancer invasion by promoting autophagic degradation of MMP2 protein

Pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2) is a tumor suppressor that catalyzes the de-phosphorylation of the AGC kinases, while p27 acts as a tumor suppressor that regulates cell cycle, apoptosis, and cell motility. Our previous studies have identified that PHLPP2 participates in inhibition of transformation of human bronchial epithelial cells following lung carcinogen B[a]P/B[a]PDE exposure. However, nothing was known about the association of p27 with regulation of PHLPP2 expression and the role of PHLPP2 in bladder cancer (BC) invasion. In our current studies, we demonstrated that PHLPP2 inhibited BC invasion through promoting MMP2 degradation via p62-mediated autophagy; and p27 expression was able to stabilize PHLPP2 protein by inhibiting protein degradation of Hsp90, which could directly bind to PHLPP2 and protect it from degradation. More in-depth studies discovered that stabilization of Hsp90 by p27 was mediated by calpain1 proteolysis system, whereas p27 inhibited calpain1 gene transcription by attenuating Jak1/Stat1 cascade in human invasive BC cells. Collectively, we for the first time revealed PHLPP2 downregulation in BCs and its participating in promotion of BC invasion, as well as novel role of p27 and mechanisms underlying its regulation of PHLPP2 protein degradation through Hsp90-dependent manner. Our findings improve our understanding of p27 and PHLPP2 roles and their crosstalk in regulation of BC invasion, which further contributes to improve the current strategy for invasive bladder cancer therapy.

CHARACTERISTICS OF UKRAINIAN GREY CATTLE BY DNA-MARKERS

CHARACTERISTICS OF UKRAINIAN GREY CATTLE BY DNA-MARKERS

MODERN MOLECULAR-GENETIC APPROACH TO INCREASE EFFICIENCY OF SELECTION PROCESS IN ANIMAL BREEDING OF UKRAINE

MODERN MOLECULAR-GENETIC APPROACH TO INCREASE EFFICIENCY OF SELECTION PROCESS IN ANIMAL BREEDING OF UKRAINE

CAPN3, DCT, MLANA and TYRP1 are overexpressed in skin of vitiligo vulgaris Mexican patients.

Vitiligo is a disorder causing skin depigmentation, in which several factors have been proposed for its pathogenesis: Environmental, genetic and biological aspects of melanocytes, even those of the surrounding keratinocytes. However, the lack of understanding of the mechanisms has complicated the task of predicting the development and progression. The present study used microarray analysis to characterize the transcriptional profile of skin from Vitiligo Vulgaris (VV) patients and the identified transcripts were validated using targeted high-throughput RNA sequencing in a broader set of patients. For microarrays, mRNA was taken from 20 skin biopsies of 10 patients with VV (pigmented and depigmented skin biopsy of each), and 5 biopsies of healthy subjects matched for age and sex were used as a control. A signature was identified that contains the expression pattern of 722 genes between depigmented vitiligo skin vs. healthy control, 1,108 between the pigmented skin of vitiligo vs. healthy controls and 1,927 between pigmented skin, depigmented vitiligo and healthy controls (P<0.05; false discovery rate, <0.1). When comparing the pigmented and depigmented skin of patients with vitiligo, which reflects the real difference between both skin types, 5 differentially expressed genes were identified and further validated in 45 additional VV patients by RNA sequencing. This analysis showed significantly higher RNA levels of calpain-3, dopachrome tautomerase, melan-A and tyrosinase-related protein-1 genes. The data revealed that the pigmented skin of vitiligo is already affected at the level of gene expression and that the main differences between pigmented and non-pigmented skin are explained by the expression of genes associated with pigment metabolism.