Differences In Skin Pigmentation Research Articles

Clinical photography processes (ClinPhoto) study for photo diversity

Although clinical photography serves an important role in the education of clinicians, there is still a disparity of darker skin tones in the photographs used for medical education. This disparity results in a skill deficit for clinicians because the differences in skin pigmentation change the appearance of visible diseases so that it is essential for students and trainees to have examples of clinical photographs on varying skin tones. To effectively address the problem, we need to understand the complex sociotechnical processes involved in clinical photography, which is more than simply the act of taking a photograph. Therefore, we conducted semi-structured interviews on clinical photography with 10 clinicians, 1 medical photographer, and 1 clinical administrator at a tertiary academic medical centre. The interviews revealed 5 deductive themes based on the questions and 19 inductive codes within those themes on how clinical photography is conducted. Analysis of the themes through a lens of critical theory showed how simple awareness of the disparity has not led to interventions for the poor representation of varying skin tones in photographs for medical education and also suggests initial next steps.

517 Racial differences in modified finnegan neonatal abstinence scoring for neonatal opioid withdrawal syndrome

Neonates exposed in-utero to opioids are commonly evaluated for neonatal opioid withdrawal syndrome (NOWS) using modified Finnegan Neonatal Abstinence Scoring System (FNASS). FNASS includes 21 different components of central nervous system, metabolic, vasomotor, respiratory, and GI disturbances. Consecutive cumulative scores ≥8 are suggestive for starting pharmacologic treatment. Our objective was to identify significant differences in FNASS scoring in neonates stratified by race. Retrospective cohort study of patients with opioid use disorder (OUD) who received co-located prenatal and addiction care from 2013 to 2020 at a large academic institution. Non-Hispanic Black (NHB) patients were matched to non-Hispanic White (NHW) patients by year and gestational age at delivery. Race and ethnicity were self-reported by the mother. The primary outcome was differences in individual scoring components. 42 NHB mother-newborn dyads were compared to 42 matched NWH dyads. There were no significant differences in baseline demographics between the groups. NHB newborns were significantly less likely than NHW to be scored for observed red, blotchy skin changes consistent with skin mottling (79% vs 100%, P<0.01). All NHB and NHW newborns were scored for mild tremors when disturbed and increased muscle tone; there were no significant scoring differences in the remaining FNASS components. NHB newborns were less likely to receive a FNASS ≥8 (69% vs. 81%, RR 0.85, CI 0.66-1.09) compared to NHW infants, and to receive pharmacological treatment for NOWS (76% vs. 98%, RR 0.78, CI 0.66-0.93) compared with NHW newborns. However, within this cohort of NHB newborns, receiving a score for mottling would have resulted in earlier and/or increased rates of pharmacologic treatment for NOWS in 36% (n=15) of patients. Infants born to NHB patients were less likely to receive score for skin mottling on modified FNASS. Lack of recognition of mottling maybe due to skin pigmentation differences and could potentially result in underscoring and delay of pharmacological treatment for NOWS.

Genetic ancestry, skin color and social attainment: The four cities study.

IntroductionThe Black population in the US is heterogeneous but is often treated as monolithic in research, with skin pigmentation being the primary indicator of racial classification. Objective: This paper examines the differences among Blacks by comparing genetic ancestry, skin color and social attainment of 259 residents across four US cities—Norman, Oklahoma; Cincinnati, Ohio; Harlem, New York; and Washington, District of Columbia.MethodsParticipants were recruited between 2004 and 2006 at community-based forums. Cross-sectional data were analyzed using chi-square tests, correlation analyses and logistic regression.ResultsThere were variations in ancestry, melanin index and social attainment across some cities. Overall, men with darker skin color, and women with lighter skin color were significantly more likely to be married. Darker skin individuals with significantly more West African ancestry reported attainment of graduate degrees, and professional occupations than lighter skin individuals.ConclusionsOur findings suggest differences in skin pigmentation by geography and support regional variations in ancestry of US Blacks. Biomedical research should consider genetic ancestry and local historical/social context rather than relying solely on skin pigmentation as a proxy for race.

Skin Pigmentation Differences between Mongolian, Korean, and Uzbekistan Ancient Human DNA Samples

Background This study reports the use of real-time PCR to identify the SNP rs1545397 in the intron region on the OCA2 gene from ancient and degraded DNA isolated from ancient human bones from Mongolia, Korea, and Uzbekistan. This SNP is a marker for skin pigmentation. LightCycler-based probes (HybProbes) were designed. A LightCycler (version 2.0) system was used for the real-time PCR. Results The results of the real-time PCRs of three different genotypes of SNP rs1545397 were compared with those of the direct sequencing. Melting curve analysis was used for genotype determination. Three genotypes were distinguished: the homozygous T (T/T) SNP type formed a distinct melting peak at 53.3 ± 0.14°C, the homozygous A (A/A) SNP type formed a distinct melting peak at 57.8 ± 0.12°C, and the heterozygous A/T SNP type formed two distinct melting peaks at 53.3 ± 0.17°C and 57.8 ± 0.15°C. Mongolian aDNA samples tested in this study carried all three types of the SNP (A/T, A/A, and T/T) with no distinctly predominant type observed. In contrast, Korean aDNA samples carried the Asian genotype (T/T), while the Uzbekistan aDNA samples carried the European genotype (A/A) more often than the Asian genotype (T/T). Conclusions Human Mongolian aDNA samples had A/T, A/A, and T/T SNP rs1545397 with no distinct predominant genotype. When combined with the archeological and aDNA studies of other coupling morphologies with aDNA, our results infer that Mongolia's prehistoric population had considerable heterogeneity of skin color and morphological traits and that in the Neolithic period, a Eurasian or mixed population inhabited the western part of Mongolia.

Association of Differing Qatari Genotypes with Vitamin D Metabolites.

Objective Genetic studies have identified four Qatari genotypes: Q1 Arab, Bedouin; Q2 Asian/Persian; Q3 African; and a fourth admixed group not fitting into the previous 3 groups. This study was undertaken to determine if there was an increased risk of deficiency of vitamin D and its metabolites associated with differing genotypes, perhaps due to genetic differences in skin pigmentation. Methods 398 Qatari subjects (220 type 2 diabetes and 178 controls) had their genotype determined by Affymetrix 500 k SNP arrays. Total values of 1,25-dihydroxyvitamin D (1,25(OH)2D), 25-hydroxyvitamin D (25(OH)D), 24,25-dihydroxyvitamin D (24,25(OH)2D), and 25-hydroxy-3epi-vitamin D (3epi-25(OH)D) concentrations were measured by the LC-MS/MS analysis. Results The distribution was as follows: 164 (41.2%) genotyped Q1, 149 (37.4%) genotyped Q2, 31 (7.8%) genotyped Q3, and 54 (13.6%) genotyped “admixed.” Median levels of 25(OH)D and 3epi-25(OH)D did not differ across Q1, Q2, Q3, and “admixed” genotypes, respectively. 1,25(OH)2D levels were lower (p < 0.04) between Q2 and the admixed groups, and 24,25(OH)2D levels were lower (p < 0.05) between Q1 and the admixed groups. Vitamin D metabolite levels were lower in females for 25(OH)D, 1,25(OH)2D (p < 0.001), and 24,25(OH)2D (p < 0.006), but 3epi-25(OH)D did not differ (p < 0.26). Diabetes prevalence was not different between genotypes. Total 1,25(OH)2D (p < 0.001), total 24,25(OH)2D (p < 0.001), and total 3epi-25(OH)D (p < 0.005) were all significantly lower in diabetes patients compared to controls whilst the total 25(OH)D was higher in diabetes than controls (p < 0.001). Conclusion Whilst 25(OH)D levels did not differ between genotype groups, 1,25(OH)2D and 24,25(OH)2D were lower in the admixed group, suggesting that there are genetic differences in vitamin D metabolism that may be of importance in a population that may allow a more targeted approach to vitamin D replacement. This may be of specific importance in vitamin D replacement strategies with the Q2 genotype requiring less, and the other genotypes requiring more to increase 1,25(OH)2D. Whilst overall the group was vitamin D deficient, total 25(OH)D was higher in diabetes, but 1,25(OH)2D, 24,25(OH)2D, and 3epi-25(OH)D were lower in diabetes that did not affect the relationship to genotype.

Anemia z niedoboru żelaza u dzieci – o czym warto pamiętać

Iron deficiency anemia is the most common cause of anemia in children. In Poland, anemia may occur in about 22% of children. Paleness of the skin is a rather uncertain symptom due to differences in skin pigmentation, mucosal color should be assessed by physical examination. The first laboratory check-up should be done around 6 months of age. Ferritin levels should always be evaluated with CRP because ferritin is an acute phase protein. The greatest need for iron in a child appears around 4-5 months of age. Causes of anemia that cannot be treated with iron: celiac disease, lambliosis, Crohn’s disease, lead poisoning, anemia of chronic diseases (initial stage), thalassemia. After starting iron treatment, you should always evaluate the effects after 4 weeks and deepen the diagnostics if necessary.

Low levels of vitamin D poorly responsive to daylight exposure in patients with therapy-resistant schizophrenia

Background: Low vitamin D levels are associated with schizophrenia, but the possible association between vitamin D levels and illness severity or duration of exposure to daylight has barely been investigated.Aims: To compare vitamin D levels in therapy-refractory severely ill schizophrenia patients and members of staff. To investigate the influence of daylight exposure on vitamin D levels in patients.Methods: Vitamin D was measured in patients with therapy-resistant schizophrenia in April, after the winter, and in patients and staff members in June, after an exceptionally sunny spring. Vitamin D levels in April and June were compared in patients, and levels in June were compared in patients and staff. The influence of daylight was taken into account by comparing the time patients spent outdoors during the day with the recommended minimum time for adequate vitamin D synthesis, and by comparing time spent outdoors in patients and staff.Results: Patients had high rates of vitamin D deficiency (79–90%) and lower levels of vitamin D than staff members (p < 0.001), independent of skin pigmentation. In patients, vitamin D levels did not normalize, despite the considerably longer than recommended exposure of the skin to daylight (p < 0.001) and the longer exposure in patients than in staff members (p = 0.003).Conclusion: The vitamin D deficiency of therapy-resistant schizophrenia patients is pronounced and cannot be explained by differences in skin pigmentation or by an inactive, indoor lifestyle on the ward. Even theoretically sufficient exposure of the patients to daylight did not ameliorate the low vitamin D levels.Clinical implications: While vitamin D deficiency probably plays a role in somatic health problems, it may also play a role in schizophrenia. Interestingly, exposure to daylight during an unusually sunny spring was not sufficient to correct the vitamin D deficiency seen in the patients. This emphasizes the need to measure and correct vitamin D levels in these patients.

Cardiac manifestations of Pallister–Killian syndrome

Pallister-Killian syndrome (PKS) is a sporadic multisystem genetic diagnosis characterized by facial dysmorphia, variable developmental delay and intellectual impairment, hypotonia, hearing loss, seizures, differences in skin pigmentation, temporal alopecia, diaphragmatic hernia, congenital heart defects, and other systemic abnormalities. Although congenital heart defects have been described in association with PKS, the full spectrum of heart disease is still not entirely known. Here, we describe the pattern of cardiac findings of 81 probands with PKS who have had at least one cardiac evaluation, demonstrating structural heart difference in 37% of our cohort (n = 30). Septal defects such as atrial or ventricular septal defects (n = 12) were the most commonly seen congenital heart differences. Additional findings included the occasional occurrence of bicuspid aortic valve, aortic dilatation, and cardiac hypertrophy/cardiomyopathy. We suggest cardiac evaluation for all individuals with PKS at the time of diagnosis as well as subsequent longitudinal follow-up to monitor for the development of cardiomyopathy and aortic dilatation.

Progressive Genetic Architecture of Human Skin Pigmentation

Skin pigmentation is an important human phenotypic trait whose regulation, in spite of recent advances, has not been fully understood. Global variation in skin pigmentation is one of the most striking examples of environmental adaptation in humans. From genome-wide association studies (GWAS), almost four hundreds loci have been identified as candidate genes in model organisms. Nevertheless, only few of them have been found to be significantly associated with human skin pigmentation differences in African, Asian, and European populations. Further, the evolutionary history of different pigmentation genes is rather complex: some loci have been subjected to strong positive selection, while others evolved under the relaxation of functional constraints in low ultraviolet (UV) environment.In this manuscript, we report the current genetic architecture implicated in human skin pigmentation. Eventually, we conclude that this complex trait is strived to a bright future.

Vitamin D and multiple sclerosis in Asians and Caucasians: environmental and genetic aspects

AbstractSeveral genetic and environmental factors are thought to be associated with an increased risk of multiple sclerosis (MS), the influence of which can differ between ethnicities. One of the most important risk factors for MS is low serum levels of vitamin D, and these levels also differ between ethnicities, probably mainly because of differences in skin pigmentation. Furthermore, genetic influences in vitamin D‐related genes might also vary between ethnicities, reflecting different genetic backgrounds. The present review article discusses the association between vitamin D and MS, with a focus on Asians and Caucasians.

Global Patterns of Diversity and Selection in Human Tyrosinase Gene

Global variation in skin pigmentation is one of the most striking examples of environmental adaptation in humans. More than two hundred loci have been identified as candidate genes in model organisms and a few tens of these have been found to be significantly associated with human skin pigmentation in genome-wide association studies. However, the evolutionary history of different pigmentation genes is rather complex: some loci have been subjected to strong positive selection, while others evolved under the relaxation of functional constraints in low UV environment. Here we report the results of a global study of the human tyrosinase gene, which is one of the key enzymes in melanin production, to assess the role of its variation in the evolution of skin pigmentation differences among human populations. We observe a higher rate of non-synonymous polymorphisms in the European sample consistent with the relaxation of selective constraints. A similar pattern was previously observed in the MC1R gene and concurs with UV radiation-driven model of skin color evolution by which mutations leading to lower melanin levels and decreased photoprotection are subject to purifying selection at low latitudes while being tolerated or even favored at higher latitudes because they facilitate UV-dependent vitamin D production. Our coalescent date estimates suggest that the non-synonymous variants, which are frequent in Europe and North Africa, are recent and have emerged after the separation of East and West Eurasian populations.

Is increased constitutive skin and hair pigmentation an early sign of puberty?

The paper analyzes data concerning the constitutive skin and hair pigmentation of 7–10-year-old Polish children to examine whether the hormonal activity of the gonads, which increases in this period, causes changes in pigmentation levels that may be considered an early sign of puberty. The study involved 289 children (151 girls and 138 boys). Skin pigmentation was examined on the medial side of the arm, while hair pigmentation on strands of hair close to the scalp in the occipital area. Additionally, body height (B-v) was measured and compared with population norms. On this basis, it was ascertained that the studied sample was representative of the population from which it was taken and that it represented the prepubertal and early pubertal stages of ontogeny (prior to the pubertal growth spurt or the first menstruation in the studied girls). It was found that in 7–10-year-old Polish children there is a statistically significant (p=0.001) increase in skin and hair pigmentation levels, while the degree of pigmentation of both structures at this stage of ontogeny is sexually dimorphic: girls are characterized by stronger pigmentation than boys. At the age of 10 years, the dimorphic differences in skin pigmentation intensify due to a rapid rise in pigmentation in girls. This change may be deemed an early morphological sign of puberty, as it precedes the pubertal growth spurt and menarche. This fast increase in skin pigmentation is not paralleled by an analogous change in hair pigmentation.

Total 25-OH Vitamin D Concentrations in Chinese, Malays and Indians

Total 25-OH Vitamin D Concentrations in Chinese, Malays and Indians

OPRM1 and EGFR contribute to skin pigmentation differences between Indigenous Americans and Europeans

Contemporary variation in skin pigmentation is the result of hundreds of thousands years of human evolution in new and changing environments. Previous studies have identified several genes involved in skin pigmentation differences among African, Asian, and European populations. However, none have examined skin pigmentation variation among Indigenous American populations, creating a critical gap in our understanding of skin pigmentation variation. This study investigates signatures of selection at 76 pigmentation candidate genes that may contribute to skin pigmentation differences between Indigenous Americans and Europeans. Analysis was performed on two samples of Indigenous Americans genotyped on genome-wide SNP arrays. Using four tests for natural selection--locus-specific branch length (LSBL), ratio of heterozygosities (lnRH), Tajima's D difference, and extended haplotype homozygosity (EHH)--we identified 14 selection-nominated candidate genes (SNCGs). SNPs in each of the SNCGs were tested for association with skin pigmentation in 515 admixed Indigenous American and European individuals from regions of the Americas with high ground-level ultraviolet radiation. In addition to SLC24A5 and SLC45A2, genes previously associated with European/non-European differences in skin pigmentation, OPRM1 and EGFR were associated with variation in skin pigmentation in New World populations for the first time.

Abstract B81: Vitamin D and prostate cancer aggressiveness among African and European Americans in the North Carolina-Louisiana Prostate Cancer Project (PCaP) case study cohort

Abstract 25(OH) vitamin D3 [25D3] serum levels have been associated with increased risk and unfavorable outcomes in several types of cancer, including breast, bladder, lung, and colon cancer. The relationship between vitamin D and prostate cancer prognosis and outcome is less well-studied. This pilot study utilized 200 samples from the North Carolina-Louisiana Prostate Cancer Project (PCaP) cohort to investigate the association between circulating 25D3 levels and an aggressive phenotype of prostate cancer in 100 African American (AA) and 100 European American (EA) men. Plasma vitamin D levels were categorized as deficient ≤20 ng/ml, insufficient ≤30 and &amp;gt;20 ng/ml, and sufficient &amp;gt;30ng/ml. The mean value of plasma vitamin D levels in the 200 research subjects was 24.7 ng/ml (STD 11.0, minimum value 6.3, and maximum value 62), which indicated vitamin D deficiency and insufficiency in a large portion of patients. AA men were more likely than EA men to present with vitamin D deficiency, which may be due to differences in skin pigmentation. As expected, significant (P &amp;lt;.0001) differences in vitamin D serum levels were found between AA men (mean value of 20.9 ng/ml) and EA men (mean value of 28.4 ng/ml). AA men with prostate cancer often present with vitamin D deficiency. Prostate tumor aggressiveness was categorized by PCaP as high, low, and intermediate, using clinical grade, clinical stage, and serum PSA at diagnosis [High aggressive: clinical stage ≥ T3 and Gleason grade ≥ 7 or Gleason sum ≥ 8 or PSA &amp;gt; 20; Low: Gleason sum &amp;lt; 7 and clinical stage ≤ T2 and PSA &amp;lt; 10]. An equal number of high aggressive (100 cases) and low aggressive (100 cases) tumors were included in the analysis. We then analyzed the relationship between vitamin D serum levels and prostate cancer aggressiveness. There was no significant correlation between disease aggressiveness and plasma concentrations of vitamin D. However, a significant inverse relationship was found between vitamin D and PSA levels (P=.0008). A trend was observed in which vitamin D deficient (&amp;lt;20ng/ml) AA men were diagnosed with more aggressive prostate cancer than AA men who were either vitamin D insufficient or sufficient. Specifically, out of 100 AA men with prostate cancer 59 were 25D3 deficient. Of these, over 50 percent had tumors classified as high aggressive. A similar trend was not observed among EA men. We controlled for season of blood collection: EA men had their lowest levels of circulating vitamin D during winter. Seasonal differences were not observed among AA men. This pilot study will be extended to the entire PCaP cohort of 2256 men in order to confirm these observations. In addition, we will continue to investigate the role of diet and dietary supplements on vitamin D levels in the PCaP cohort. Further analyses will add racial admixture estimates into our models in order to correct for population stratification. This is necessary since self-identified race may or may not reflect ancestral origins accurately. Acknowledgments: The authors thank the North Carolina Central Cancer Registry, the Louisiana Tumor Registry, and the PCaP staff, advisory committees and participants for their important contributions. The Prostate Cancer Project (PCaP) is carried out as a collaborative study supported by the Department of Defense contract DAMD 17-03-2-0052. AWR is supported by the Department of Defense grant W81WH11-1-0308 and R25CA113951-01 grant from the National Cancer Institute. Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):B81.

Identifying genes underlying skin pigmentation differences among human populations

Skin pigmentation is a human phenotype that varies greatly among human populations and it has long been speculated that this variation is adaptive. We therefore expect the genes that contribute to these large differences in phenotype to show large allele frequency differences among populations and to possibly harbor signatures of positive selection. To identify the loci that likely contribute to among-population human skin pigmentation differences, we measured allele frequency differentiation among Europeans, Chinese and Africans for 24 human pigmentation genes from 2 publicly available, large scale SNP data sets. Several skin pigmentation genes show unusually large allele frequency differences among these populations. To determine whether these allele frequency differences might be due to selection, we employed a within-population test based on long-range haplotype structure and identified several outliers that have not been previously identified as putatively adaptive. Most notably, we identify the DCT gene as a candidate for recent positive selection in the Chinese. Moreover, our analyses suggest that it is likely that different genes are responsible for the lighter skin pigmentation found in different non-African populations.

Comments on correlations of IQ with skin color and geographic–demographic variables

A large number of national and geographic population samples were used to test the hypothesis that the variation in mean values of skin color in the diverse populations are consistently correlated with the mean measured or estimated IQs of the various groups, as are some other physical variables, known as an ecological correlation. Straightforward statistical analyses clearly bear out the hypothesis, showing a significant positive ecological correlation between lightness of mean skin color and mean IQ across different populations. The main limitation of such a study design is that correlations obtained from this type of analysis are completely non-informative regarding any causal or functional connection between individual differences in skin pigmentation and and individual differences in IQ, nor are they informative regarding the causal basis of the correlation, e.g., simple genetic association due to cross-assortative mating for skin color and IQ versus a pleiotropic correlation in which both of the phenotypically distinct but correlated traits are manifested by one and the same gene.

Wound care for patients with darkly pigmented skin

This article examines the main skin or wound assessment parameters used for patients with darkly pigmented skin. Differences in skin pigmentation are discussed along with the challenges health professionals encounter in clinical practice and why linking theory to practice is vital.

Role and modulation of tyrosinase/tyrosinase related protein‐1 complex and PKC beta‐I in melanogenesis

Role and modulation of tyrosinase/tyrosinase related protein‐1 complex and PKC beta‐I in melanogenesis

Skin pigmentation, biogeographical ancestry and admixture mapping.

Ancestry informative markers (AIMs) are genetic loci showing alleles with large frequency differences between populations. AIMs can be used to estimate biogeographical ancestry at the level of the population, subgroup (e.g. cases and controls) and individual. Ancestry estimates at both the subgroup and individual level can be directly instructive regarding the genetics of the phenotypes that differ qualitatively or in frequency between populations. These estimates can provide a compelling foundation for the use of admixture mapping (AM) methods to identify the genes underlying these traits. We present details of a panel of 34 AIMs and demonstrate how such studies can proceed, by using skin pigmentation as a model phenotype. We have genotyped these markers in two population samples with primarily African ancestry, viz. African Americans from Washington D.C. and an African Caribbean sample from Britain, and in a sample of European Americans from Pennsylvania. In the two African population samples, we observed significant correlations between estimates of individual ancestry and skin pigmentation as measured by reflectometry (R(2)=0.21, P<0.0001 for the African-American sample and R(2)=0.16, P<0.0001 for the British African-Caribbean sample). These correlations confirm the validity of the ancestry estimates and also indicate the high level of population structure related to admixture, a level that characterizes these populations and that is detectable by using other tests to identify genetic structure. We have also applied two methods of admixture mapping to test for the effects of three candidate genes (TYR, OCA2, MC1R) on pigmentation. We show that TYR and OCA2 have measurable effects on skin pigmentation differences between the west African and west European parental populations. This work indicates that it is possible to estimate the individual ancestry of a person based on DNA analysis with a reasonable number of well-defined genetic markers. The implications and applications of ancestry estimates in biomedical research are discussed.