Cigarette Smoke-Induced Interleukin-1 Alpha May Be Involved in the Pathogenesis of Adult Acne

Background

Lipid peroxide (LPO) in comedones, which are produced as a result of sebum oxidation, might potentially induce interleukin-1α (IL-1α) and exacerbate comedogenesis and inflammatory changes in comedones.

Objective

To investigate the relationship of proinflammatory cytokines and LPO levels in the extracts of comedones with the acne of clinical difference between smokers and non-smokers, and with the severity and distribution of the acne lesions.

Methods

Twenty-two non-smoking and 21 smoking adult acne patients were evaluated by comedone extraction and measurement of proinflammatory cytokines and LPO levels. Acne severity and distribution of the lesions were also analyzed.

Results

Relative to the non-smoking group, smokers had significantly higher levels of IL-1α and LPO in comedones. Their levels showed a positive correlation. However, there were no statistically significant difference between the severity or distribution of the disease and the levels of LPO and IL-1α in comedones.

Conclusion

Smoking may be involved in the pathogenesis of adult acne by increasing the oxidative stress that results in subsequent accumulation of LPO in comedones.     

Efficacy and safety of silymarin containing antioxidant serum as an adjuvant treatment of mild-to-moderate acne vulgaris: A prospective,open-label pilot study

Background

Silymarin is the active component of milk thistle, which has antioxidant properties by scavenging free radicals and potential comedolytic properties.

Aims

This study aimed to assess the efficacy and safety of 0.5% silymarin-loaded antioxidant serum (SAS) used to treat mild-to-moderate acne.

Patients and Methods

A prospective, open-label pilot study was conducted. We enrolled 22 Korean acne patients who applied the 0.5% SAS on the whole face twice daily while continuing the current anti-acne medications. Grade of acne severity, individual lesion counts, sebum output levels, skin erythema, and melanin pigmentation were assessed.

Results

After a 4-week application, the modified Global Acne Grading Score (mGAGS), Global Evaluation Acne (GEA) scale, and the acne lesion counts were significantly decreased. Sebum secretion, skin pigmentation, and erythema were also reduced during the study period, yet only the melanin pigmentation index reached statistical significance. Subgroup analysis revealed that the patients who took the low-dose oral isotretinoin during the study period showed more noticeable improvements in skin sebum output and melanin pigmentation. Additionally, no adverse event was associated with using the 0.5% SAS.

Conclusion

The 0.5% silymarin-containing antioxidant formulation improved acne's clinical severity and related skin biophysical parameters.     

Therapeutic efficacy of metronidazole by needle-free jet injection combined with blue light therapy in Moderate-to-Severe facial acne vulgaris

Background

Acne vulgaris is one of the most common dermatological diseases. Some topical treatments for acne used in combination, such as blue light and topical antibiotics (such as metronidazole) by needle-free jet injection (NFJI), are becoming prevalent in clinical practice, but the efficacy remains uncertain.

Methods

In order to investigate the effect of blue light combined with metronidazole by NFJI in the treatment of acne, the 251 enrolled patients were randomly assigned into the blue light group, metronidazole (MNZ) group, and MNZ + blue light group, and then received 6-weeks' treatment. A variety of objective and subjective methods such as clinical pictures, skin barrier physiological parameters (including trans-epidermal water loss (TEWL), stratum corneum hydration, facail surface sebum, erythema and pigmentation), the Investigator Global Assessment score, acne lesion count assessment, Patients' Self-Assessment, and VAS score were used to evaluate the efficacy and side effects of the treatments.

Results

Compared to the baseline, the MNZ + blue light group showed significant improvement in acne lesion count reduction, TEWL, straum corneum hydration, facial surface sebum and erythema (p < 0.05). The MNZ + blue light group showed significant differences compared with the MNZ group and blue light group in terms of acne lesion count reduction and erythema (p < 0.05) Compared to the MNZ group, the MNZ + blue light group demonstrated significant improvement in TEWL and sebum (p < 0.05). While compared to the blue light group, the MNZ + blue light group showed significant improvement in hydration (p < 0.05). There was no statistically significant difference among the three groups in pigmentation (p > 0.05).

Conclusion

The combination of MNZ by NFJI and blue light has a synergistic effect and can relieve acne skin lesion within 6 weeks in the treatment of moderate and moderate–to–severe facial acne vulgaris, meanwhile, this method has a good safety.     

Efficacy of the continuous use of a lotion with carbon dioxide on male subjects with mild acne

Objective

Acne vulgaris is caused by dyslipidemia, dyskeratosis and/or abnormal bacterial growth. The obstruction of skin pores due to hyperkeratosis of the infundibulum contributes to the formation of comedones. Thus, normalizing keratinization of epidermal cells in skin pores might be useful to improve acne. Recently, it has been found that the transcutaneous application of carbon dioxide (CO₂) regulates imbalances of the desquamatory process. In this study, we evaluated the efficacy of a skin lotion containing CO₂ on mild acne.

Methods

Twenty-four healthy Japanese males (20–29 years old) with mild acne attended this evaluation. The subjects were divided into 2 groups, one group used a skin lotion containing CO₂ and the other group used a skin lotion without CO₂. Following facial washing, each subject topically applied the skin lotion with or without CO₂ twice a day for 4 weeks. Prior to the start of the evaluation (week 0) and following 2 and 4 weeks of treatment, acne symptoms were assessed by a dermatologist and by instrumental measurements.

Results

Topical application of the skin lotion with CO₂ for 4 weeks significantly improved acne symptoms, which was recognized by the subjects. However, treatment with the skin lotion without CO₂ did not improve acne symptoms. This improvement of acne symptoms by CO₂ was not accompanied by changes in sebum levels, skin surface pH, skin capacitance, or porphyrin levels.

Conclusion

The transcutaneous application of a lotion with CO₂ improves acne symptoms by normalizing keratinization without affecting skin surface conditions.     

Heat-treated Pediococcus acidilactici LM1013-mediated inhibition of biofilm formation by Cutibacterium acnes and its application in acne vulgaris: A single-arm clinical trial

Purpose

Acne vulgaris is a common skin disease accompanied by chronic inflammation in the pilosebaceous follicles, resulting from excessive Cutibacterium acnes. This study aimed to investigate the inhibition of biofilm formation by C. acnes ATCC 6919 using heat-treated Pediococcus acidilactici LM1013 (HT-LM1013), previously isolated from the Korean traditional fermented alcoholic beverage—makgeolli, and its application as a leave-on-type product for patients with acne vulgaris.

Methods

HT-LM1013 was prepared by Lactomason and homogenized using a high-pressure homogenizer. The minimum inhibitory concentration (MIC), tricarboxylic acid (TCA) cycle, and lipase activity were evaluated for C. acnes inhibition. Inhibition of biofilm formation was demonstrated using a crystal violet solution. Damaged C. acnes was observed using field-emission scanning electron microscopy (FE-SEM). Clinical trials were performed using a leave-on-type product containing HT-LM1013.

Results

HT-LM1013 inhibited the TCA cycle (36.80%) and lipase activity using palmitate (31.89%), stearate (36.91%), and oleate (30.86%) as substrates at 1 × MIC (p < 0.01). After treatment with HT-LM1013, concave and elongated shapes of C. acnes were observed by FE-SEM. In addition, HT-LM1013 inhibited biofilm formation by 71.75% at 1 × MIC (p < 0.001) and removed 73.35% of mature biofilms (p < 0.01). In the clinical trial, the leave-on-type product decreased the number of closed comedones from 14.04 to 10.22, open comedones from 7.22 to 4.39%, and sebum content to 76.23% at week 4 (p < 0.01). The satisfaction score of the participants was recorded 3.83 on a five-point scale.

Conclusion

HT-LM1013 is potent for the treatment of acne vulgaris.     

0.5% Liposome-encapsulated 5-aminolevulinic acid (ALA) photodynamic therapy for acne treatment

Abstract

Background: Photodynamic therapy using topical 5-aminolevulinic acid (ALA) has been successful in treating acne vulgaris, but sun avoidance for at least 48 hours after treatment is necessary due to the risk of post-treatment photosensitivity. Recently, a lower concentration of liposome-encapsulated 5-ALA was introduced to minimize this risk. Objectives: To evaluate the efficacy and safety of liposome-encapsulated 0.5% 5-ALA in the photodynamic therapy of inflammatory acne and its effects on sebum secretion in Asian skin. Methods: Thirteen Korean subjects with inflammatory acne were administered 0.5% ALA spray before photoradiation treatment. Photoradiation was performed at 3.5–6.0 J/cm² three times during each of two visits, performed 2 weeks apart. Improvement of acne was evaluated subjectively and objectively based on the Korean Acne Grading System. Sebum secretion was measured quantitatively at each visit. Results: The mean reduction in acne grade at the end of the treatment was 43.2%. Of the patients, 69.2% reported improvements in subjective skin oiliness, but fewer showed objective reductions in sebum secretion as determined by the Sebumeter^® SM10. No serious adverse events were observed. Conclusion: Photodynamic therapy using liposome-encapsulated 0.5% 5-ALA improved inflammatory acne with minimal side effects in Asians.     

The clinical features of late onset acne compared with early onset acne in women

Background Little is known about the clinical characteristics of acne based on the age of onset. Objectives The aim of this study was to investigate the clinical characteristics of patients according to the age of onset of acne and evaluate whether the findings were related to regional differences in the density of Propionibacterium acnes or the levels of sebum secretion. Methods A total of 89 women were recruited. The acne lesions were assessed by counting the lesions using standard digital photographs. Digital fluorescent photography for the evaluation of the density of P. acnes were taken and quantitative measurements of facial sebum secretion were performed. Results In women with acne, the age of onset was negatively correlated with the number of comedones and the proportion of comedones. By comparing the number of comedones and the proportion of comedones, onset of acne after 21 years of age was defined as late onset acne. In the patients with late onset acne, the number of comedones, the total number of acne lesions and the proportions of comedones were significantly less than in the patients with early onset acne. However, there were no significant differences in the fluorescence density of P. acnes or the level of sebum secretion between the two groups. Conclusions The results of this study, using objective evaluation tools, suggest that late onset acne has different clinical characteristics. Other possible factors might explain the clinical differences in late onset acne.     

The use of pyruvic acid in the treatment of acne

BACKGROUND: Acne is one of the most common dermatological diseases, affecting about 50% of adolescents. Different chemical peelings are used in local treatment, either alone or in association with other therapies. OBJECTIVE: To evaluate the efficacy and tolerability of chemical peeling with pyruvic acid for treatment of mild to moderate papulo-pustular acne. METHODS: We conducted an open-label study in which patients affected by mild to moderate papulo-pustular acne were treated with 40-50% pyruvic acid every 2 weeks for a total of 3-4 months. Forty patients (26 women and 14 men), ranging in age from 18 to 30 years, were enrolled in the study. Evaluations of sebum production and skin hydration were performed before and after treatment in 24 patients. RESULTS: Complete remission was observed in 16 patients (40%), partial remission was detected in 20 patients (50%), and no improvement was seen in four patients (10%). No side-effects were observed during or after treatment. Post-treatment evaluation of sebum production in 24 patients revealed a reduction in sebum levels in all patients. Post-treatment values of cutaneous hydration did not vary significantly from pretreatment values in the 24 patients evaluated. CONCLUSIONS: The results of our study indicate that peeling with pyruvic acid can be considered an effective, safe and well-tolerated procedure in the treatment of patients affected by mild to moderate papulo-pustular acne.     

Serum and salivary adipsin levels and its association with insulin resistance in acne vulgaris patients

Background

There is scarcity in literature about the reliability of salivary markers in acne vulgaris.

Aims

The aims were to evaluate the insulin resistance (IR) and adipsin levels in serum and saliva in a sample of acne vulgaris patients; and to correlate IR and adipsin levels with the disease severity.

Methods

This prospective case–control study included 60 acne vulgaris patients (patients Group), in addition, 60 apparently healthy individuals (control group). The severity of acne vulgaris was determined according to Global Acne Grading system (GAGS). Serum and salivary adipsin, fasting glucose, and fasting insulin levels were measured using ELISA kits.

Results

Fasting glucose, fasting insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) in patients group both in serum and saliva were elevated when compared with the control group. Serum and salivary levels of adipsin and Quantitative insulin sensitivity check index (QUIKI) in patients were decreased than the control group. Adipsin serum levels show significant negative correlations with all study variables except QUIKI with which the correlation was positive both in serum and saliva. There was a significant positive correlation between serum and salivary adipsin levels (r = 0.873, p < 0.00001) and serum and salivary fasting glucose (r = 1, p < 0.00001).

Conclusion

Adipsin could be considered as a promising biomarker for acne vulgaris and its associated insulin resistance. Moreover, the salivary measurements may be considered as useful biomarkers in acne vulgaris patients, but more studies are still required.     

Acne Vulgaris and Quality of Life Among Young Adults in South India

Acne vulgaris is a chronic condition affecting more than 85% of adolescents and young adults. It is one of the most common diseases affecting humanity and its impact on quality of life (QoL) is important. The impact of acne on QoL in Indian patients remains undocumented. The study was undertaken to detect the impact of acne vulgaris and related factors that may influence the QoL.

Materials and Methods:

This was a hospital-based, prospective, cross-sectional, prestructured, questionnaire-based study done on 140 consenting individuals, who attended the Dermatology outpatient department. Acne vulgaris was graded using simple grading system. QoL was measured using a combination of skin disease-specific (Dermatological Life Quality Index (DLQI)) and acne-specific (Cardiff Acne Disability Index (CADI)) questionnaires.

Results:

Majority of our study population were students (103, 73.6%). Face (139, 99.3%) was the commonest site of acne and comedones 133, 95% were the commonest type of lesion. Most of the individuals 66, 47.1% were observed to have grade 1 acne. The mean DLQI score was 6.91 and the mean CADI score was 5.2. Association between the scores was statistically significant. Age, occupation, marital status, family, and treatment history played a role in affecting the QoL. Diet, smoking, and alcohol did not influence the QoL.

Conclusion:

Though acne had impact on patient''s QoL, it was less severe in our study. It is important for health professionals to incorporate QoL measurements when managing acne patients to provide better and appropriate care.     

Fluorescence diagnostic imaging in patients with acne

Background: Orange‐red fluorescence in the follicle openings, induced by ultraviolet A light, originates from porphyrins, the metabolic products of Propionibacteria acnes. Purpose: To investigate the relationship of orange‐red follicular fluorescence with the severity of acne and the amount of sebum secretion. Methods: Twenty‐five volunteers were included. The severity of acne was rated on a 4‐point scale. The casual sebum level was measured using a Sebumeter and the follicular fluorescence was determined using the camera Visiopor. Results: Casual sebum level and the intensity of fluorescence (percentage of the area and number of orange‐red spots) were higher at the T zone than at the U zone in all patients regardless of their skin type. Sebum amount and area of fluorescence spots were significantly negative in correlation with the clinical grade of acne. There was a significant positive correlation between the orange‐red fluorescence and the casual sebum level. Conclusion: The orange‐red fluorescence showed stronger correlation with the presence of non‐inflammatory acne lesions (comedones) and high sebum amount than the presence of inflammatory acne lesions (pustules) and low sebum amount. The fluorescence diagnostic imaging could be useful in the objective evaluation and monitoring of treatment efficacy in subjects with acne‐prone skin and patients with acne.     

Clinical comparison of salicylic acid peel and LED-Laser phototherapy for the treatment of Acne vulgaris in teenagers

Acne vulgaris treatments usually cause sensitivity, teratogenicity and bacterial resistance. Investigations of other therapeutic techniques, such as phototherapy, are highly relevant. Thus, we compared the effectiveness of two Acne vulgaris treatments in adolescents: peeling with salicylic acid (SA) and phototherapy. Teens were randomly divided into: group I, treatment with SA peels (10%) and group II, treatment with phototherapy (blue LED and red laser lights). Photographs were taken before and after ten sessions of each treatment, carried out weekly, and compared. To compare the differences between the treatments, the Student t-test was used. P values < 0.05 were considered significant. Both techniques are effective therapies for the treatment of acne in teenagers since the number of comedones, papules and pustules decreased significantly at the end of the session. However, when the two treatments were compared, phototherapy showed a significant difference in reducing the number of pustules. The combined use of red and blue lights due to their anti-inflammatory and wound-healing properties is a more efficient alternative for treating Acne vulgaris in relation to SA and proves more reliable and without side effects, improving the adolescents’ skin health.     

Acne analysis,grading and computational assessment methods: an overview

Introduction: This paper presents a comprehensive review of acne grading and measurement. Acne is a chronic disorder of the pilosebaceous units, with excess sebum production, follicular epidermal hyperproliferation, inflammation and Propionibacterium acnes activity. Most patients are affected with acne vulgaris, which is the prevalent type of acne. Acne vulgaris consists of comedones (whitehead and blackhead), papules, pustules, nodules and cysts. Objectives: To review and identify the issues for acne vulgaris grading and computational assessment methods. To determine the future direction for addressing the identified issues. Methods: There are two main methods of assessment for acne severity grading, namely, lesion counting and comparison of patient with a photographic standard. For the computational assessment method, the emphasis is on computational imaging techniques. Results: Current acne grading methods are very time consuming and tedious. Generally, they rely on approximation for counting lesions and hence the assessment is quite subjective, with both inter and intra‐observer variability. It is important to accurately assess acne grade to evaluate its severity as this influences treatment selection and assessment of response to therapy. This will further help in better disease management and more efficacious treatment. Conclusion: Semi‐automated or automated methods based on computational imaging techniques should be devised for acne grade assessment.     

Comparison of the epidemiology of acne vulgaris among Caucasian,Asian, Continental Indian and African American women

Background Acne vulgaris is a common skin disease with a large quality of life impact, characterized by comedones, inflammatory lesions, secondary dyspigmentation and scarring. There are few large objective studies comparing acne epidemiology between racial and ethnic groups. Objective This study aimed to define the prevalence and subtypes of acne in women of different racial groups from four ethnicities. Methods The sample consisted of 2895 (384 African American, 520 Asian, 1295 Caucasian, 258 Hispanic and 438 Continental Indian) women ranging in age from 10 to 70 years. Photographs of subjects were graded for acne lesions, scars, dyspigmentation, and measurements taken of sebum excretion and pore size. Results Clinical acne was more prevalent in African American and Hispanic women (37%, 32% respectively) than in Continental Indian, Caucasian and Asian (23%, 24%, 30% respectively) women. All racial groups displayed equal prevalence of both subtypes of acne with the exception of Asians, for whom inflammatory acne was more prevalent than comedonal (20% vs. 10%) acne, and in Caucasians, for whom comedonal acne was more prevalent than inflammatory (14% vs. 10%) acne. Hyperpigmentation was more prevalent in African American and Hispanic (65%, 48% respectively) than in Asian, Continental Indian and Caucasian (18%, 10%, 25% respectively) women. Dyspigmentation and atrophic scarring were more common in African American and Hispanic women than in all other ethnicities. There was a negative correlation between pore size and skin lightness for all ethnicities. Sebum production was positively correlated with acne severity in African American, Asian and Hispanic women, and pore size was positively correlated with acne in African American, Asian and Continental Indian women, (for all above results, P < 0.05). Limitations Only female participants were recruited. Data collection was restricted to four cities, with some ethnicities from single cities. Acne was evaluated only on the left side of the face and the two‐dimensional nature of photography may not capture all skin surface changes. Conclusion Acne prevalence and sequelae were more common in those with darker skin types, suggesting that acne is a more heterogeneous condition than previously described and highlight the importance of skin‐colour tailored treatment.     

Evaluation of 25‐hydroxy vitamin D levels and disease severity in patients with acne vulgaris

Acne vulgaris is a multifactorial skin disorder. Many etiological factors are speculated to contribute to the pathogenesis of acne, one of these is vitamin D deficiency. Previous studies reported contradictory results about serum 25 hydroxy vitamin D (25‐OH vitamin D) levels, its association with acne, some claimed that acne lesion might improve with vitamin D supplementation. We aimed to assess serum 25‐OH vitamin D levels in acne patients, identify their relation with disease severity in a larger study group. The study included 134 acne patients, 129 controls. Acne disease severity was identified with Global Acne Grading Scale (GAGS) scores. Serum 25‐OH vitamin D levels were measured in all groups. Serum 25‐OH vitamin D levels were significantly lower in acne patients than in controls (P < .001). The prevalence of vitamin D deficiency was significantly higher in acne group than in control group (77.6% vs 63.9%; P = .041). There was a negative‐strong statistically significant correlation detected between serum 25‐OH vitamin D levels and GAGS scores in patient group (P < .001; r = −.910). According to these results, we claim that evaluating serum 25‐OH vitamin D levels in acne patients, vitamin D supplementation as a treatment option may be a consideration for further studies.     

Acne vulgaris and the most popular and new cosmetological treatments

Introduction

Acne vulgaris is a disease that has an enormous impact on appearance of the skin of the patients and also on their quality of life. Long-term dermatological treatment, which often lasts years, and disease relapses contribute to the occurrence of low self-esteem and depression. Acne is one of the 10 most common diseases in the world and the most common inflammatory skin disease. Many methods of dermatological treatment that bring very good results are available. However, educating people with acne on how to take care of their skin on a daily basis to minimize the bleak effects of the disease is an extremely important element. Contemporary cosmetology creates an environment for not only taking care of the skin at home, but also develops in-office treatments with exfoliation of the dead epidermis as an extremely important and priority part of treatment. The cosmetologist can propose both chemical and apparatus methods, which are selected individually for each client.

Objective

The objective of this article is to provide information about cosmetological treatment used in acne vulgaris.

Methods

In this article, we reviewed the published literature, article published in peer-reviewed journals.

Results

There are many methods that work well in the case of acne skin care, more and more new treatments appear on the cosmetological market.

Conclusion

Acne skin care in beauty parlor is very important element.     

Treatment of mild to severe acne with 1726 nm laser: A safe alternative to traditional acne therapies

Introduction

Acne is the most common reason for dermatology consultation in adolescents and young adults. Consultation is often delayed despite unsuccessful self-treatment. Postponing effective treatment places acne sufferers at higher risk for permanent acne scars and post-inflammatory pigment changes.

Aim

This review discusses clinical challenges with present therapeutic options for acne treatment and the role of a 1726 nm laser for acne.

Methods

Current acne treatment guidelines were reviewed. A literature review was conducted for trials of light-based acne therapy. The selectivity of previous light-based therapies was reviewed.

Results

Available acne therapy is effective, but treatment-related side effects are common. Acne treatment guidelines do not include recommendations for light-based treatments. Different types of light-based treatments have been tried but until now no wavelength specifically targeted sebaceous glands.

Conclusion

The 1726 nm laser is safe and effective for treating mild to severe acne in all Fitzpatrick skin types. Acne resolution is apparent within the first month and improves for up to 2 years beyond treatment.     

The Difference in Sebum Secretion Affecting Development of Acne

BackgroundAlthough sebum secretion is crucial for acne development, acne lesion distribution is not always similar to the topographic differences of sebum secretion.ObjectiveTo analyze whether sebum secretion affects acne development and distribution and to assess other factors possibly influencing the relationship between acne and sebum secretion.MethodsThis single-center retrospective study included 67 acne patients and 50 controls. Acne patients were divided into 3 groups based on acne lesion distribution: T-zone dominant, U-zone dominant, and mixed groups. The secreted sebum level in each zone of acne patients was compared with that of controls. We also conducted correlation analysis between secreted sebum level and acne number, depending on the facial zone.ResultsNo significant difference was found between acne patients and controls regarding age and sex ratio. The U-zone dominant group showed increased sebum levels compared with controls in the U-zone and whole face, but a similar result was not obtained in the T-zone dominant group. Moreover, there was a significant correlation between the number of lesions and secreted sebum level in the U-zone, but not in the T-zone. Further, there was a more significant relation in the U-zone of male and young patients.ConclusionWe found that increased sebum secretion compared with the condition may affect acne development, especially in the U-zone. Sex and age may also influence the relationship between acne and increased sebum secretion. Acne lesion distribution may vary from patient to patient because sebum secretion affects acne differently depending on multiple factors.     

Acne in infancy and acne genetics

Acne is a disease that can be seen in the first year of age, early childhood, prepubertal age and puberty. Neonatal acne is due mainly to considerable sebum excretion rate, and infantile acne because of high androgens of adrenal origin in girls and of adrenal and testes in boys. These pathogenic mechanisms are characteristic in these ages. Important factors like early onset of comedones and high serum levels of dehydroepiandrosterone sulfate are predictors of severe or long-standing acne in prepubertal age. Hereditary factors play an important role in acne. Neonatal, nodulocystic acne and conglobate acne has proven genetic influences. Postadolescent acne is related with a first-degree relative with the condition in 50% of the cases. Chromosomal abnormalities, HLA phenotypes, polymorphism of human cytochrome P-450 1A1 and MUC1 gene are involved in the pathogenesis of acne. Several other genes are being studied.